We were used to assert it to be true but, given the value is not used in any shape, we can relax the definition and simply assert on the presence of the key. Closes #15251.
2721 lines
79 KiB
Elixir
2721 lines
79 KiB
Elixir
# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: 2021 The Elixir Team
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# SPDX-FileCopyrightText: 2012 Plataformatec
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defmodule Exception do
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@moduledoc """
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Functions for dealing with throw/catch/exit and exceptions.
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This module also defines the behaviour required by custom
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exceptions. To define your own, see `defexception/1`.
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## Formatting functions
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Several functions in this module help format exceptions.
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Some of these functions expect the stacktrace as argument.
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The stacktrace is typically available inside catch and
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rescue by using the `__STACKTRACE__/0` variable.
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Do not rely on the particular format returned by the
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functions in this module. They may be changed in future releases
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in order to better suit Elixir's tool chain. In other words,
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by using the functions in this module it is guaranteed you will
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format exceptions as in the current Elixir version being used.
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"""
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@typedoc "The exception type"
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@type t :: %{
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required(:__struct__) => module,
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required(:__exception__) => term,
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optional(atom) => any
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}
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@typedoc "The kind handled by formatting functions"
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@type kind :: :error | non_error_kind
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@type non_error_kind :: :exit | :throw | {:EXIT, pid}
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@type stacktrace :: [stacktrace_entry]
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@type stacktrace_entry ::
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{module, atom, arity_or_args, location}
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| {(... -> any), arity_or_args, location}
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@type arity_or_args :: non_neg_integer | list
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@type location :: keyword
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@doc """
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Receives the arguments given to `raise/2` and returns the exception struct.
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The default implementation accepts either a set of keyword arguments
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that is merged into the struct or a string to be used as the exception's message.
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"""
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@callback exception(term) :: t
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@doc """
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Receives the exception struct and must return its message.
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Many exceptions have a message field which by default is accessed
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by this function. However, if an exception does not have a message field,
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this function must be explicitly implemented.
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"""
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@callback message(t) :: String.t()
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@doc """
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Called from `Exception.blame/3` to augment the exception struct.
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Can be used to collect additional information about the exception
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or do some additional expensive computation.
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"""
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@callback blame(t, stacktrace) :: {t, stacktrace}
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@optional_callbacks [blame: 2]
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@doc false
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# Callback for formatting Erlang exceptions
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def format_error(%struct{} = exception, _stacktrace) do
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%{general: message(exception), reason: "#" <> Atom.to_string(struct)}
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end
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@doc false
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@deprecated "Use Kernel.is_exception/1 instead"
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def exception?(term)
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def exception?(%_{__exception__: _}), do: true
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def exception?(_), do: false
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@doc """
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Gets the message for an `exception`.
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This function will invoke the `c:message/1` callback on the exception
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module to retrieve the message. If the callback raises an exception or
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returns a non-binary value, this function will rescue the error and
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return a descriptive error message instead.
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"""
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@spec message(t) :: String.t()
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def message(%module{__exception__: _} = exception) do
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try do
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module.message(exception)
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rescue
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caught_exception ->
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"got #{inspect(caught_exception.__struct__)} with message " <>
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"#{inspect(message(caught_exception))} while retrieving Exception.message/1 " <>
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"for #{inspect(exception)}. Stacktrace:\n#{format_stacktrace(__STACKTRACE__)}"
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else
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result when is_binary(result) ->
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result
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result ->
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"got #{inspect(result)} " <>
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"while retrieving Exception.message/1 for #{inspect(exception)} " <>
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"(expected a string)"
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end
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end
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@doc """
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Normalizes an exception, converting Erlang exceptions
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to Elixir exceptions.
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It takes the `kind` spilled by `catch` as an argument and
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normalizes only `:error`, returning the untouched payload
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for others.
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The third argument is the stacktrace which is used to enrich
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a normalized error with more information. It is only used when
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the kind is an error.
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"""
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@spec normalize(:error, any, stacktrace) :: t
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@spec normalize(non_error_kind, payload, stacktrace) :: payload when payload: var
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def normalize(kind, payload, stacktrace \\ [])
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def normalize(:error, %_{__exception__: _} = payload, _stacktrace), do: payload
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def normalize(:error, payload, stacktrace), do: ErlangError.normalize(payload, stacktrace)
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def normalize(_kind, payload, _stacktrace), do: payload
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@doc """
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Normalizes and formats any throw/error/exit.
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The message is formatted and displayed in the same
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format as used by Elixir's CLI.
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The third argument is the stacktrace which is used to enrich
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a normalized error with more information. It is only used when
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the kind is an error.
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"""
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@spec format_banner(kind, any, stacktrace) :: String.t()
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def format_banner(kind, exception, stacktrace \\ [])
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def format_banner(:error, exception, stacktrace) do
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exception = normalize(:error, exception, stacktrace)
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"** (" <> inspect(exception.__struct__) <> ") " <> message(exception)
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end
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def format_banner(:throw, reason, _stacktrace) do
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"** (throw) " <> inspect(reason)
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end
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def format_banner(:exit, reason, _stacktrace) do
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"** (exit) " <> format_exit(reason, <<"\n ">>)
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end
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def format_banner({:EXIT, pid}, reason, _stacktrace) do
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"** (EXIT from #{inspect(pid)}) " <> format_exit(reason, <<"\n ">>)
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end
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@doc """
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Normalizes and formats throws/errors/exits and stacktraces.
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It relies on `format_banner/3` and `format_stacktrace/1`
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to generate the final format.
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If `kind` is `{:EXIT, pid}`, it does not generate a stacktrace,
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as such exits are retrieved as messages without stacktraces.
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"""
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@spec format(kind, any, stacktrace) :: String.t()
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def format(kind, payload, stacktrace \\ [])
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def format({:EXIT, _} = kind, any, _) do
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format_banner(kind, any)
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end
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def format(kind, payload, stacktrace) do
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message = format_banner(kind, payload, stacktrace)
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case stacktrace do
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[] -> message
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_ -> message <> "\n" <> format_stacktrace(stacktrace)
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end
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end
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@doc false
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def __format_message_with_term__(message, term) do
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inspected =
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term
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|> inspect(pretty: true)
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|> String.split("\n")
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|> Enum.map_intersperse("\n", fn
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"" -> ""
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line -> " " <> line
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end)
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IO.iodata_to_binary([message, "\n\n", inspected, "\n"])
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end
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@doc """
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Attaches information to throws/errors/exits for extra debugging.
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This operation is potentially expensive, as it reads data
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from the file system, parses beam files, evaluates code and
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so on.
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If `kind` argument is `:error` and the `error` is an Erlang exception, this function will
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normalize it. If the `error` argument is an Elixir exception, this function will invoke
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the optional `c:blame/2` callback on the exception module if it is implemented.
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Unlike `message/1`, this function will not rescue errors - if the callback raises an exception,
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the error will propagate to the caller. It is your choice if you want to rescue and return
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the original exception, return a different exception, or let it cascade.
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"""
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@doc since: "1.5.0"
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@spec blame(:error, any, stacktrace) :: {t, stacktrace}
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@spec blame(non_error_kind, payload, stacktrace) :: {payload, stacktrace} when payload: var
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def blame(kind, error, stacktrace)
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def blame(:error, error, stacktrace) do
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%module{} = struct = normalize(:error, error, stacktrace)
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if Code.ensure_loaded?(module) and function_exported?(module, :blame, 2) do
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module.blame(struct, stacktrace)
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else
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{struct, stacktrace}
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end
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end
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def blame(_kind, reason, stacktrace) do
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{reason, stacktrace}
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end
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@doc """
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Blames the invocation of the given module, function and arguments.
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This function will retrieve the available clauses from bytecode
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and evaluate them against the given arguments. The clauses are
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returned as a list of `{args, guards}` pairs where each argument
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and each top-level condition in a guard separated by `and`/`or`
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is wrapped in a tuple with blame metadata.
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This function returns either `{:ok, definition, clauses}` or `:error`.
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Where `definition` is `:def`, `:defp`, `:defmacro` or `:defmacrop`.
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"""
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@doc since: "1.5.0"
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@spec blame_mfa(module, function :: atom, args :: [term]) ::
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{:ok, :def | :defp | :defmacro | :defmacrop, [{args :: [term], guards :: [term]}]}
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| :error
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def blame_mfa(module, function, args)
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when is_atom(module) and is_atom(function) and is_list(args) do
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try do
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blame_mfa(module, function, length(args), args)
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rescue
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_ -> :error
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end
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end
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defp blame_mfa(module, function, arity, call_args) do
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with [_ | _] = path <- :code.which(module),
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{:ok, {_, [debug_info: debug_info]}} <- :beam_lib.chunks(path, [:debug_info]),
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{:debug_info_v1, backend, data} <- debug_info,
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{:ok, %{definitions: defs}} <- backend.debug_info(:elixir_v1, module, data, []),
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{_, kind, _, clauses} <- List.keyfind(defs, {function, arity}, 0) do
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clauses =
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for {meta, ex_args, guards, _block} <- clauses do
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scope = :elixir_erl.scope(meta, true)
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ann = :elixir_erl.get_ann(meta)
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{erl_args, scope} =
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:elixir_erl_clauses.match(ann, &:elixir_erl_pass.translate_args/3, ex_args, scope)
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{args, binding} =
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[call_args, ex_args, erl_args]
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|> Enum.zip()
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|> Enum.map_reduce([], &blame_arg/2)
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guards =
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guards
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|> Enum.map(&blame_guard(&1, ann, scope, binding))
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|> Enum.map(&Macro.prewalk(&1, fn guard -> translate_guard(guard) end))
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{args, guards}
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end
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{:ok, kind, clauses}
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else
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_ -> :error
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end
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end
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defp map_node?({:is_map, _, [_]}), do: true
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defp map_node?(_), do: false
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defp map_key_node?({:is_map_key, _, [_, _]}), do: true
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defp map_key_node?(_), do: false
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defp struct_validation_node?(
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{:is_atom, _, [{{:., [], [:erlang, :map_get]}, _, [:__struct__, _]}]}
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),
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do: true
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|
defp struct_validation_node?(
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{:==, _, [{{:., [], [:erlang, :map_get]}, _, [:__struct__, _]}, _module]}
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),
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do: true
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defp struct_validation_node?(_), do: false
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defp struct_macro?(
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{:and, _,
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[
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{:and, _, [%{node: node_1 = {_, _, [arg]}}, %{node: node_2 = {_, _, [arg, _]}}]},
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%{node: node_3 = {_, _, [{_, _, [_, arg]}]}}
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]}
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),
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do: map_node?(node_1) and map_key_node?(node_2) and struct_validation_node?(node_3)
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|
defp struct_macro?(
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{:and, _,
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[
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{:and, _,
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[
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{:and, _,
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[
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%{node: node_1 = {_, _, [arg]}},
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{:or, _, [%{node: {:is_atom, _, [_]}}, %{node: :fail}]}
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]},
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%{node: node_2 = {_, _, [arg, _]}}
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|
]},
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%{node: node_3 = {_, _, [{_, _, [_, arg]}, _]}}
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]}
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),
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|
do: map_node?(node_1) and map_key_node?(node_2) and struct_validation_node?(node_3)
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defp struct_macro?(_), do: false
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|
defp translate_guard(guard) do
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if struct_macro?(guard) do
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undo_is_struct_guard(guard)
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else
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guard
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end
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end
|
|
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defp undo_is_struct_guard({:and, meta, [_, %{node: {_, _, [{_, _, [_, arg]} | optional]}}]}) do
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|
args =
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case optional do
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[] -> [arg]
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|
[module] -> [arg, module]
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|
end
|
|
|
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%{match?: meta[:value], node: {:is_struct, meta, args}}
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end
|
|
|
|
defp blame_arg({call_arg, ex_arg, erl_arg}, binding) do
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|
{match?, binding} = blame_arg(erl_arg, call_arg, binding)
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{blame_wrap(match?, rewrite_arg(ex_arg)), binding}
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end
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|
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|
defp blame_arg(erl_arg, call_arg, binding) do
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|
binding = :orddict.store(:VAR, call_arg, binding)
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|
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|
try do
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|
ann = :erl_anno.new(0)
|
|
|
|
{:value, _, binding} =
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:erl_eval.expr({:match, ann, erl_arg, {:var, ann, :VAR}}, binding, :none)
|
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{true, binding}
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rescue
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_ -> {false, binding}
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end
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end
|
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defp rewrite_arg(arg) do
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Macro.prewalk(arg, fn
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{:%{}, meta, [__struct__: Range, first: first, last: last, step: step]} ->
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{:..//, meta, [first, last, step]}
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|
|
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other ->
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other
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end)
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end
|
|
|
|
defp blame_guard({{:., _, [:erlang, op]}, meta, [left, right]}, ann, scope, binding)
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|
when op == :andalso or op == :orelse do
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guards = [
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blame_guard(left, ann, scope, binding),
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blame_guard(right, ann, scope, binding)
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|
]
|
|
|
|
kernel_op =
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|
case op do
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:orelse -> :or
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|
:andalso -> :and
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|
end
|
|
|
|
evaluate_guard(kernel_op, meta, guards)
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end
|
|
|
|
defp blame_guard(ex_guard, ann, scope, binding) do
|
|
ex_guard
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|
|> blame_guard?(binding, ann, scope)
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|> blame_wrap(rewrite_guard(ex_guard))
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|
end
|
|
|
|
defp blame_guard?(ex_guard, binding, ann, scope) do
|
|
{erl_guard, _} = :elixir_erl_pass.translate(ex_guard, ann, scope)
|
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{:value, true, _} = :erl_eval.expr(erl_guard, binding, :none)
|
|
true
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|
rescue
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|
_ -> false
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|
end
|
|
|
|
defp evaluate_guard(kernel_op, meta, guards = [_, _]) do
|
|
[x, y] = Enum.map(guards, &evaluate_guard/1)
|
|
|
|
logic_value =
|
|
case kernel_op do
|
|
:or -> x or y
|
|
:and -> x and y
|
|
end
|
|
|
|
{kernel_op, Keyword.put(meta, :value, logic_value), guards}
|
|
end
|
|
|
|
defp evaluate_guard(%{match?: value}), do: value
|
|
defp evaluate_guard({_, meta, _}) when is_list(meta), do: meta[:value]
|
|
|
|
defp rewrite_guard(guard) do
|
|
Macro.prewalk(guard, fn
|
|
{{:., _, [mod, fun]}, meta, args} -> erl_to_ex(mod, fun, args, meta)
|
|
other -> other
|
|
end)
|
|
end
|
|
|
|
defp erl_to_ex(mod, fun, args, meta) do
|
|
case :elixir_rewrite.erl_to_ex(mod, fun, args) do
|
|
{Kernel, fun, args, _} -> {fun, meta, args}
|
|
{mod, fun, args, _} -> {{:., [], [mod, fun]}, meta, args}
|
|
end
|
|
end
|
|
|
|
defp blame_wrap(match?, ast), do: %{match?: match?, node: ast}
|
|
|
|
@doc """
|
|
Formats an exit. It returns a string.
