Add color highlighting to css-mode

Bug#25525
* lisp/textmodes/css-mode.el (css--color-map): New constant.
(css-value-class-alist): Use css--color-map.
(css--number-regexp, css--percent-regexp)
(css--number-or-percent-regexp, css--angle-regexp): New constants.
(css--color-skip-blanks, css--rgb-color, css--hsl-color): New
functions.
(css--colors-regexp): New constant.
(css--hex-color, css--named-color, css--compute-color)
(css--contrasty-color, css--fontify-colors)
(css--fontify-region): New functions.
(css-mode): Set font-lock-fontify-region-function.
(css-mode-syntax-table): Set syntax on more characters.
(css-fontify-colors): New defcustom.
(scss-mode-syntax-table): Define syntax for ?$ and ?%.
* test/lisp/textmodes/css-mode-tests.el (css-test-property-values):
Update.
(css-test-rgb-parser, css-test-hsl-parser)
(css-test-named-color): New tests.
* etc/NEWS: Add entry.

1 files changed, 45 insertions, 1 deletions

diff --git a/test/lisp/textmodes/css-mode-tests.el b/test/lisp/textmodes/css-mode-tests.el
index d601f43002a..b4666ae72d7 100644
--- a/test/lisp/textmodes/css-mode-tests.el
+++ b/test/lisp/textmodes/css-mode-tests.el
@@ -58,7 +58,7 @@
 
   ;; Check that the `color' property doesn't cause infinite recursion
   ;; because it refers to the value class of the same name.
-  (should (= (length (css--property-values "color")) 147)))
+  (should (= (length (css--property-values "color")) 152)))
 
 (ert-deftest css-test-property-value-cache ()
   "Test that `css--property-value-cache' is in use."
@@ -234,5 +234,49 @@
       (save-excursion (insert (nth 1 item)))
       (should (equal (nth 2 item) (css--mdn-find-symbol))))))
 
+(ert-deftest css-test-rgb-parser ()
+  (with-temp-buffer
+    (css-mode)
+    (dolist (input '("255, 0, 127"
+                     "255, /* comment */ 0, 127"
+                     "255 0 127"
+                     "255, 0, 127, 0.75"
+                     "255 0 127 / 0.75"
+                     "100%, 0%, 50%"
+                     "100%, 0%, 50%, 0.115"
+                     "100% 0% 50%"
+                     "100% 0% 50% / 0.115"))
+      (erase-buffer)
+      (save-excursion
+        (insert input ")"))
+      (should (equal (css--rgb-color) "#ff007f")))))
+
+(ert-deftest css-test-hsl-parser ()
+  (with-temp-buffer
+    (css-mode)
+    (dolist (input '("0, 100%, 50%"
+                     "0 100% 50%"
+                     "0 /* two */ /* comments */100% 50%"
+                     "0, 100%, 50%, 0.75"
+                     "0 100% 50% / 0.75"
+                     "0deg 100% 50%"
+                     "360deg 100% 50%"
+                     "0rad, 100%, 50%, 0.115"
+                     "0grad, 100%, 50%, 0.115"
+                     "1turn 100% 50% / 0.115"))
+      (erase-buffer)
+      (save-excursion
+        (insert input ")"))
+      (should (equal (css--hsl-color) "#ff0000")))))
+
+(ert-deftest css-test-named-color ()
+  (dolist (text '("@mixin black" "@include black"))
+    (with-temp-buffer
+      (insert text)
+      (should-not (css--named-color (save-excursion
+                                      (backward-word)
+                                      (point))
+                                    "black")))))
+
 (provide 'css-mode-tests)
 ;;; css-mode-tests.el ends here