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+;;; clojure-ts-mode-config-test.el --- Clojure TS Mode: configuration test suite  -*- lexical-binding: t; -*-
+
+;; Copyright © 2025-2026 Bozhidar Batsov
+
+;; This file is not part of GNU Emacs.
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Tests for clojure-ts-mode configuration options (defcustom variables).
+
+;;; Code:
+
+(require 'clojure-ts-mode)
+(require 'buttercup)
+(require 'test-helper "test/test-helper")
+
+;;;; clojure-ts-toplevel-inside-comment-form
+
+(describe "clojure-ts-toplevel-inside-comment-form"
+  (before-all
+    (unless (treesit-language-available-p 'clojure)
+      (signal 'buttercup-pending "tree-sitter Clojure grammar not available")))
+
+  (it "should treat the comment form as a defun when nil (default)"
+    (with-clojure-ts-buffer "(comment\n  (defn foo [] 1)\n  (defn bar [] 2))"
+      ;; Point inside the comment form
+      (goto-char 15)
+      (let ((node (treesit-defun-at-point)))
+        ;; The defun-at-point should be the comment form
+        (expect node :not :to-be nil)
+        (expect (string-prefix-p "(comment" (treesit-node-text node))
+                :to-be-truthy))))
+
+  (it "should navigate to inner defns when non-nil"
+    (with-clojure-ts-buffer "(comment\n  (defn foo [] 1)\n  (defn bar [] 2))"
+      (setq-local clojure-ts-toplevel-inside-comment-form t)
+      ;; Point inside the comment form
+      (goto-char 15)
+      (let ((node (treesit-defun-at-point)))
+        ;; The defun-at-point should be the inner defn, not the comment
+        (expect node :not :to-be nil)
+        (expect (string-prefix-p "(defn foo" (treesit-node-text node))
+                :to-be-truthy)))))
+
+;;;; clojure-ts-docstring-fill-column
+
+(describe "clojure-ts-docstring-fill-column"
+  (it "should use the custom fill column when filling docstrings"
+    (with-clojure-ts-buffer "(defn foo
+  \"This is a short docstring.\"
+  [])"
+      (let ((clojure-ts-docstring-fill-column 20))
+        (goto-char (point-min))
+        (search-forward "This")
+        (fill-paragraph)
+        (expect (buffer-substring-no-properties (point-min) (point-max))
+                :to-equal "(defn foo
+  \"This is a short
+  docstring.\"
+  [])"))))
+
+  (it "should not affect comment filling"
+    (with-clojure-ts-buffer ";; This is a comment that should not be affected by the docstring fill column setting."
+      (let ((clojure-ts-docstring-fill-column 10)
+            (fill-column 70))
+        (goto-char (point-min))
+        (fill-paragraph)
+        ;; Comment wraps at fill-column (70), not docstring-fill-column (10)
+        (expect (buffer-substring-no-properties (point-min) (point-max))
+                :to-equal ";; This is a comment that should not be affected by the docstring fill
+;; column setting.")))))
+
+;;;; clojure-ts-docstring-fill-prefix-width
+
+(describe "clojure-ts-docstring-fill-prefix-width"
+  (it "should use custom fill prefix width when filling docstrings"
+    (with-clojure-ts-buffer "(defn foo
+  \"This is a short docstring.\"
+  [])"
+      (let ((clojure-ts-docstring-fill-column 20)
+            (clojure-ts-docstring-fill-prefix-width 4))
+        (goto-char (point-min))
+        (search-forward "This")
+        (fill-paragraph)
+        ;; Continuation lines should be indented with 4 spaces
+        (expect (buffer-substring-no-properties (point-min) (point-max))
+                :to-equal "(defn foo
+  \"This is a short
+    docstring.\"
+  [])"))))
+
+  (it "should default to 2 spaces for fill prefix"
+    (with-clojure-ts-buffer "(defn foo
+  \"This is a short docstring.\"
+  [])"
+      (let ((clojure-ts-docstring-fill-column 20))
+        (goto-char (point-min))
+        (search-forward "This")
+        (fill-paragraph)
+        ;; Default: continuation lines indented with 2 spaces
+        (expect (buffer-substring-no-properties (point-min) (point-max))
+                :to-equal "(defn foo
+  \"This is a short
+  docstring.\"
+  [])")))))
+
+;;;; clojure-ts-thread-all-but-last
+
+(describe "clojure-ts-thread-all-but-last"
+  (it "should thread all expressions by default"
+    (with-clojure-ts-buffer "(map inc (filter even? coll))"
+      (goto-char (point-min))
+      (clojure-ts-thread-last-all nil)
+      (expect (buffer-string)
+              :to-equal "(->> coll\n     (filter even?)\n     (map inc))")))
+
+  (it "should leave last expression unthreaded when set to t"
+    (with-clojure-ts-buffer "(map inc (filter even? coll))"
+      (let ((clojure-ts-thread-all-but-last t))
+        (goto-char (point-min))
+        (clojure-ts-thread-last-all nil))
+      (expect (buffer-string)
+              :to-equal "(->> (filter even? coll)\n     (map inc))")))
+
+  (it "should apply to thread-first-all as well"
+    (with-clojure-ts-buffer "(assoc (merge {} {:a 1}) :b 2)"
+      (let ((clojure-ts-thread-all-but-last t))
+        (goto-char (point-min))
+        (clojure-ts-thread-first-all nil))
+      (expect (buffer-string)
+              :to-equal "(-> (merge {} {:a 1})\n    (assoc :b 2))"))))
+
+;;; clojure-ts-mode-config-test.el ends here