|
|
|
|
Often there are errors/exceptions inside exits. Exits are often
|
|
wrapped by the caller and provide stacktraces too. This function
|
|
formats exits in a way to nicely show the exit reason, caller
|
|
and stacktrace.
|
|
"""
|
|
@spec format_exit(any) :: String.t()
|
|
def format_exit(reason) do
|
|
format_exit(reason, <<"\n ">>)
|
|
end
|
|
|
|
# 2-Tuple could be caused by an error if the second element is a stacktrace.
|
|
defp format_exit({exception, maybe_stacktrace} = reason, joiner)
|
|
when is_list(maybe_stacktrace) and maybe_stacktrace !== [] do
|
|
try do
|
|
Enum.map(maybe_stacktrace, &format_stacktrace_entry/1)
|
|
catch
|
|
:error, _ ->
|
|
# Not a stacktrace, was an exit.
|
|
format_exit_reason(reason)
|
|
else
|
|
formatted_stacktrace ->
|
|
# Assume a non-empty list formattable as stacktrace is a
|
|
# stacktrace, so exit was caused by an error.
|
|
message =
|
|
"an exception was raised:" <>
|
|
joiner <> format_banner(:error, exception, maybe_stacktrace)
|
|
|
|
Enum.join([message | formatted_stacktrace], joiner <> <<" ">>)
|
|
end
|
|
end
|
|
|
|
# :supervisor.start_link returns this error reason when it fails to init
|
|
# because a child's start_link raises.
|
|
defp format_exit({:shutdown, {:failed_to_start_child, child, {:EXIT, reason}}}, joiner) do
|
|
format_start_child(child, reason, joiner)
|
|
end
|
|
|
|
# :supervisor.start_link returns this error reason when it fails to init
|
|
# because a child's start_link returns {:error, reason}.
|
|
defp format_exit({:shutdown, {:failed_to_start_child, child, reason}}, joiner) do
|
|
format_start_child(child, reason, joiner)
|
|
end
|
|
|
|
# 2-Tuple could be an exit caused by mfa if second element is mfa, args
|
|
# must be a list of arguments - max length 255 due to max arity.
|
|
defp format_exit({reason2, {mod, fun, args}} = reason, joiner)
|
|
when length(args) < 256 do
|
|
try do
|
|
format_mfa(mod, fun, args)
|
|
catch
|
|
:error, _ ->
|
|
# Not an mfa, was an exit.
|
|
format_exit_reason(reason)
|
|
else
|
|
mfa ->
|
|
# Assume tuple formattable as an mfa is an mfa,
|
|
# so exit was caused by failed mfa.
|
|
"exited in: " <>
|
|
mfa <> joiner <> "** (EXIT) " <> format_exit(reason2, joiner <> <<" ">>)
|
|
end
|
|
end
|
|
|
|
defp format_exit(reason, _joiner) do
|
|
format_exit_reason(reason)
|
|
end
|
|
|
|
defp format_exit_reason(:normal), do: "normal"
|
|
defp format_exit_reason(:shutdown), do: "shutdown"
|
|
|
|
defp format_exit_reason({:shutdown, reason}) do
|
|
"shutdown: #{inspect(reason)}"
|
|
end
|
|
|
|
defp format_exit_reason(:calling_self), do: "process attempted to call itself"
|
|
defp format_exit_reason(:timeout), do: "time out"
|
|
defp format_exit_reason(:killed), do: "killed"
|
|
defp format_exit_reason(:noconnection), do: "no connection"
|
|
|
|
defp format_exit_reason(:noproc) do
|
|
"no process: the process is not alive or there's no process currently associated with the given name, possibly because its application isn't started"
|
|
end
|
|
|
|
defp format_exit_reason({:nodedown, node_name}) when is_atom(node_name) do
|
|
"no connection to #{node_name}"
|
|
end
|
|
|
|
# :gen_server exit reasons
|
|
|
|
defp format_exit_reason({:already_started, pid}) do
|
|
"already started: " <> inspect(pid)
|
|
end
|
|
|
|
defp format_exit_reason({:bad_return_value, value}) do
|
|
"bad return value: " <> inspect(value)
|
|
end
|
|
|
|
defp format_exit_reason({:bad_call, request}) do
|
|
"bad call: " <> inspect(request)
|
|
end
|
|
|
|
defp format_exit_reason({:bad_cast, request}) do
|
|
"bad cast: " <> inspect(request)
|
|
end
|
|
|
|
# :supervisor.start_link error reasons
|
|
|
|
# If value is a list will be formatted by mfa exit in format_exit/1
|
|
defp format_exit_reason({:bad_return, {mod, :init, value}})
|
|
when is_atom(mod) do
|
|
format_mfa(mod, :init, 1) <> " returned a bad value: " <> inspect(value)
|
|
end
|
|
|
|
defp format_exit_reason({:bad_start_spec, start_spec}) do
|
|
"bad child specification, invalid children: " <> inspect(start_spec)
|
|
end
|
|
|
|
defp format_exit_reason({:start_spec, start_spec}) do
|
|
"bad child specification, " <> format_sup_spec(start_spec)
|
|
end
|
|
|
|
defp format_exit_reason({:supervisor_data, data}) do
|
|
"bad supervisor configuration, " <> format_sup_data(data)
|
|
end
|
|
|
|
defp format_exit_reason(reason), do: inspect(reason)
|
|
|
|
defp format_start_child(child, reason, joiner) do
|
|
"shutdown: failed to start child: " <>
|
|
inspect(child) <> joiner <> "** (EXIT) " <> format_exit(reason, joiner <> <<" ">>)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_type, type}) do
|
|
"invalid type: " <> inspect(type)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_strategy, strategy}) do
|
|
"invalid strategy: " <> inspect(strategy)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_intensity, intensity}) do
|
|
"invalid max_restarts (intensity): " <> inspect(intensity)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_period, period}) do
|
|
"invalid max_seconds (period): " <> inspect(period)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_max_children, max_children}) do
|
|
"invalid max_children: " <> inspect(max_children)
|
|
end
|
|
|
|
defp format_sup_data({:invalid_extra_arguments, extra}) do
|
|
"invalid extra_arguments: " <> inspect(extra)
|
|
end
|
|
|
|
defp format_sup_data(other), do: "got: #{inspect(other)}"
|
|
|
|
defp format_sup_spec({:duplicate_child_name, id}) do
|
|
"""
|
|
more than one child specification has the id: #{inspect(id)}.
|
|
If using maps as child specifications, make sure the :id keys are unique.
|
|
If using a module or {module, arg} as child, use Supervisor.child_spec/2 to change the :id, for example:
|
|
|
|
children = [
|
|
Supervisor.child_spec({MyWorker, arg}, id: :my_worker_1),
|
|
Supervisor.child_spec({MyWorker, arg}, id: :my_worker_2)
|
|
]
|
|
"""
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_child_spec, child_spec}) do
|
|
"invalid child specification: #{inspect(child_spec)}"
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_child_type, type}) do
|
|
"invalid child type: #{inspect(type)}. Must be :worker or :supervisor."
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_mfa, mfa}) do
|
|
"invalid mfa: #{inspect(mfa)}"
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_restart_type, restart}) do
|
|
"invalid restart type: #{inspect(restart)}. Must be :permanent, :transient or :temporary."
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_shutdown, shutdown}) do
|
|
"invalid shutdown: #{inspect(shutdown)}. Must be an integer >= 0, :infinity or :brutal_kill."
