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+;;; test-custom-misc-count-words.el --- Tests for cj/--count-words -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for the cj/--count-words function from custom-misc.el
+;;
+;; This function counts words in a region using Emacs's built-in count-words.
+;; A word is defined by Emacs's word boundaries, which generally means
+;; sequences of word-constituent characters separated by whitespace or punctuation.
+;;
+;; We test the NON-INTERACTIVE implementation (cj/--count-words) to avoid
+;; mocking region selection. This follows our testing best practice of
+;; separating business logic from UI interaction.
+
+;;; Code:
+
+(require 'ert)
+(require 'testutil-general)
+
+;; Add modules directory to load path
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+
+;; Stub dependencies before loading the module
+(defvar cj/custom-keymap (make-sparse-keymap)
+  "Stub keymap for testing.")
+
+;; Now load the actual production module
+(require 'custom-misc)
+
+;;; Test Helpers
+
+(defun test-count-words (input-text)
+  "Test cj/--count-words on INPUT-TEXT.
+Returns the word count."
+  (with-temp-buffer
+    (insert input-text)
+    (cj/--count-words (point-min) (point-max))))
+
+;;; Normal Cases
+
+(ert-deftest test-count-words-multiple-words ()
+  "Should count multiple words."
+  (should (= 5 (test-count-words "The quick brown fox jumps"))))
+
+(ert-deftest test-count-words-single-word ()
+  "Should count single word."
+  (should (= 1 (test-count-words "hello"))))
+
+(ert-deftest test-count-words-with-punctuation ()
+  "Should count words with punctuation."
+  (should (= 5 (test-count-words "Hello, world! How are you?"))))
+
+(ert-deftest test-count-words-multiple-spaces ()
+  "Should count words separated by multiple spaces."
+  (should (= 3 (test-count-words "hello    world    test"))))
+
+(ert-deftest test-count-words-with-newlines ()
+  "Should count words across newlines."
+  (should (= 6 (test-count-words "line one\nline two\nline three"))))
+
+(ert-deftest test-count-words-with-tabs ()
+  "Should count words separated by tabs."
+  (should (= 3 (test-count-words "hello\tworld\ttest"))))
+
+(ert-deftest test-count-words-mixed-whitespace ()
+  "Should count words with mixed whitespace."
+  (should (= 4 (test-count-words "hello \t world\n\ntest  end"))))
+
+(ert-deftest test-count-words-hyphenated ()
+  "Should count hyphenated words."
+  ;; Emacs treats hyphens as word separators in count-words
+  (should (= 7 (test-count-words "This is state-of-the-art technology"))))
+
+(ert-deftest test-count-words-contractions ()
+  "Should count contractions."
+  ;; Emacs treats apostrophes as word separators in count-words
+  (should (= 6 (test-count-words "don't can't won't"))))
+
+(ert-deftest test-count-words-numbers ()
+  "Should count numbers as words."
+  (should (= 6 (test-count-words "The year 2024 has 365 days"))))
+
+;;; Boundary Cases
+
+(ert-deftest test-count-words-empty-string ()
+  "Should return 0 for empty string."
+  (should (= 0 (test-count-words ""))))
+
+(ert-deftest test-count-words-only-whitespace ()
+  "Should return 0 for whitespace-only text."
+  (should (= 0 (test-count-words "   \t\n\n   "))))
+
+(ert-deftest test-count-words-only-punctuation ()
+  "Should count punctuation-only text."
+  ;; Emacs may count consecutive punctuation as a word
+  (should (= 1 (test-count-words "!@#$%^&*()"))))
+
+(ert-deftest test-count-words-leading-trailing-spaces ()
+  "Should count words ignoring leading/trailing spaces."
+  (should (= 3 (test-count-words "   hello world test   "))))
+
+(ert-deftest test-count-words-unicode ()
+  "Should count Unicode words."
+  (should (= 3 (test-count-words "café résumé naïve"))))
+
+(ert-deftest test-count-words-very-long-text ()
+  "Should handle very long text."
+  (let ((long-text (mapconcat (lambda (_) "word") (make-list 1000 nil) " ")))
+    (should (= 1000 (test-count-words long-text)))))
+
+(ert-deftest test-count-words-multiline-paragraph ()
+  "Should count words in multi-line paragraph."
+  (let ((text "This is a paragraph
+that spans multiple
+lines with various
+words in it."))
+    (should (= 13 (test-count-words text)))))
+
+;;; Error Cases
+
+(ert-deftest test-count-words-start-greater-than-end ()
+  "Should error when start > end."
+  (should-error
+   (with-temp-buffer
+     (insert "hello world")
+     (cj/--count-words (point-max) (point-min)))
+   :type 'error))
+
+(ert-deftest test-count-words-empty-region ()
+  "Should return 0 for empty region (start == end)."
+  (with-temp-buffer
+    (insert "hello world")
+    (let ((pos (/ (+ (point-min) (point-max)) 2)))
+      (should (= 0 (cj/--count-words pos pos))))))
+
+(ert-deftest test-count-words-partial-region ()
+  "Should count words only in specified region."
+  (with-temp-buffer
+    (insert "one two three four five")
+    ;; Count only "two three four" (positions roughly in middle)
+    (goto-char (point-min))
+    (search-forward "two")
+    (let ((start (match-beginning 0)))
+      (search-forward "four")
+      (let ((end (match-end 0)))
+        (should (= 3 (cj/--count-words start end)))))))
+
+(provide 'test-custom-misc-count-words)
+;;; test-custom-misc-count-words.el ends here