From 206ed0e9d273d8f24c4b09898c0cffd2c5cd4cbc Mon Sep 17 00:00:00 2001
From: Luis Eduardo Bueso de Barrio <luiseduardobueso96@gmail.com>
Date: Sat, 24 Jan 2026 17:28:00 +0100
Subject: [PATCH] 02-basic-execution.md done

---
 ob-elixir.el           | 88 ++++++++++++++++++++++++++++++++++++++++++
 test/test-ob-elixir.el | 36 +++++++++++++++++
 2 files changed, 124 insertions(+)

diff --git a/ob-elixir.el b/ob-elixir.el
index 9343c4f..23fdc5e 100644
--- a/ob-elixir.el
+++ b/ob-elixir.el
@@ -37,5 +37,93 @@
 (require 'ob)
 (require 'ob-eval)
 
+;;; Customization
+
+(defgroup ob-elixir nil
+  "Org Babel support for Elixir."
+  :group 'org-babel
+  :prefix "ob-elixir-")
+
+(defcustom ob-elixir-command "elixir"
+  "Command to execute Elixir code.
+Can be a full path or command name if in PATH."
+  :type 'string
+  :group 'ob-elixir
+  :safe #'stringp)
+
+;;; Header Arguments
+
+(defvar org-babel-default-header-args:elixir
+  '((:results . "value")
+    (:session . "none"))
+  "Default header arguments for Elixir code blocks.")
+
+;;; Language Registration
+
+;; File extension for tangling
+(add-to-list 'org-babel-tangle-lang-exts '("elixir" . "ex"))
+
+;; Associate with elixir-mode for syntax highlighting (if available)
+(with-eval-after-load 'org-src
+  (add-to-list 'org-src-lang-modes '("elixir" . elixir)))
+
+;;; Execution
+
+(defconst ob-elixir--value-wrapper
+  "result = (
+%s
+)
+IO.puts(inspect(result, limit: :infinity, printable_limit: :infinity, charlists: :as_lists))
+"
+  "Wrapper template for capturing Elixir expression value.
+%s is replaced with the user's code.")
+
+(defun ob-elixir--wrap-for-value (body)
+  "Wrap BODY to capture its return value.
+
+The wrapper evaluates BODY, then prints the result using
+`inspect/2` with infinite limits to avoid truncation."
+  (format ob-elixir--value-wrapper body))
+
+(defun ob-elixir--execute (body result-type)
+  "Execute BODY as Elixir code.
+
+RESULT-TYPE is either `value' or `output'.
+For `value', wraps code to capture return value.
+For `output', captures stdout directly.
+
+Returns the result as a string."
+  (let* ((tmp-file (org-babel-temp-file "ob-elixir-" ".exs"))
+         (code (if (eq result-type 'value)
+                   (ob-elixir--wrap-for-value body)
+                 body)))
+    (with-temp-file tmp-file
+      (insert code))
+    (let ((result (org-babel-eval
+                   (format "%s %s"
+                           ob-elixir-command
+                           (org-babel-process-file-name tmp-file))
+                   "")))
+      (string-trim result))))
+
+(defun org-babel-execute:elixir (body params)
+  "Execute a block of Elixir code with org-babel.
+
+BODY is the Elixir code to execute.
+PARAMS is an alist of header arguments.
+
+This function is called by `org-babel-execute-src-block'."
+  (let* ((result-type (cdr (assq :result-type params)))
+         (result-params (cdr (assq :result-params params)))
+         (result (ob-elixir--execute body result-type)))
+    (org-babel-reassemble-table
+     (org-babel-result-cond result-params
+       result
+       (org-babel-script-escape result))
+     (org-babel-pick-name (cdr (assq :colname-names params))
+                          (cdr (assq :colnames params)))
+     (org-babel-pick-name (cdr (assq :rowname-names params))
+                          (cdr (assq :rownames params))))))
+
 (provide 'ob-elixir)
 ;;; ob-elixir.el ends here
diff --git a/test/test-ob-elixir.el b/test/test-ob-elixir.el
index e9c2635..ca52467 100644
--- a/test/test-ob-elixir.el
+++ b/test/test-ob-elixir.el
@@ -18,5 +18,41 @@
   "Test that the package loads successfully."
   (should (featurep 'ob-elixir)))
 
+(ert-deftest ob-elixir-test-elixir-available ()
+  "Test that Elixir is available."
+  (should (executable-find ob-elixir-command)))
+
+(ert-deftest ob-elixir-test-simple-value ()
+  "Test simple value evaluation."
+  (skip-unless (executable-find ob-elixir-command))
+  (let ((result (ob-elixir--execute "1 + 1" 'value)))
+    (should (equal "2" result))))
+
+(ert-deftest ob-elixir-test-simple-output ()
+  "Test simple output evaluation."
+  (skip-unless (executable-find ob-elixir-command))
+  (let ((result (ob-elixir--execute "IO.puts(\"hello\")" 'output)))
+    (should (equal "hello" result))))
+
+(ert-deftest ob-elixir-test-multiline-value ()
+  "Test multiline code value evaluation."
+  (skip-unless (executable-find ob-elixir-command))
+  (let ((result (ob-elixir--execute "x = 10\ny = 20\nx + y" 'value)))
+    (should (equal "30" result))))
+
+(ert-deftest ob-elixir-test-list-result ()
+  "Test list result."
+  (skip-unless (executable-find ob-elixir-command))
+  (let ((result (ob-elixir--execute "[1, 2, 3]" 'value)))
+    (should (equal "[1, 2, 3]" result))))
+
+(ert-deftest ob-elixir-test-map-result ()
+  "Test map result."
+  (skip-unless (executable-find ob-elixir-command))
+  (let ((result (ob-elixir--execute "%{a: 1, b: 2}" 'value)))
+    ;; Maps are unordered in Elixir, so accept either order
+    (should (or (string-match-p "%{a: 1, b: 2}" result)
+                (string-match-p "%{b: 2, a: 1}" result)))))
+
 (provide 'test-ob-elixir)
 ;;; test-ob-elixir.el ends here