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_module, mod}) do
|
|
"invalid module: #{inspect(mod)}. Must be an atom."
|
|
end
|
|
|
|
defp format_sup_spec({:invalid_modules, modules}) do
|
|
"invalid modules: #{inspect(modules)}. Must be a list of atoms or :dynamic."
|
|
end
|
|
|
|
defp format_sup_spec(other), do: "got: #{inspect(other)}"
|
|
|
|
@doc """
|
|
Receives a stacktrace entry and formats it into a string.
|
|
"""
|
|
@spec format_stacktrace_entry(stacktrace_entry) :: String.t()
|
|
def format_stacktrace_entry(entry)
|
|
|
|
# From Macro.Env.stacktrace
|
|
def format_stacktrace_entry({module, :__MODULE__, 0, location}) do
|
|
format_location(location) <> inspect(module) <> " (module)"
|
|
end
|
|
|
|
# From :elixir_compiler_*
|
|
def format_stacktrace_entry({_module, :__MODULE__, 1, location}) do
|
|
format_location(location) <> "(module)"
|
|
end
|
|
|
|
# From :elixir_compiler_*
|
|
def format_stacktrace_entry({_module, :__FILE__, 1, location}) do
|
|
format_location(location) <> "(file)"
|
|
end
|
|
|
|
def format_stacktrace_entry({module, fun, arity, location}) do
|
|
format_application(module) <> format_location(location) <> format_mfa(module, fun, arity)
|
|
end
|
|
|
|
def format_stacktrace_entry({fun, arity, location}) do
|
|
format_location(location) <> format_fa(fun, arity)
|
|
end
|
|
|
|
defp format_application(module) do
|
|
# We cannot use Application due to bootstrap issues
|
|
case :application.get_application(module) do
|
|
{:ok, app} ->
|
|
case :application.get_key(app, :vsn) do
|
|
{:ok, vsn} when is_list(vsn) ->
|
|
"(" <> Atom.to_string(app) <> " " <> List.to_string(vsn) <> ") "
|
|
|
|
_ ->
|
|
"(" <> Atom.to_string(app) <> ") "
|
|
end
|
|
|
|
:undefined ->
|
|
""
|
|
end
|
|
end
|
|
|
|
@doc """
|
|
Formats the stacktrace.
|
|
|
|
A stacktrace must be given as an argument. If not, the stacktrace
|
|
is retrieved from `Process.info/2`.
|
|
"""
|
|
@spec format_stacktrace(stacktrace | nil) :: String.t()
|
|
def format_stacktrace(trace \\ nil) do
|
|
trace =
|
|
if trace do
|
|
trace
|
|
else
|
|
case Process.info(self(), :current_stacktrace) do
|
|
{:current_stacktrace, t} -> Enum.drop(t, 3)
|
|
end
|
|
end
|
|
|
|
case trace do
|
|
[] -> "\n"
|
|
_ -> " " <> Enum.map_join(trace, "\n ", &format_stacktrace_entry(&1)) <> "\n"
|
|
end
|
|
end
|
|
|
|
@doc """
|
|
Receives an anonymous function and arity and formats it as
|
|
shown in stacktraces. The arity may also be a list of arguments.
|
|
|
|
## Examples
|
|
|
|
Exception.format_fa(fn -> nil end, 1)
|
|
#=> "#Function<...>/1"
|
|
|
|
"""
|
|
@spec format_fa(fun, arity) :: String.t()
|
|
def format_fa(fun, arity) when is_function(fun) do
|
|
"#{inspect(fun)}#{format_arity(arity)}"
|
|
end
|
|
|
|
@doc """
|
|
Receives a module, fun and arity and formats it
|
|
as shown in stacktraces. The arity may also be a list
|
|
of arguments.
|
|
|
|
## Examples
|
|
|
|
iex> Exception.format_mfa(Foo, :bar, 1)
|
|
"Foo.bar/1"
|
|
|
|
iex> Exception.format_mfa(Foo, :bar, [])
|
|
"Foo.bar()"
|
|
|
|
iex> Exception.format_mfa(nil, :bar, [])
|
|
"nil.bar()"
|
|
|
|
Anonymous functions are reported as -func/arity-anonfn-count-,
|
|
where func is the name of the enclosing function. Convert to
|
|
"anonymous fn in func/arity"
|
|
"""
|
|
@spec format_mfa(module, atom, arity_or_args) :: String.t()
|
|
def format_mfa(module, fun, arity) when is_atom(module) and is_atom(fun) do
|
|
case Code.Identifier.extract_anonymous_fun_parent(fun) do
|
|
{outer_name, outer_arity} ->
|
|
"anonymous fn#{format_arity(arity)} in " <>
|
|
"#{Macro.inspect_atom(:literal, module)}." <>
|
|
"#{Macro.inspect_atom(:remote_call, outer_name)}/#{outer_arity}"
|
|
|
|
:error ->
|
|
"#{Macro.inspect_atom(:literal, module)}." <>
|
|
"#{Macro.inspect_atom(:remote_call, fun)}#{format_arity(arity)}"
|
|
end
|
|
end
|
|
|
|
defp format_arity(arity) when is_list(arity) do
|
|
inspected = for x <- arity, do: inspect(x)
|
|
"(#{Enum.join(inspected, ", ")})"
|
|
end
|
|
|
|
defp format_arity(arity) when is_integer(arity) do
|
|
"/" <> Integer.to_string(arity)
|
|
end
|
|
|
|
@doc """
|
|
Formats the given `file` and `line` as shown in stacktraces.
|
|
|
|
If any of the values are `nil`, they are omitted.
|
|
|
|
## Examples
|
|
|
|
iex> Exception.format_file_line("foo", 1)
|
|
"foo:1:"
|
|
|
|
iex> Exception.format_file_line("foo", nil)
|
|
"foo:"
|
|
|
|
iex> Exception.format_file_line(nil, nil)
|
|
""
|
|
|
|
"""
|
|
@spec format_file_line(String.t() | nil, non_neg_integer | nil, String.t()) :: String.t()
|
|
def format_file_line(file, line, suffix \\ "") do
|
|
cond do
|
|
is_nil(file) -> ""
|
|
is_nil(line) or line == 0 -> "#{file}:#{suffix}"
|
|
true -> "#{file}:#{line}:#{suffix}"
|
|
end
|
|
end
|
|
|
|
@doc """
|
|
Formats the given `file`, `line`, and `column` as shown in stacktraces.
|
|
|
|
If any of the values are `nil`, they are omitted.
|
|
|
|
## Examples
|
|
|
|
iex> Exception.format_file_line_column("foo", 1, 2)
|
|
"foo:1:2:"
|
|
|
|
iex> Exception.format_file_line_column("foo", 1, nil)
|
|
"foo:1:"
|
|
|
|
iex> Exception.format_file_line_column("foo", nil, nil)
|
|
"foo:"
|
|
|
|
iex> Exception.format_file_line_column("foo", nil, 2)
|
|
"foo:"
|
|
|
|
iex> Exception.format_file_line_column(nil, nil, nil)
|
|
""
|
|
|
|
"""
|
|
@spec format_file_line_column(
|
|
String.t() | nil,
|
|
non_neg_integer | nil,
|
|
non_neg_integer | nil,
|
|
String.t()
|
|
) :: String.t()
|
|
def format_file_line_column(file, line, column, suffix \\ "") do
|
|
cond do
|
|
is_nil(file) -> ""
|
|
is_nil(line) or line == 0 -> "#{file}:#{suffix}"
|
|
is_nil(column) or column == 0 -> "#{file}:#{line}:#{suffix}"
|
|
true -> "#{file}:#{line}:#{column}:#{suffix}"
|
|
end
|
|
end
|
|
|
|
defp format_location(opts) when is_list(opts) do
|
|
case opts[:column] do
|
|
nil -> format_file_line(Keyword.get(opts, :file), Keyword.get(opts, :line), " ")
|
|
col -> format_file_line_column(Keyword.get(opts, :file), Keyword.get(opts, :line), col, " ")
|
|
end
|
|
end
|
|
|
|
@doc false
|
|
def format_delimiter(delimiter) do
|
|
if delimiter |> Atom.to_string() |> String.contains?(["\"", "'"]),
|
|
do: delimiter,
|
|
else: ~s("#{delimiter}")
|
|
end
|
|
|
|
@doc false
|
|
def format_snippet(
|
|
{start_line, _start_column} = start_pos,
|
|
{end_line, end_column} = end_pos,
|
|
description,
|
|
file,
|
|
lines,
|
|
start_message,
|
|
end_message
|
|
)
|
|
when start_line < end_line do
|
|
max_digits = digits(end_line)
|
|
general_padding = max(2, max_digits) + 1
|
|
padding = n_spaces(general_padding)
|
|
|
|
relevant_lines =
|
|
if end_line - start_line < 5 do
|
|
line_range(lines, start_pos, end_pos, padding, max_digits, start_message, end_message)
|
|
else
|
|
trimmed_inbetween_lines(
|
|
lines,
|
|
start_pos,
|
|
end_pos,
|
|
padding,
|
|
max_digits,
|
|
start_message,
|
|
end_message
|
|
)
|
|
end
|
|
|
|
"""
|
|
#{padding}#{red("error:")} #{pad_message(description, padding)}
|
|
#{padding}│
|
|
#{relevant_lines}
|
|
#{padding}│
|
|
#{padding}└─ #{Path.relative_to_cwd(file)}:#{end_line}:#{end_column}\
|
|
"""
|
|
end
|
|
|
|
def format_snippet(
|
|
{start_line, start_column},
|
|
{end_line, end_column},
|
|
description,
|
|
file,
|
|
lines,
|
|
start_message,
|
|
end_message
|
|
)
|
|
when start_line == end_line do
|
|
max_digits = digits(end_line)
|
|
general_padding = max(2, max_digits) + 1
|
|
padding = n_spaces(general_padding)
|
|
formatted_line = [line_padding(end_line, max_digits), to_string(end_line), " │ ", hd(lines)]
|
|
|
|
mismatched_closing_line =
|
|
[
|
|
n_spaces(start_column - 1),
|
|
red("│"),
|
|
format_end_message(end_column - start_column, end_message)
|
|
]
|
|
|
|
unclosed_delimiter_line =
|
|
[padding, " │ ", format_start_message(start_column, start_message)]
|
|
|
|
below_line = [padding, " │ ", mismatched_closing_line, "\n", unclosed_delimiter_line]
|
|
|
|
"""
|
|
#{padding}#{red("error:")} #{pad_message(description, padding)}
|
|
#{padding}│
|
|
#{formatted_line}
|
|
#{below_line}
|
|
#{padding}│
|
|
#{padding}└─ #{Path.relative_to_cwd(file)}:#{end_line}:#{end_column}\
|
|
"""
|
|
end
|
|
|
|
defp line_padding(line_number, max_digits) do
|
|
line_digits = digits(line_number)
|
|
|
|
spacing =
|
|
if line_digits == 1 do
|
|
max(2, max_digits)
|
|
else
|
|
max_digits - line_digits + 1
|
|
end
|
|
|
|
n_spaces(spacing)
|
|
end
|
|
|
|
defp n_spaces(n), do: String.duplicate(" ", n)
|
|
|
|
defp digits(number, acc \\ 1)
|
|
defp digits(number, acc) when number < 10, do: acc
|
|
defp digits(number, acc), do: digits(div(number, 10), acc + 1)
|
|
|
|
defp trimmed_inbetween_lines(
|
|
lines,
|
|
{start_line, start_column},
|
|
{end_line, end_column},
|
|
padding,
|
|
max_digits,
|
|
start_message,
|
|
end_message
|
|
) do
|
|
start_padding = line_padding(start_line, max_digits)
|
|
end_padding = line_padding(end_line, max_digits)
|
|
first_line = hd(lines)
|
|
last_line = List.last(lines)
|
|
|
|
"""
|
|
#{start_padding}#{start_line} │ #{first_line}
|
|
#{padding}│ #{format_start_message(start_column, start_message)}
|
|
...
