test(ui-config): cover transparency apply/toggle and cursor-type setter

The previous test file covered only `cj/--buffer-cursor-state` and the cursor-color hook. `cj/apply-transparency`, `cj/toggle-transparency`, and `cj/set-cursor-type` were the gap. New tests stub the frame-mutating primitives so they run in batch and cover: alpha cons construction in both enabled and disabled states, the terminal-frame skip, the error-message path on `set-frame-parameter` failure, the toggle's flip + re-apply, double-toggle idempotence, and the cursor-type pass-through (including nil for invisible).

1 files changed, 126 insertions, 0 deletions

diff --git a/tests/test-ui-config-transparency-and-cursor.el b/tests/test-ui-config-transparency-and-cursor.el
new file mode 100644
index 00000000..b01fa2b7
--- /dev/null
+++ b/tests/test-ui-config-transparency-and-cursor.el
@@ -0,0 +1,126 @@
+;;; test-ui-config-transparency-and-cursor.el --- Tests for transparency + cursor-type helpers -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Companions to `test-ui-config--buffer-cursor-state.el'.  Covers the
+;; transparency apply/toggle pair and the cursor-type setter, which
+;; were untested before.  Frame-mutating primitives are stubbed so the
+;; tests run in batch without a graphical frame.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(setq load-prefer-newer t)
+(require 'ui-config)
+
+;;; cj/apply-transparency
+
+(ert-deftest test-ui-config-apply-transparency-enabled-uses-level-as-alpha ()
+  "Normal: when enabled, the alpha cons matches `cj/transparency-level'."
+  (let ((cj/enable-transparency t)
+        (cj/transparency-level 70)
+        (default-frame-alist nil)
+        (applied nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () t))
+              ((symbol-function 'set-frame-parameter)
+               (lambda (_frame param value)
+                 (when (eq param 'alpha) (setq applied value)))))
+      (cj/apply-transparency))
+    (should (equal applied '(70 . 70)))
+    (should (equal (alist-get 'alpha default-frame-alist) '(70 . 70)))))
+
+(ert-deftest test-ui-config-apply-transparency-disabled-uses-opaque ()
+  "Normal: when disabled, alpha resets to (100 . 100) (fully opaque)."
+  (let ((cj/enable-transparency nil)
+        (cj/transparency-level 50)
+        (default-frame-alist '((alpha . (50 . 50))))
+        (applied nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () t))
+              ((symbol-function 'set-frame-parameter)
+               (lambda (_frame param value)
+                 (when (eq param 'alpha) (setq applied value)))))
+      (cj/apply-transparency))
+    (should (equal applied '(100 . 100)))
+    (should (equal (alist-get 'alpha default-frame-alist) '(100 . 100)))))
+
+(ert-deftest test-ui-config-apply-transparency-skips-frame-call-on-terminal ()
+  "Boundary: on a terminal frame, skip `set-frame-parameter' but still update
+the default-frame-alist so a future graphical frame would pick it up."
+  (let ((cj/enable-transparency t)
+        (cj/transparency-level 60)
+        (default-frame-alist nil)
+        (set-called nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () nil))
+              ((symbol-function 'set-frame-parameter)
+               (lambda (&rest _) (setq set-called t))))
+      (cj/apply-transparency))
+    (should-not set-called)
+    (should (equal (alist-get 'alpha default-frame-alist) '(60 . 60)))))
+
+(ert-deftest test-ui-config-apply-transparency-error-message-on-failure ()
+  "Error: a `set-frame-parameter' error is captured by `condition-case' and
+surfaced via `message'; the default-alist update still happens."
+  (let ((cj/enable-transparency t)
+        (cj/transparency-level 60)
+        (default-frame-alist nil)
+        (msg nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () t))
+              ((symbol-function 'set-frame-parameter)
+               (lambda (&rest _) (error "boom")))
+              ((symbol-function 'message)
+               (lambda (fmt &rest args) (setq msg (apply #'format fmt args)))))
+      (cj/apply-transparency))
+    (should (string-match-p "Failed to set transparency" msg))
+    (should (equal (alist-get 'alpha default-frame-alist) '(60 . 60)))))
+
+;;; cj/toggle-transparency
+
+(ert-deftest test-ui-config-toggle-transparency-flips-and-applies ()
+  "Normal: `cj/toggle-transparency' flips `cj/enable-transparency' and re-applies."
+  (let ((cj/enable-transparency nil)
+        (cj/transparency-level 80)
+        (default-frame-alist nil)
+        (applied nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () t))
+              ((symbol-function 'set-frame-parameter)
+               (lambda (_frame param value)
+                 (when (eq param 'alpha) (setq applied value))))
+              ((symbol-function 'message) #'ignore))
+      (cj/toggle-transparency))
+    (should cj/enable-transparency)
+    (should (equal applied '(80 . 80)))))
+
+(ert-deftest test-ui-config-toggle-transparency-double-toggle-restores-state ()
+  "Boundary: two toggles in a row return `cj/enable-transparency' to its start."
+  (let ((cj/enable-transparency t)
+        (cj/transparency-level 90)
+        (default-frame-alist nil))
+    (cl-letf (((symbol-function 'display-graphic-p) (lambda () t))
+              ((symbol-function 'set-frame-parameter) #'ignore)
+              ((symbol-function 'message) #'ignore))
+      (cj/toggle-transparency)
+      (cj/toggle-transparency))
+    (should (eq cj/enable-transparency t))))
+
+;;; cj/set-cursor-type
+
+(ert-deftest test-ui-config-set-cursor-type-passes-symbol-to-frame ()
+  "Normal: `cj/set-cursor-type' hands NEW-CURSOR-TYPE to `modify-frame-parameters'."
+  (let ((received nil))
+    (cl-letf (((symbol-function 'modify-frame-parameters)
+               (lambda (_frame alist) (setq received alist))))
+      (cj/set-cursor-type 'bar))
+    (should (equal received '((cursor-type . bar))))))
+
+(ert-deftest test-ui-config-set-cursor-type-accepts-nil ()
+  "Boundary: nil is a valid cursor type (means \"invisible\")."
+  (let ((received nil))
+    (cl-letf (((symbol-function 'modify-frame-parameters)
+               (lambda (_frame alist) (setq received alist))))
+      (cj/set-cursor-type nil))
+    (should (equal received '((cursor-type . nil))))))
+
+(provide 'test-ui-config-transparency-and-cursor)
+;;; test-ui-config-transparency-and-cursor.el ends here