Fix font-family name interpolation and termination

Author: deathaxe

Syntaxes/Less.sublime-syntax

@@ -324,6 +324,23 @@ contexts:
 
 ###[ CSS STRING CONSTANTS ]####################################################
 
+  font-family-names:
+    # replace CSS context to add interpolation support
+    - match: '{{ident_begin}}'
+      push: font-family-name-body
+
+  font-family-name-body:
+    - meta_include_prototype: false
+    - meta_scope: meta.string.css string.unquoted.css
+    - include: less-string-interpolations
+    # allow unquoted space separated font names
+    - match: (?!\s+{{ident_start}}){{break}}
+      pop: 1
+    # function call ahead, skip font name
+    - match: (?=\s+{{ident}}\()
+      pop: 1
+    - match: '{{unicode}}'
+
   language-ranges:
     # replace CSS context to add interpolation support
     - match: '{{lang_range_begin}}'

tests/syntax_test_css.less

@@ -2497,6 +2497,13 @@
     font: sans serif;
 /*        ^^^^^^^^^^ meta.string.css string.unquoted.css */
 
+    font: san\73 -\73 erif;
+/*        ^^^^^^^^^^^^^^^^ meta.string.css string.unquoted.css */
+
+    font: sans serif var(--name);
+/*        ^^^^^^^^^^ meta.string.css string.unquoted.css */
+/*                   ^^^^^^^^^^^ meta.function-call */
+
     font: inherit;
 /*        ^^^^^^^ support - string */
 

tests/syntax_test_less.less

@@ -797,6 +797,15 @@ custom-@{element}-selector {}
 //                                             ^^^^^ variable.other.less
 //                                                   ^^^ support.constant.color.w3c.standard.css
 //                                                       ^ punctuation.section.group.end.css
+
+    font: san\73 -\73 erif;
+//        ^^^^^^^^^^^^^^^^ meta.string.css string.unquoted.css
+
+    font: sans @{serif} var(--name);
+//        ^^^^^ meta.string.css string.unquoted.css
+//             ^^^^^^^^ meta.string.css meta.interpolation.less
+//                     ^ - meta.string - meta.interpolation
+//                      ^^^^^^^^^^^ meta.function-call
 }
 
 //=============================================================================