|
|
#{end_padding}#{end_line} │ #{last_line}
|
|
#{padding}│ #{format_end_message(end_column, end_message)}\
|
|
"""
|
|
end
|
|
|
|
defp line_range(
|
|
lines,
|
|
{start_line, start_column},
|
|
{end_line, end_column},
|
|
padding,
|
|
max_digits,
|
|
start_message,
|
|
end_message
|
|
) do
|
|
Enum.zip_with(lines, start_line..end_line, fn line, line_number ->
|
|
line_padding = line_padding(line_number, max_digits)
|
|
|
|
cond do
|
|
line_number == start_line ->
|
|
[
|
|
line_padding,
|
|
to_string(line_number),
|
|
" │ ",
|
|
line,
|
|
"\n",
|
|
padding,
|
|
" │ ",
|
|
format_start_message(start_column, start_message)
|
|
]
|
|
|
|
line_number == end_line ->
|
|
[
|
|
line_padding,
|
|
to_string(line_number),
|
|
" │ ",
|
|
line,
|
|
"\n",
|
|
padding,
|
|
" │ ",
|
|
format_end_message(end_column, end_message)
|
|
]
|
|
|
|
true ->
|
|
[line_padding, to_string(line_number), " │ ", line]
|
|
end
|
|
end)
|
|
|> Enum.intersperse("\n")
|
|
end
|
|
|
|
defp format_end_message(end_column, message),
|
|
do: [
|
|
n_spaces(end_column - 1),
|
|
red(message)
|
|
]
|
|
|
|
defp format_start_message(start_column, message),
|
|
do: [n_spaces(start_column - 1), red(message)]
|
|
|
|
defp pad_message(message, padding), do: String.replace(message, "\n", "\n #{padding}")
|
|
|
|
defp red(string) do
|
|
if IO.ANSI.enabled?() do
|
|
[IO.ANSI.red(), string, IO.ANSI.reset()]
|
|
else
|
|
string
|
|
end
|
|
end
|
|
end
|
|
|
|
# Some exceptions implement "message/1" instead of "exception/1" mostly
|
|
# for bootstrap reasons. It is recommended for applications to implement
|
|
# "exception/1" instead of "message/1" as described in "defexception/1"
|
|
# docs.
|
|
|
|
defmodule RuntimeError do
|
|
@moduledoc """
|
|
An exception for a generic runtime error.
|
|
|
|
This is the exception that `raise/1` raises when you pass it only a string as
|
|
a message:
|
|
|
|
iex> raise "oops!"
|
|
** (RuntimeError) oops!
|
|
|
|
You should use this exceptions sparingly, since most of the time it might be
|
|
better to define your own exceptions specific to your application or library.
|
|
Sometimes, however, there are situations in which you don't expect a condition to
|
|
happen, but you want to give a meaningful error message if it does. In those cases,
|
|
`RuntimeError` can be a good choice.
|
|
|
|
## Fields
|
|
|
|
`RuntimeError` exceptions have a single field, `:message` (a `t:String.t/0`),
|
|
which is public and can be accessed freely when reading or creating `RuntimeError`
|
|
exceptions.
|
|
"""
|
|
|
|
defexception message: "runtime error"
|
|
end
|
|
|
|
defmodule ArgumentError do
|
|
@moduledoc """
|
|
An exception raised when an argument to a function is invalid.
|
|
|
|
You can raise this exception when you want to signal that an argument to
|
|
a function is invalid. For example, this exception is raised when calling
|
|
`Integer.to_string/1` with an invalid argument:
|
|
|
|
iex> Integer.to_string(1.0)
|
|
** (ArgumentError) errors were found at the given arguments:
|
|
...
|
|
|
|
`ArgumentError` exceptions have a single field, `:message` (a `t:String.t/0`),
|
|
which is public and can be accessed freely when reading or creating `ArgumentError`
|
|
exceptions.
|
|
"""
|
|
|
|
defexception message: "argument error"
|
|
end
|
|
|
|
defmodule ArithmeticError do
|
|
@moduledoc """
|
|
An exception raised on invalid arithmetic operations.
|
|
|
|
For example, this exception is raised if you divide by `0`:
|
|
|
|
iex> 1 / 0
|
|
** (ArithmeticError) bad argument in arithmetic expression
|
|
"""
|
|
|
|
defexception message: "bad argument in arithmetic expression"
|
|
|
|
@unary_ops [:+, :-]
|
|
@binary_ops [:+, :-, :*, :/]
|
|
@binary_funs [:div, :rem]
|
|
@bitwise_binary_funs [:band, :bor, :bxor, :bsl, :bsr]
|
|
|
|
@impl true
|
|
def blame(%{message: message} = exception, [{:erlang, fun, args, _} | _] = stacktrace) do
|
|
message =
|
|
message <>
|
|
case {fun, args} do
|
|
{op, [a]} when op in @unary_ops ->
|
|
": #{op}(#{inspect(a)})"
|
|
|
|
{op, [a, b]} when op in @binary_ops ->
|
|
": #{inspect(a)} #{op} #{inspect(b)}"
|
|
|
|
{fun, [a, b]} when fun in @binary_funs ->
|
|
": #{fun}(#{inspect(a)}, #{inspect(b)})"
|
|
|
|
{fun, [a, b]} when fun in @bitwise_binary_funs ->
|
|
": Bitwise.#{fun}(#{inspect(a)}, #{inspect(b)})"
|
|
|
|
{:bnot, [a]} ->
|
|
": Bitwise.bnot(#{inspect(a)})"
|
|
|
|
_ ->
|
|
""
|
|
end
|
|
|
|
{%{exception | message: message}, stacktrace}
|
|
end
|
|
|
|
def blame(exception, stacktrace) do
|
|
{exception, stacktrace}
|
|
end
|
|
end
|
|
|
|
defmodule SystemLimitError do
|
|
@moduledoc """
|
|
An exception raised when a system limit has been reached.
|
|
|
|
For example, this can happen if you try to create an atom that is too large:
|
|
|
|
iex> String.to_atom(String.duplicate("a", 100_000))
|
|
** (SystemLimitError) a system limit has been reached
|
|
"""
|
|
|
|
defexception message: "a system limit has been reached"
|
|
end
|
|
|
|
defmodule MismatchedDelimiterError do
|
|
@moduledoc """
|
|
An exception raised when a mismatched delimiter is found when parsing code.
|
|
|
|
For example:
|
|
|
|
iex> Code.eval_string("[1, 2, 3}")
|
|
** (MismatchedDelimiterError) mismatched delimiter found on nofile:1:9:
|
|
...
|
|
|
|
The following fields of this exceptions are public and can be accessed freely:
|
|
|
|
* `:file` (`t:Path.t/0` or `nil`) - the file where the error occurred, or `nil` if
|
|
the error occurred in code that did not come from a file
|
|
* `:line` - the line for the opening delimiter
|
|
* `:column` - the column for the opening delimiter
|
|
* `:end_line` - the line for the mismatched closing delimiter
|
|
* `:end_column` - the column for the mismatched closing delimiter
|
|
* `:opening_delimiter` - an atom representing the opening delimiter
|
|
* `:closing_delimiter` - an atom representing the mismatched closing delimiter
|
|
* `:expected_delimiter` - an atom representing the closing delimiter
|
|
* `:description` - a description of the mismatched delimiter error
|
|
"""
|
|
|
|
defexception [
|
|
:file,
|
|
:line,
|
|
:column,
|
|
:end_line,
|
|
:end_column,
|
|
:opening_delimiter,
|
|
:closing_delimiter,
|
|
:expected_delimiter,
|
|
:snippet,
|
|
description: "mismatched delimiter error"
|
|
]
|
|
|
|
@impl true
|
|
def message(%{
|
|
line: start_line,
|
|
column: start_column,
|
|
end_line: end_line,
|
|
end_column: end_column,
|
|
description: description,
|
|
expected_delimiter: expected_delimiter,
|
|
file: file,
|
|
snippet: snippet
|
|
}) do
|
|
start_pos = {start_line, start_column}
|
|
end_pos = {end_line, end_column}
|
|
lines = String.split(snippet, "\n")
|
|
expected_delimiter = Exception.format_delimiter(expected_delimiter)
|
|
|
|
start_message = "└ unclosed delimiter"
|
|
end_message = ~s/└ mismatched closing delimiter (expected #{expected_delimiter})/
|
|
|
|
snippet =
|
|
Exception.format_snippet(
|
|
start_pos,
|
|
end_pos,
|
|
description,
|
|
file,
|
|
lines,
|
|
start_message,
|
|
end_message
|
|
)
|
|
|
|
format_message(file, end_line, end_column, snippet)
|
|
end
|
|
|
|
defp format_message(file, line, column, message) do
|
|
location = Exception.format_file_line_column(Path.relative_to_cwd(file), line, column)
|
|
"mismatched delimiter found on " <> location <> "\n" <> message
|
|
end
|
|
end
|
|
|
|
defmodule SyntaxError do
|
|
@moduledoc """
|
|
An exception raised when there's a syntax error when parsing code.
|
|
|
|
For example:
|
|
|
|
iex> Code.eval_string("5 + 5h")
|
|
** (SyntaxError) invalid syntax found on nofile:1:5:
|
|
...
|
|
|
|
The following fields of this exceptions are public and can be accessed freely:
|
|
|
|
* `:file` (`t:Path.t/0` or `nil`) - the file where the error occurred, or `nil` if
|
|
the error occurred in code that did not come from a file
|
|
* `:line` - the line where the error occurred
|
|
* `:column` - the column where the error occurred
|
|
* `:description` - a description of the syntax error
|
|
"""
|
|
|
|
defexception [:file, :line, :column, :snippet, description: "syntax error"]
|
|
|
|
@impl true
|
|
def message(%{
|
|
file: file,
|
|
line: line,
|
|
column: column,
|
|
description: description,
|
|
snippet: snippet
|
|
})
|
|
when not is_nil(snippet) and not is_nil(column) do
|
|
snippet =
|
|
:elixir_errors.format_snippet(:error, {line, column}, file, description, snippet, %{})
|
|
|
|
format_message(file, line, column, snippet)
|
|
end
|
|
|
|
@impl true
|
|
def message(%{
|
|
file: file,
|
|
line: line,
|
|
column: column,
|
|
description: description
|
|
}) do
|
|
snippet =
|
|
:elixir_errors.format_snippet(:error, {line, column}, file, description, nil, %{})
|
|
|
|
padded = " " <> String.replace(snippet, "\n", "\n ")
|
|
format_message(file, line, column, padded)
|
|
end
|
|
|
|
defp format_message(file, line, column, message) do
|
|
location = Exception.format_file_line_column(Path.relative_to_cwd(file), line, column)
|
|
"invalid syntax found on " <> location <> "\n" <> message
|
|
end
|
|
end
|
|
|
|
defmodule TokenMissingError do
|
|
@moduledoc """
|
|
An exception raised when a token is missing when parsing code.
|
|
|
|
For example:
|
|
|
|
iex> Code.eval_string("[1, 2, 3")
|
|
** (TokenMissingError) token missing on nofile:1:9:
|
|
...
|
|
|
|
The following fields of this exceptions are public and can be accessed freely:
|
|
|
|
* `:file` (`t:Path.t/0` or `nil`) - the file where the error occurred, or `nil` if
|
|
the error occurred in code that did not come from a file
|
|
* `:line` - the line for the opening delimiter
|
|
* `:column` - the column for the opening delimiter
|
|
* `:end_line` - the line for the end of the string
|
|
* `:end_column` - the column for the end of the string
|
|
* `:opening_delimiter` - an atom representing the opening delimiter
|
|
* `:expected_delimiter` - an atom representing the expected delimiter
|
|
* `:description` - a description of the missing token error
|
|
|
|
This is mostly raised by Elixir tooling when compiling and evaluating code.
|
|
"""
|
|
|
|
defexception [
|
|
:file,
|
|
:line,
|
|
:column,
|
|
:end_line,
|
|
:end_column,
|
|
:snippet,
|
|
:opening_delimiter,
|
|
:expected_delimiter,
|
|
description: "expression is incomplete"
|
|
]
|
|
|
|
@impl true
|
|
def message(%{
|
|
file: file,
|
|
line: line,
|
|
column: column,
|
|
end_line: end_line,
|
|
description: description,
|
|
expected_delimiter: expected_delimiter,
|
|
snippet: snippet
|
|
})
|
|
when not is_nil(snippet) and not is_nil(column) and not is_nil(end_line) do
|
|
{trimmed, [last_line | _] = reversed_lines} =
|
|
snippet
|
|
|> String.split("\n")
|
|
|> Enum.reverse()
|
|
|> Enum.split_while(&(&1 == ""))
|
|
|
|
end_line = end_line - length(trimmed)
|
|
end_column = String.length(last_line) + 1
|
|
|
|
start_pos = {line, column}
|
|
end_pos = {end_line, end_column}
|
|
expected_delimiter = Exception.format_delimiter(expected_delimiter)
|
|
|
|
start_message = ~s/└ unclosed delimiter/
|
|
end_message = ~s/└ missing closing delimiter (expected #{expected_delimiter})/
|
|
|
|
snippet =
|
|
Exception.format_snippet(
|
|
start_pos,
|
|
end_pos,
|
|
description,
|
|
file,
|
|
Enum.reverse(reversed_lines),
|
|
start_message,
|
|
end_message
|
|
)
|
|
|
|
format_message(file, end_line, end_column, snippet)
|
|
end
|
|
|
|
@impl true
|
|
def message(%{
|
|
file: file,
|
|
line: line,
|
|
column: column,
|
|
snippet: snippet,
|
|
description: description
|
|
}) do
|
|
snippet =
|
|
:elixir_errors.format_snippet(:error, {line, column}, file, description, snippet, %{})
|
|
|
|
format_message(file, line, column, snippet)
|
|
end
|
|
|
|
defp format_message(file, line, column, message) do
|
|
location = Exception.format_file_line_column(Path.relative_to_cwd(file), line, column)
|
|
"token missing on " <> location <> "\n" <> message
|
|
end
|
|
end
|
|
|
|
defmodule CompileError do
|
|
@moduledoc """
|
|
An exception raised when there's an error when compiling code.
|
|
|
|
For example:
|
|
|
|
1 = y
|
|
** (CompileError) iex:1: undefined variable "y"
|
|
|
|
The following fields of this exceptions are public and can be accessed freely:
|
|
|
|
* `:file` (`t:Path.t/0` or `nil`) - the file where the error occurred, or `nil` if
|
|
the error occurred in code that did not come from a file
|
|
* `:line` (`t:non_neg_integer/0`) - the line where the error occurred
|
|
* `:description` (`t:String.t/0`) - a description of the compile error
|
|
|
|
This is mostly raised by Elixir tooling when compiling and evaluating code.
|
|
"""
|
|
|
|
defexception [:file, :line, description: "compile error"]
|
|
|
|
@impl true
|
|
def message(%{file: file, line: line, description: description}) do
|
|
case Exception.format_file_line(file && Path.relative_to_cwd(file), line) do
|
|
"" -> description
|
|
formatted -> formatted <> " " <> description
|
|
end
|
|
end
|
|
end
|
|
|
|
defmodule Kernel.TypespecError do
|
|
@moduledoc """
|
|
An exception raised when there's an error in a typespec.
|
|
|
|
For example, if your typespec definition points to an invalid type, you get an exception:
|
|
|
|
@type my_type :: intger()
|
|
|
|
will raise:
|
|
|
|
** (Kernel.TypespecError) type intger/0 undefined
|
|
|
|
The following fields of this exceptions are public and can be accessed freely:
|
|
|
|
* `:file` (`t:Path.t/0` or `nil`) - the file where the error occurred, or `nil` if
|
|
the error occurred in code that did not come from a file
|
|
* `:line` (`t:non_neg_integer/0`) - the line where the error occurred
|
|
"""
|
|
|
|
defexception [:file, :line, :description]
|
|
|
|
@impl true
|
|
def message(%{file: file, line: line, description: description}) do
|
|
case Exception.format_file_line(file && Path.relative_to_cwd(file), line) do
|
|
"" -> description
|
|
formatted -> formatted <> " " <> description
|
|
end
|
|
end
|
|
end
|
|
|
|
defmodule BadFunctionError do
|
|
@moduledoc """
|
|
An exception raised when a function is expected, but something else was given.
|
|
|
|
For example:
|
|
|
|
iex> value = "hello"
|
|
iex> value.()
|
|
** (BadFunctionError) expected a function, got: "hello"
|
|
"""
|
|
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(%{term: term}) when is_function(term) do
|
|
"function #{inspect(term)} is invalid, likely because it points to an old version of the code"
|
|
end
|
|
|
|
def message(exception) do
|
|
"expected a function, got: #{inspect(exception.term)}"
|
|
end
|
|
end
|
|
|
|
defmodule BadMapError do
|
|
@moduledoc """
|
|
An exception raised when a map is expected, but something else was given.
|
|
|
|
For example:
|
|
|
|
iex> value = "hello"
|
|
iex> %{value | key: "value"}
|
|
** (BadMapError) expected a map, got:
|
|
...
|
|
"""
|
|
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"expected a map, got:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule BadBooleanError do
|
|
@moduledoc """
|
|
An exception raised when a boolean is expected, but something else was given.
|
|
|
|
This exception is raised by `and` and `or` when the first argument is not a boolean:
|
|
|
|
iex> 123 and true
|
|
** (BadBooleanError) expected a boolean on left-side of "and", got:
|
|
...
|
|
"""
|
|
|
|
defexception [:term, :operator]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"expected a boolean on left-side of \"#{exception.operator}\", got:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule MatchError do
|
|
@moduledoc """
|
|
An exception raised when a pattern match (`=/2`) fails.
|
|
|
|
For example:
|
|
|
|
iex> [_ | _] = []
|
|
** (MatchError) no match of right hand side value:
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:term` (`t:term/0`) - the term that did not match the pattern
|
|
|
|
"""
|
|
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"no match of right hand side value:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule CaseClauseError do
|
|
@moduledoc """
|
|
An exception raised when a term in a `case/2` expression
|
|
does not match any of the defined `->` clauses.
|
|
|
|
For example:
|
|
|
|
iex> case System.unique_integer() do
|
|
...> bin when is_binary(bin) -> :oops
|
|
...> :ok -> :neither_this_one
|
|
...> end
|
|
** (CaseClauseError) no case clause matching:
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:term` (`t:term/0`) - the term that did not match any of the clauses
|
|
"""
|
|
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"no case clause matching:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule WithClauseError do
|
|
@moduledoc """
|
|
An exception raised when a term in a `with/1` expression
|
|
does not match any of the defined `->` clauses in its `else`.
|
|
|
|
For example, this exception gets raised for a `with/1` like the following, because
|
|
the `{:ok, 2}` term does not match the `:error` or `{:error, _}` clauses in the
|
|
`else`:
|
|
|
|
iex> with {:ok, 1} <- {:ok, 2} do
|
|
...> :woah
|
|
...> else
|
|
...> :error -> :error
|
|
...> {:error, _} -> :error
|
|
...> end
|
|
** (WithClauseError) no with clause matching:
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:term` (`t:term/0`) - the term that did not match any of the clauses
|
|
"""
|
|
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"no with clause matching:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule CondClauseError do
|
|
@moduledoc """
|
|
An exception raised when no clauses in a `cond/1` expression evaluate to a truthy value.
|
|
|
|
For example, this exception gets raised for a `cond/1` like the following:
|
|
|
|
iex> cond do
|
|
...> 1 + 1 == 3 -> :woah
|
|
...> nil -> "yeah this won't happen"
|
|
...> end
|
|
** (CondClauseError) no cond clause evaluated to a truthy value
|
|
"""
|
|
|
|
defexception []
|
|
|
|
@impl true
|
|
def message(_exception) do
|
|
"no cond clause evaluated to a truthy value"
|
|
end
|
|
end
|
|
|
|
defmodule TryClauseError do
|
|
@moduledoc """
|
|
An exception raised when none of the `else` clauses in a `try/1` match.
|
|
|
|
For example:
|
|
|
|
iex> try do
|
|
...> :ok
|
|
...> rescue
|
|
...> e -> e
|
|
...> else
|
|
...> # :ok -> :ok is missing
|
|
...> :not_ok -> :not_ok
|
|
...> end
|
|
** (TryClauseError) no try clause matching:
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:term` (`t:term/0`) - the term that did not match any of the clauses
|
|
|
|
"""
|
|
defexception [:term]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
Exception.__format_message_with_term__(
|
|
"no try clause matching:",
|
|
exception.term
|
|
)
|
|
end
|
|
end
|
|
|
|
defmodule BadArityError do
|
|
@moduledoc """
|
|
An exception raised when a function is called with the wrong number of arguments.
|
|
|
|
For example:
|
|
|
|
my_function = fn x, y -> x + y end
|
|
my_function.(42)
|
|
** (BadArityError) #Function<41.39164016/2 in :erl_eval.expr/6> with arity 2 called with 1 argument (42)
|
|
"""
|
|
|
|
defexception [:function, :args]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
fun = exception.function
|
|
args = exception.args
|
|
insp = Enum.map_join(args, ", ", &inspect/1)
|
|
{:arity, arity} = Function.info(fun, :arity)
|
|
"#{inspect(fun)} with arity #{arity} called with #{count(length(args), insp)}"
|
|
end
|
|
|
|
defp count(0, _insp), do: "no arguments"
|
|
defp count(1, insp), do: "1 argument (#{insp})"
|
|
defp count(x, insp), do: "#{x} arguments (#{insp})"
|
|
end
|
|
|
|
defmodule UndefinedFunctionError do
|
|
@moduledoc """
|
|
An exception raised when a function is invoked that is not defined.
|
|
|
|
For example:
|
|
|
|
# Let's use apply/3 as otherwise Elixir emits a compile-time warning
|
|
iex> apply(String, :non_existing_fun, ["hello"])
|
|
** (UndefinedFunctionError) function String.non_existing_fun/1 is undefined or private
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:module` (`t:module/0`) - the module name
|
|
* `:function` (`t:atom/0`) - the function name
|
|
* `:arity` (`t:non_neg_integer/0`) - the arity of the function
|
|
"""
|
|
|
|
@function_threshold 0.77
|
|
@max_suggestions 5
|
|
defexception [:module, :function, :arity, :reason, :message]
|
|
|
|
@impl true
|
|
def message(%{message: nil} = exception) do
|
|
%{reason: reason, module: module, function: function, arity: arity} = exception
|
|
{message, hint_type} = message(reason, module, function, arity)
|
|
message <> if(hint_type == :suggest_module, do: hint_for_missing_alias(module), else: "")
|
|
end
|
|
|
|
def message(%{message: message}) do
|
|
message
|
|
end
|
|
|
|
defp message(nil, module, function, arity) do
|
|
cond do
|
|
is_nil(function) or is_nil(arity) ->
|
|
{"undefined function", :suggest_module}
|
|
|
|
is_nil(module) ->
|
|
formatted_fun = Exception.format_mfa(module, function, arity)
|
|
{"function #{formatted_fun} is undefined", :suggest_module}
|
|
|
|
function_exported?(module, :module_info, 0) ->
|
|
message(:"function not exported", module, function, arity)
|
|
|
|
true ->
|
|
message(:"module could not be loaded", module, function, arity)
|
|
end
|
|
end
|
|
|
|
defp message(:"module could not be loaded", module, function, arity) do
|
|
formatted_fun = Exception.format_mfa(module, function, arity)
|
|
|
|
{"function #{formatted_fun} is undefined (module #{inspect(module)} is not available)",
|
|
:suggest_module}
|
|
end
|
|
|
|
defp message(:"function not exported", module, function, arity) do
|
|
formatted_fun = Exception.format_mfa(module, function, arity)
|
|
{"function #{formatted_fun} is undefined or private", :suggest_function}
|
|
end
|
|
|
|
defp message(:"undefined local", nil, function, arity) do
|
|
{"function #{function}/#{arity} is undefined (there is no such import)", :no_hint}
|
|
end
|
|
|
|
defp message(reason, module, function, arity) do
|
|
formatted_fun = Exception.format_mfa(module, function, arity)
|
|
{"function #{formatted_fun} is undefined (#{reason})", :suggest_module}
|
|
end
|
|
|
|
@impl true
|
|
def blame(exception, stacktrace) do
|
|
%{reason: reason, module: module, function: function, arity: arity} = exception
|
|
{message, hint_type} = message(reason, module, function, arity)
|
|
message = message <> hint(module, function, arity, hint_type)
|
|
{%{exception | message: message}, stacktrace}
|
|
end
|
|
|
|
defp hint(_, _, _, :no_hint), do: ""
|
|
|
|
defp hint(nil, _function, 0, _hint_type) do
|
|
". If you are using the dot syntax, such as module.function(), " <>
|
|
"make sure the left-hand side of the dot is a module atom"
|
|
end
|
|
|
|
defp hint(module, function, arity, :suggest_function) do
|
|
hint_for_behaviour(module, function, arity) <>
|
|
hint_for_loaded_module(module, function, arity)
|
|
end
|
|
|
|
defp hint(module, function, arity, :suggest_module) do
|
|
hint_for_missing_module(module, function, arity)
|
|
end
|
|
|
|
defp hint_for_missing_alias(module) do
|
|
with "Elixir." <> rest <- Atom.to_string(module),
|
|
false <- rest =~ "." do
|
|
". Make sure the module name is correct and has been specified in full (or that an alias has been defined)"
|
|
else
|
|
_ -> ""
|
|
end
|
|
end
|
|
|
|
@doc false
|
|
def hint_for_missing_module(module, function, arity) do
|
|
downcased_module = downcase_module_name(module)
|
|
stripped_module = module |> Atom.to_string() |> String.replace_leading("Elixir.", "")
|
|
|
|
candidates =
|
|
for {name, _, _} = candidate <- :code.all_available(),
|
|
downcase_module_name(name) == downcased_module or
|
|
String.ends_with?(List.to_string(name), stripped_module),
|
|
{:module, module} <- [load_module(candidate)],
|
|
function_exported?(module, function, arity),
|
|
do: module
|
|
|
|
if candidates != [] do
|
|
suggestions =
|
|
candidates
|
|
|> Enum.take(@max_suggestions)
|
|
|> Enum.sort(:asc)
|
|
|> Enum.map(fn module ->
|
|
["\n * ", Exception.format_mfa(module, function, arity)]
|
|
end)
|
|
|
|
". Did you mean:\n#{suggestions}\n"
|
|
else
|
|
hint_for_missing_alias(module)
|
|
end
|
|
end
|
|
|
|
defp load_module({name, _path, _loaded?}) do
|
|
name
|
|
|> List.to_atom()
|
|
|> Code.ensure_loaded()
|
|
end
|
|
|
|
defp downcase_module_name(module) do
|
|
module
|
|
|> to_string()
|
|
|> String.downcase(:ascii)
|
|
end
|
|
|
|
@doc false
|
|
def hint_for_loaded_module(module, function, arity) do
|
|
cond do
|
|
macro_exported?(module, function, arity) ->
|
|
". However, there is a macro with the same name and arity. " <>
|
|
"Be sure to require #{inspect(module)} if you intend to invoke this macro"
|
|
|
|
message = otp_obsolete(module, function, arity) ->
|
|
", #{message}"
|
|
|
|
true ->
|
|
IO.iodata_to_binary(did_you_mean(module, function))
|
|
end
|
|
end
|
|
|
|
defp otp_obsolete(module, function, arity) do
|
|
case :otp_internal.obsolete(module, function, arity) do
|
|
{:removed, [_ | _] = string} -> string
|
|
_ -> nil
|
|
end
|
|
end
|
|
|
|
defp hint_for_behaviour(module, function, arity) do
|
|
case behaviours_for(module) do
|
|
[] ->
|
|
""
|
|
|
|
behaviours ->
|
|
case Enum.find(behaviours, &expects_callback?(&1, function, arity)) do
|
|
nil -> ""
|
|
behaviour -> ", but the behaviour #{inspect(behaviour)} expects it to be present"
|
|
end
|
|
end
|
|
rescue
|
|
# In case the module was removed while we are computing this
|
|
UndefinedFunctionError -> ""
|
|
end
|
|
|
|
defp behaviours_for(module) do
|
|
:attributes
|
|
|> module.module_info()
|
|
|> Keyword.get(:behaviour, [])
|
|
end
|
|
|
|
defp expects_callback?(behaviour, function, arity) do
|
|
callbacks =
|
|
behaviour.behaviour_info(:callbacks) -- behaviour.behaviour_info(:optional_callbacks)
|
|
|
|
Enum.member?(callbacks, {function, arity})
|
|
end
|
|
|
|
## Shared helpers across hints
|
|
|
|
defp did_you_mean(module, function) do
|
|
exports = exports_for(module)
|
|
|
|
result =
|
|
case Keyword.take(exports, [function]) do
|
|
[] ->
|
|
candidates = exports -- deprecated_functions_for(module)
|
|
base = Atom.to_string(function)
|
|
|
|
for {key, val} <- candidates,
|
|
dist = String.jaro_distance(base, Atom.to_string(key)),
|
|
dist >= @function_threshold,
|
|
do: {dist, key, val}
|
|
|
|
arities ->
|
|
for {key, val} <- arities, do: {1.0, key, val}
|
|
end
|
|
|> Enum.sort(&(elem(&1, 0) >= elem(&2, 0)))
|
|
|> Enum.take(@max_suggestions)
|
|
|> Enum.sort(&(elem(&1, 1) <= elem(&2, 1)))
|
|
|
|
case result do
|
|
[] -> []
|
|
suggestions -> [". Did you mean:\n\n" | Enum.map(suggestions, &format_fa/1)]
|
|
end
|
|
end
|
|
|
|
defp format_fa({_dist, fun, arity}) do
|
|
[" * ", Macro.inspect_atom(:remote_call, fun), ?/, Integer.to_string(arity), ?\n]
|
|
end
|
|
|
|
defp exports_for(module) do
|
|
if function_exported?(module, :__info__, 1) do
|
|
module.__info__(:macros) ++ module.__info__(:functions)
|
|
else
|
|
module.module_info(:exports)
|
|
end
|
|
rescue
|
|
# In case the module was removed while we are computing this
|
|
UndefinedFunctionError -> []
|
|
end
|
|
|
|
defp deprecated_functions_for(module) do
|
|
if function_exported?(module, :__info__, 1) do
|
|
for {name_arity, _message} <- module.__info__(:deprecated), do: name_arity
|
|
else
|
|
[]
|
|
end
|
|
rescue
|
|
# In case the module was removed while we are computing this
|
|
UndefinedFunctionError -> []
|
|
end
|
|
end
|
|
|
|
defmodule FunctionClauseError do
|
|
@moduledoc """
|
|
An exception raised when a function call doesn't match any defined clause.
|
|
|
|
For example:
|
|
|
|
iex> List.duplicate(:ok, -3)
|
|
** (FunctionClauseError) no function clause matching in List.duplicate/2
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:module` (`t:module/0`) - the module name
|
|
* `:function` (`t:atom/0`) - the function name
|
|
* `:arity` (`t:non_neg_integer/0`) - the arity of the function
|
|
"""
|
|
|
|
defexception [:module, :function, :arity, :kind, :args, :clauses]
|
|
|
|
@clause_limit 10
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
case exception do
|
|
%{function: nil} ->
|
|
"no function clause matches"
|
|
|
|
%{module: module, function: function, arity: arity} ->
|
|
formatted = Exception.format_mfa(module, function, arity)
|
|
blamed = blame(exception, &inspect/1, &blame_match/1)
|
|
"no function clause matching in #{formatted}" <> blamed
|
|
end
|
|
end
|
|
|
|
@impl true
|
|
def blame(%{module: module, function: function, arity: arity} = exception, stacktrace) do
|
|
case stacktrace do
|
|
[{^module, ^function, args, meta} | rest] when length(args) == arity ->
|
|
exception =
|
|
case Exception.blame_mfa(module, function, args) do
|
|
{:ok, kind, clauses} -> %{exception | args: args, kind: kind, clauses: clauses}
|
|
:error -> %{exception | args: args}
|
|
end
|
|
|
|
{exception, [{module, function, arity, meta} | rest]}
|
|
|
|
stacktrace ->
|
|
{exception, stacktrace}
|
|
end
|
|
end
|
|
|
|
defp blame_match(%{match?: true, node: node}), do: Macro.to_string(node)
|
|
defp blame_match(%{match?: false, node: node}), do: "-" <> Macro.to_string(node) <> "-"
|
|
|
|
@doc false
|
|
def blame(%{args: nil}, _, _) do
|
|
""
|
|
end
|
|
|
|
def blame(exception, inspect_fun, fun) do
|
|
%{module: module, function: function, arity: arity, kind: kind, args: args, clauses: clauses} =
|
|
exception
|
|
|
|
mfa = Exception.format_mfa(module, function, arity)
|
|
|
|
format_clause_fun = fn {args, guards} ->
|
|
args = Enum.map_join(args, ", ", fun)
|
|
base = " #{kind} #{function}(#{args})"
|
|
Enum.reduce(guards, base, &"#{&2} when #{clause_to_string(&1, fun, 0)}") <> "\n"
|
|
end
|
|
|
|
"\n\nThe following arguments were given to #{mfa}:\n" <>
|
|
"#{format_args(args, inspect_fun)}" <>
|
|
"#{format_clauses(clauses, format_clause_fun, @clause_limit)}"
|
|
end
|
|
|
|
defp clause_to_string({op, _, [left, right]} = node, fun, parent) do
|
|
case Code.Identifier.binary_op(op) do
|
|
{_side, precedence} ->
|
|
left = clause_to_string(left, fun, precedence)
|
|
right = clause_to_string(right, fun, precedence)
|
|
|
|
if parent > precedence do
|
|
"(" <> left <> " #{op} " <> right <> ")"
|
|
else
|
|
left <> " #{op} " <> right
|
|
end
|
|
|
|
_ ->
|
|
fun.(node)
|
|
end
|
|
end
|
|
|
|
defp clause_to_string(node, fun, _precedence), do: fun.(node)
|
|
|
|
defp format_args(args, inspect_fun) do
|
|
args
|
|
|> Enum.with_index(1)
|
|
|> Enum.map(fn {arg, i} ->
|
|
[pad("\n# "), Integer.to_string(i), pad("\n"), pad(inspect_fun.(arg)), "\n"]
|
|
end)
|
|
end
|
|
|
|
defp format_clauses(clauses, format_clause_fun, limit)
|
|
defp format_clauses(nil, _, _), do: ""
|
|
defp format_clauses([], _, _), do: ""
|
|
|
|
defp format_clauses(clauses, format_clause_fun, limit) do
|
|
top_clauses =
|
|
clauses
|
|
|> Enum.take(limit)
|
|
|> Enum.map(format_clause_fun)
|
|
|
|
[
|
|
"\nAttempted function clauses (showing #{length(top_clauses)} out of #{length(clauses)}):",
|
|
"\n\n",
|
|
top_clauses,
|
|
non_visible_clauses(length(clauses) - limit)
|
|
]
|
|
end
|
|
|
|
defp non_visible_clauses(n) when n <= 0, do: []
|
|
defp non_visible_clauses(1), do: [" ...\n (1 clause not shown)\n"]
|
|
defp non_visible_clauses(n), do: [" ...\n (#{n} clauses not shown)\n"]
|
|
|
|
defp pad(string) do
|
|
String.replace(string, "\n", "\n ")
|
|
end
|
|
end
|
|
|
|
defmodule Code.LoadError do
|
|
@moduledoc """
|
|
An exception raised when a file cannot be loaded.
|
|
|
|
This is typically raised by functions in the `Code` module, for example:
|
|
|
|
Code.require_file("missing_file.exs")
|
|
** (Code.LoadError) could not load missing_file.exs. Reason: enoent
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:file` (`t:String.t/0`) - the file name
|
|
* `:reason` (`t:term/0`) - the reason why the file could not be loaded
|
|
"""
|
|
|
|
defexception [:file, :message, :reason]
|
|
|
|
def exception(opts) do
|
|
file = Keyword.fetch!(opts, :file)
|
|
reason = Keyword.fetch!(opts, :reason)
|
|
message = "could not load #{file}. Reason: #{reason}"
|
|
%Code.LoadError{message: message, file: file, reason: reason}
|
|
end
|
|
end
|
|
|
|
defmodule Protocol.UndefinedError do
|
|
@moduledoc """
|
|
An exception raised when a protocol is not implemented for a given value.
|
|
|
|
For example:
|
|
|
|
iex> Enum.at("A string!", 0)
|
|
** (Protocol.UndefinedError) protocol Enumerable not implemented for BitString
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:protocol` (`t:module/0`) - the protocol that is not implemented
|
|
* `:value` (`t:term/0`) - the value that does not implement the protocol
|
|
"""
|
|
|
|
defexception [:protocol, :value, description: ""]
|
|
|
|
@impl true
|
|
def message(%{protocol: protocol, value: value, description: description}) do
|
|
inspected =
|
|
value
|
|
|> inspect(pretty: true)
|
|
# Indent only lines with contents on them
|
|
|> String.replace(~r/^(?=.+)/m, " ")
|
|
|
|
"protocol #{inspect(protocol)} not implemented for " <>
|
|
value_type(value) <>
|
|
maybe_description(description) <>
|
|
maybe_available(protocol) <>
|
|
"""
|
|
|
|
|
|
Got value:
|
|
|
|
#{inspected}
|
|
"""
|
|
end
|
|
|
|
defp value_type(%{__struct__: struct}), do: "#{inspect(struct)} (a struct)"
|
|
defp value_type(value) when is_atom(value), do: "Atom"
|
|
defp value_type(value) when is_bitstring(value), do: "BitString"
|
|
defp value_type(value) when is_float(value), do: "Float"
|
|
defp value_type(value) when is_function(value), do: "Function"
|
|
defp value_type(value) when is_integer(value), do: "Integer"
|
|
defp value_type(value) when is_list(value), do: "List"
|
|
defp value_type(value) when is_map(value), do: "Map"
|
|
defp value_type(value) when is_pid(value), do: "PID"
|
|
defp value_type(value) when is_port(value), do: "Port"
|
|
defp value_type(value) when is_reference(value), do: "Reference"
|
|
defp value_type(value) when is_tuple(value), do: "Tuple"
|
|
|
|
defp maybe_description(""), do: ""
|
|
defp maybe_description(description), do: ", " <> description
|
|
|
|
defp maybe_available(protocol) do
|
|
case protocol.__protocol__(:impls) do
|
|
{:consolidated, []} ->
|
|
". There are no implementations for this protocol."
|
|
|
|
{:consolidated, types} ->
|
|
". This protocol is implemented for: " <>
|
|
Enum.map_join(types, ", ", &inspect/1)
|
|
|
|
:not_consolidated ->
|
|
""
|
|
end
|
|
end
|
|
end
|
|
|
|
defmodule KeyError do
|
|
@moduledoc """
|
|
An exception raised when a key is not found in a data structure.
|
|
|
|
For example, this is raised by `Map.fetch!/2` when the given key
|
|
cannot be found in the given map:
|
|
|
|
iex> map = %{name: "Alice", age: 25}
|
|
iex> Map.fetch!(map, :first_name)
|
|
** (KeyError) key :first_name not found in:
|
|
...
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:term` (`t:term/0`) - the data structure that was searched
|
|
* `:key` (`t:term/0`) - the key that was not found
|
|
"""
|
|
|
|
defexception [:key, :term, :message]
|
|
|
|
@impl true
|
|
def message(exception = %{message: nil}), do: message(exception.key, exception.term)
|
|
def message(%{message: message}), do: message
|
|
|
|
defp message(key, term) do
|
|
message = "key #{inspect(key)} not found"
|
|
|
|
cond do
|
|
term == nil ->
|
|
message
|
|
|
|
is_atom(term) and is_atom(key) ->
|
|
message <>
|
|
" in: #{inspect(term)} (if instead you want to invoke #{inspect(term)}.#{key}(), " <>
|
|
"make sure to add parentheses after the function name)"
|
|
|
|
true ->
|
|
Exception.__format_message_with_term__(
|
|
message <> " in:",
|
|
term
|
|
)
|
|
end
|
|
end
|
|
|
|
@impl true
|
|
def blame(exception = %{message: message}, stacktrace) when is_binary(message) do
|
|
{exception, stacktrace}
|
|
end
|
|
|
|
def blame(exception, stacktrace) do
|
|
%{term: term, key: key} = exception
|
|
message = message(key, term)
|
|
|
|
if is_atom(key) and (map_with_atom_keys_only?(term) or Keyword.keyword?(term)) do
|
|
hint = did_you_mean(key, available_keys(term))
|
|
message = message <> IO.iodata_to_binary(hint)
|
|
{%{exception | message: message}, stacktrace}
|
|
else
|
|
{%{exception | message: message}, stacktrace}
|
|
end
|
|
end
|
|
|
|
defp map_with_atom_keys_only?(term) do
|
|
is_map(term) and Enum.all?(Map.to_list(term), fn {k, _} -> is_atom(k) end)
|
|
end
|
|
|
|
defp available_keys(term) when is_map(term), do: Map.keys(term)
|
|
defp available_keys(term) when is_list(term), do: Keyword.keys(term)
|
|
|
|
@threshold 0.77
|
|
@max_suggestions 5
|
|
defp did_you_mean(missing_key, available_keys) do
|
|
stringified_key = Atom.to_string(missing_key)
|
|
|
|
suggestions =
|
|
for key <- available_keys,
|
|
distance = String.jaro_distance(stringified_key, Atom.to_string(key)),
|
|
distance >= @threshold,
|
|
do: {distance, key}
|
|
|
|
case suggestions do
|
|
[] -> []
|
|
suggestions -> ["\nDid you mean:\n\n" | format_suggestions(suggestions)]
|
|
end
|
|
end
|
|
|
|
defp format_suggestions(suggestions) do
|
|
suggestions
|
|
|> Enum.sort(&(elem(&1, 0) >= elem(&2, 0)))
|
|
|> Enum.take(@max_suggestions)
|
|
|> Enum.sort(&(elem(&1, 1) <= elem(&2, 1)))
|
|
|> Enum.map(fn {_, key} -> [" * ", inspect(key), ?\n] end)
|
|
end
|
|
end
|
|
|
|
defmodule UnicodeConversionError do
|
|
@moduledoc """
|
|
An exception raised when converting data to or from Unicode.
|
|
|
|
For example:
|
|
|
|
iex> String.to_charlist(<<0xFF>>)
|
|
** (UnicodeConversionError) invalid encoding starting at <<255>>
|
|
|
|
"""
|
|
defexception [:encoded, :message]
|
|
|
|
def exception(opts) do
|
|
%UnicodeConversionError{
|
|
encoded: Keyword.fetch!(opts, :encoded),
|
|
message: "#{Keyword.fetch!(opts, :kind)} #{detail(Keyword.fetch!(opts, :rest))}"
|
|
}
|
|
end
|
|
|
|
defp detail(rest) when is_binary(rest) do
|
|
"encoding starting at #{inspect(rest)}"
|
|
end
|
|
|
|
defp detail([h | _]) when is_integer(h) do
|
|
"code point #{h}"
|
|
end
|
|
|
|
defp detail([h | _]) do
|
|
detail(h)
|
|
end
|
|
end
|
|
|
|
defmodule MissingApplicationsError do
|
|
@moduledoc """
|
|
An exception that is raised when an application depends on one or more
|
|
missing applications.
|
|
|
|
This exception is used by Mix and other tools. It can also be used by library authors
|
|
when their library only requires an external application (like a dependency) for a subset
|
|
of features.
|
|
|
|
The fields of this exception are public. See `t:t/0`.
|
|
|
|
*Available since v1.18.0.*
|
|
|
|
## Examples
|
|
|
|
unless Application.spec(:plug, :vsn) do
|
|
raise MissingApplicationsError,
|
|
description: "application :plug is required for testing Plug-related functionality",
|
|
apps: [{:plug, "~> 1.0"}]
|
|
end
|
|
|
|
"""
|
|
|
|
@moduledoc since: "1.18.0"
|
|
|
|
@type t() :: %__MODULE__{
|
|
apps: [{Application.app(), Version.requirement()}, ...],
|
|
description: String.t()
|
|
}
|
|
|
|
defexception apps: [], description: "missing applications found"
|
|
|
|
@impl true
|
|
def message(%__MODULE__{apps: apps, description: description}) do
|
|
# We explicitly format these as tuples so that they're easier to copy-paste
|
|
# into dependencies.
|
|
formatted_apps =
|
|
Enum.map(apps, fn {app_name, requirement} ->
|
|
~s(\n {#{inspect(app_name)}, "#{requirement}"})
|
|
end)
|
|
|
|
"""
|
|
#{description}
|
|
|
|
To address this, include these applications as your dependencies:
|
|
#{formatted_apps}\
|
|
"""
|
|
end
|
|
end
|
|
|
|
defmodule Enum.OutOfBoundsError do
|
|
@moduledoc """
|
|
An exception that is raised when a function expects an enumerable to have
|
|
a certain size but finds that it is too small.
|
|
|
|
For example:
|
|
|
|
iex> Enum.fetch!([1, 2, 3], 5)
|
|
** (Enum.OutOfBoundsError) out of bounds error at position 5 when traversing enumerable [1, 2, 3]
|
|
"""
|
|
|
|
defexception [:enumerable, :index, :message]
|
|
|
|
@impl true
|
|
def message(exception = %{message: nil}), do: message(exception.index, exception.enumerable)
|
|
def message(%{message: message}), do: message
|
|
|
|
def message(index, enumerable) do
|
|
"out of bounds error" <>
|
|
if index do
|
|
" at position #{index}"
|
|
else
|
|
""
|
|
end <>
|
|
if enumerable do
|
|
" when traversing enumerable #{inspect(enumerable)}"
|
|
else
|
|
""
|
|
end
|
|
end
|
|
end
|
|
|
|
defmodule Enum.EmptyError do
|
|
@moduledoc """
|
|
An exception that is raised when something expects a non-empty enumerable
|
|
but finds an empty one.
|
|
|
|
For example:
|
|
|
|
iex> Enum.min([])
|
|
** (Enum.EmptyError) empty error
|
|
|
|
"""
|
|
|
|
defexception message: "empty error"
|
|
end
|
|
|
|
defmodule File.Error do
|
|
@moduledoc """
|
|
An exception that is raised when a file operation fails.
|
|
|
|
For example, this exception is raised, when trying to read a non existent file:
|
|
|
|
iex> File.read!("nonexistent_file.txt")
|
|
** (File.Error) could not read file "nonexistent_file.txt": no such file or directory
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:path` (`t:Path.t/0`) - the path of the file that caused the error
|
|
* `:reason` (`t:File.posix/0`) - the reason for the error
|
|
|
|
"""
|
|
|
|
defexception [:reason, :path, action: ""]
|
|
|
|
@impl true
|
|
def message(%{action: action, reason: reason, path: path}) do
|
|
formatted =
|
|
case {action, reason} do
|
|
{"remove directory", :eexist} ->
|
|
"directory is not empty"
|
|
|
|
_ ->
|
|
IO.iodata_to_binary(:file.format_error(reason))
|
|
end
|
|
|
|
"could not #{action} #{inspect(path)}: #{formatted}"
|
|
end
|
|
end
|
|
|
|
defmodule File.CopyError do
|
|
@moduledoc """
|
|
An exception that is raised when copying a file fails.
|
|
|
|
For example, this exception is raised when trying to copy to file or directory that isn't present:
|
|
|
|
iex> File.cp_r!("non_existent", "source_dir/subdir")
|
|
** (File.CopyError) could not copy recursively from "non_existent" to "source_dir/subdir". non_existent: no such file or directory
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:source` (`t:Path.t/0`) - the source path
|
|
* `:destination` (`t:Path.t/0`) - the destination path
|
|
* `:reason` (`t:File.posix/0`) - the reason why the file could not be copied
|
|
|
|
"""
|
|
|
|
defexception [:reason, :source, :destination, on: "", action: ""]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
formatted = IO.iodata_to_binary(:file.format_error(exception.reason))
|
|
|
|
location =
|
|
case exception.on do
|
|
"" -> ""
|
|
on -> ". #{on}"
|
|
end
|
|
|
|
"could not #{exception.action} from #{inspect(exception.source)} to " <>
|
|
"#{inspect(exception.destination)}#{location}: #{formatted}"
|
|
end
|
|
end
|
|
|
|
defmodule File.RenameError do
|
|
@moduledoc """
|
|
An exception that is raised when renaming a file fails.
|
|
|
|
For example, this exception is raised when trying to rename a file that isn't present:
|
|
|
|
iex> File.rename!("source.txt", "target.txt")
|
|
** (File.RenameError) could not rename from "source.txt" to "target.txt": no such file or directory
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:source` (`t:Path.t/0`) - the source path
|
|
* `:destination` (`t:Path.t/0`) - the destination path
|
|
* `:reason` (`t:File.posix/0`) - the reason why the file could not be renamed
|
|
|
|
"""
|
|
|
|
defexception [:reason, :source, :destination, on: "", action: ""]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
formatted = IO.iodata_to_binary(:file.format_error(exception.reason))
|
|
|
|
location =
|
|
case exception.on do
|
|
"" -> ""
|
|
on -> ". #{on}"
|
|
end
|
|
|
|
"could not #{exception.action} from #{inspect(exception.source)} to " <>
|
|
"#{inspect(exception.destination)}#{location}: #{formatted}"
|
|
end
|
|
end
|
|
|
|
defmodule File.LinkError do
|
|
@moduledoc """
|
|
An exception that is raised when linking a file fails.
|
|
|
|
For example, this exception is raised when trying to link to file that isn't present:
|
|
|
|
iex> File.ln!("existing.txt", "link.txt")
|
|
** (File.LinkError) could not create hard link from "link.txt" to "existing.txt": no such file or directory
|
|
|
|
The following fields of this exception are public and can be accessed freely:
|
|
|
|
* `:existing` (`t:Path.t/0`) - the existing file to link
|
|
* `:new` (`t:Path.t/0`) - the link destination
|
|
* `:reason` (`t:File.posix/0`) - the reason why the file could not be linked
|
|
|
|
"""
|
|
|
|
defexception [:reason, :existing, :new, action: ""]
|
|
|
|
@impl true
|
|
def message(exception) do
|
|
formatted = IO.iodata_to_binary(:file.format_error(exception.reason))
|
|
|
|
"could not #{exception.action} from #{inspect(exception.new)} to " <>
|
|
"#{inspect(exception.existing)}: #{formatted}"
|
|
end
|
|
end
|
|
|
|
defmodule ErlangError do
|
|
@moduledoc """
|
|
An exception raised when invoking an Erlang code that errors
|
|
with a value not handled by Elixir.
|
|
|
|
Most common error reasons, such as `:badarg` are automatically
|
|
converted into exceptions by Elixir. However, you may invoke some
|
|
code that emits a custom error reason and those get wrapped into
|
|
`ErlangError`:
|
|
|
|
iex> :erlang.error(:some_invalid_error)
|
|
** (ErlangError) Erlang error: :some_invalid_error
|
|
"""
|
|
|
|
defexception [:original, :reason]
|
|
|
|
@impl true
|
|
def message(exception)
|
|
|
|
def message(%__MODULE__{original: original, reason: nil}) do
|
|
"Erlang error: #{inspect(original)}"
|
|
end
|
|
|
|
def message(%__MODULE__{original: original, reason: reason}) do
|
|
IO.iodata_to_binary(["Erlang error: ", inspect(original), reason])
|
|
end
|
|
|
|
@doc false
|
|
def normalize(:badarg, stacktrace) do
|
|
case stacktrace do
|
|
[{:erlang, :apply, [module, function, args], _} | _] when not is_atom(module) ->
|
|
message =
|
|
cond do
|
|
is_map(module) and is_atom(function) and is_map_key(module, function) ->
|
|
"you attempted to apply a function named #{inspect(function)} on a map/struct. " <>
|
|
"If you are using Kernel.apply/3, make sure the module is an atom. " <>
|
|
if is_function(Map.get(module, function)) do
|
|
"If you are trying to invoke an anonymous function in a map/struct, " <>
|
|
"add a dot between the function name and the parenthesis: map.#{function}.()"
|
|
else
|
|
"If you are using the dot syntax, ensure there are no parentheses " <>
|
|
"after the field name, such as map.#{function}"
|
|
end
|
|
|
|
is_atom(function) and args == [] ->
|
|
"you attempted to apply a function named #{inspect(function)} on #{inspect(module)}. " <>
|
|
"If you are using Kernel.apply/3, make sure the module is an atom. " <>
|
|
"If you are using the dot syntax, such as module.function(), " <>
|
|
"make sure the left-hand side of the dot is an atom representing a module"
|
|
|
|
true ->
|
|
"you attempted to apply a function on #{inspect(module)}. " <>
|
|
"Modules (the first argument of apply) must always be an atom"
|
|
end
|
|
|
|
%ArgumentError{message: message}
|
|
|
|
_ ->
|
|
case error_info(:badarg, stacktrace, "errors were found at the given arguments") do
|
|
{:ok, reason, details} -> %ArgumentError{message: reason <> details}
|
|
:error -> %ArgumentError{}
|
|
end
|
|
end
|
|
end
|
|
|
|
def normalize(:badarith, _stacktrace) do
|
|
%ArithmeticError{}
|
|
end
|
|
|
|
def normalize(:system_limit, stacktrace) do
|
|
default_reason = "a system limit has been reached due to errors at the given arguments"
|
|
|
|
case error_info(:system_limit, stacktrace, default_reason) do
|
|
{:ok, reason, details} -> %SystemLimitError{message: reason <> details}
|
|
:error -> %SystemLimitError{}
|
|
end
|
|
end
|
|
|
|
def normalize(:cond_clause, _stacktrace) do
|
|
%CondClauseError{}
|
|
end
|
|
|
|
def normalize({:badarity, {fun, args}}, _stacktrace) do
|
|
%BadArityError{function: fun, args: args}
|
|
end
|
|
|
|
def normalize({:badfun, term}, _stacktrace) do
|
|
%BadFunctionError{term: term}
|
|
end
|
|
|
|
def normalize({:badmatch, term}, _stacktrace) do
|
|
%MatchError{term: term}
|
|
end
|
|
|
|
def normalize({:badmap, term}, _stacktrace) do
|
|
%BadMapError{term: term}
|
|
end
|
|
|
|
def normalize({:badbool, op, term}, _stacktrace) do
|
|
%BadBooleanError{operator: op, term: term}
|
|
end
|
|
|
|
def normalize({:badkey, key}, stacktrace) do
|
|
term =
|
|
case stacktrace do
|
|
[{Map, :get_and_update!, [map, _, _], _} | _] -> map
|
|
[{Map, :update!, [map, _, _], _} | _] -> map
|
|
[{:maps, :update, [_, _, map], _} | _] -> map
|
|
[{:maps, :get, [_, map], _} | _] -> map
|
|
[{:erlang, :map_get, [_, map], _} | _] -> map
|
|
_ -> nil
|
|
end
|
|
|
|
%KeyError{key: key, term: term}
|
|
end
|
|
|
|
def normalize({:badkey, key, map}, _stacktrace) when is_map(map) do
|
|
%KeyError{key: key, term: map}
|
|
end
|
|
|
|
def normalize({:badkey, key, term}, _stacktrace) do
|
|
message =
|
|
"key #{inspect(key)} not found in: #{inspect(term, pretty: true, limit: :infinity)}\n\n" <>
|
|
"If you are using the dot syntax, such as map.field, " <>
|
|
"make sure the left-hand side of the dot is a map"
|
|
|
|
%KeyError{key: key, term: term, message: message}
|
|
end
|
|
|
|
def normalize({:case_clause, term}, _stacktrace) do
|
|
%CaseClauseError{term: term}
|
|
end
|
|
|
|
# :else_clause is aligned on what Erlang returns for `maybe`
|
|
def normalize({:else_clause, term}, _stacktrace) do
|
|
%WithClauseError{term: term}
|
|
end
|
|
|
|
def normalize({:try_clause, term}, _stacktrace) do
|
|
%TryClauseError{term: term}
|
|
end
|
|
|
|
def normalize(:undef, stacktrace) do
|
|
{mod, fun, arity} = from_stacktrace(stacktrace)
|
|
%UndefinedFunctionError{module: mod, function: fun, arity: arity}
|
|
end
|
|
|
|
def normalize(:function_clause, stacktrace) do
|
|
{mod, fun, arity} = from_stacktrace(stacktrace)
|
|
%FunctionClauseError{module: mod, function: fun, arity: arity}
|
|
end
|
|
|
|
def normalize({:badarg, payload}, _stacktrace) do
|
|
%ArgumentError{message: "argument error: #{inspect(payload)}"}
|
|
end
|
|
|
|
def normalize(other, stacktrace) do
|
|
case error_info(other, stacktrace, "") do
|
|
{:ok, _reason, details} -> %ErlangError{original: other, reason: details}
|
|
:error -> %ErlangError{original: other}
|
|
end
|
|
end
|
|
|
|
defp from_stacktrace([{module, function, args, _} | _]) when is_list(args) do
|
|
{module, function, length(args)}
|
|
end
|
|
|
|
defp from_stacktrace([{module, function, arity, _} | _]) do
|
|
{module, function, arity}
|
|
end
|
|
|
|
defp from_stacktrace(_) do
|
|
{nil, nil, nil}
|
|
end
|
|
|
|
defp error_info(erl_exception, stacktrace, default_reason) do
|
|
with [{module, fun, args_or_arity, opts} | tail] <- stacktrace,
|
|
%{} = error_info <- opts[:error_info] do
|
|
error_module = Map.get(error_info, :module, module)
|
|
error_fun = Map.get(error_info, :function, :format_error)
|
|
|
|
error_info = Map.put(error_info, :pretty_printer, &inspect/1)
|
|
head = {module, fun, args_or_arity, Keyword.put(opts, :error_info, error_info)}
|
|
|
|
extra =
|
|
try do
|
|
apply(error_module, error_fun, [erl_exception, [head | tail]])
|
|
rescue
|
|
_ -> %{}
|
|
end
|
|
|
|
arity = if is_integer(args_or_arity), do: args_or_arity, else: length(args_or_arity)
|
|
args_errors = Map.take(extra, Enum.to_list(1..arity//1))
|
|
reason = Map.get(extra, :reason, default_reason)
|
|
|
|
cond do
|
|
map_size(args_errors) > 0 ->
|
|
{:ok, reason, IO.iodata_to_binary([":\n\n" | Enum.map(args_errors, &arg_error/1)])}
|
|
|
|
general = extra[:general] ->
|
|
{:ok, reason, ": " <> IO.chardata_to_string(general)}
|
|
|
|
true ->
|
|
:error
|
|
end
|
|
else
|
|
_ -> :error
|
|
end
|
|
end
|
|
|
|
defp arg_error({n, message}), do: " * #{nth(n)} argument: #{message}\n"
|
|
|
|
defp nth(1), do: "1st"
|
|
defp nth(2), do: "2nd"
|
|
defp nth(3), do: "3rd"
|
|
defp nth(n), do: "#{n}th"
|
|
end
|