fix(rust) ensure brackets are balanced within attributes

CHANGES.md

@@ -8,12 +8,14 @@ Core Grammars:
 
 - enh(csp) add missing directives / keywords from MDN (7 more) [Max Liashuk][]
 - enh(ada) add new `parallel` keyword, allow `[]` for Ada 2022 [Max Reznik][]
+- fix(rust) ensure brackets are balanced within attributes [ewwwin][]
 
 CONTRIBUTORS
 
 [Josh Marchand]: https://github.com/yHSJ
 [Max Liashuk]: https://github.com/probil
 [Max Reznik]: https://github.com/reznikmm
+[ewwwin]: https://github.com/ewwwin
 
 ## Version 11.11.1
 

src/languages/rust.js

@@ -25,6 +25,12 @@ export default function(hljs) {
       IDENT_RE,
       regex.lookahead(/\s*\(/))
   };
+  const META_STRING = {
+    className: 'string',
+    begin: /"/,
+    end: /"/,
+    contains: [ hljs.BACKSLASH_ESCAPE ]
+  };
   const NUMBER_SUFFIX = '([ui](8|16|32|64|128|size)|f(32|64))\?';
   const KEYWORDS = [
     "abstract",
@@ -246,14 +252,28 @@ export default function(hljs) {
         begin: '#!?\\[',
         end: '\\]',
         contains: [
+          META_STRING,
           {
-            className: 'string',
-            begin: /"/,
-            end: /"/,
+            relevance: 0,
+            variants: [
+              {
+                begin: /\(/,
+                end: /\)/,
+              },
+              {
+                begin: /\[/,
+                end: /\]/,
+              },
+              {
+                begin: /\{/,
+                end: /\}/,
+              },
+            ],
             contains: [
-              hljs.BACKSLASH_ESCAPE
+              'self',
+              META_STRING,
             ]
-          }
+          },
         ]
       },
       {

test/markup/rust/attributes.expect.txt

@@ -0,0 +1,18 @@
+<span class="hljs-meta">#[foo]</span>
+<span class="hljs-meta">#![foo]</span>
+
+<span class="hljs-meta">#[foo(bar)]</span>
+<span class="hljs-meta">#[foo = bar]</span>
+<span class="hljs-meta">#[foo(<span class="hljs-string">&quot;a \&quot;b\&quot; c&quot;</span>)]</span>
+<span class="hljs-meta">#[foo(bar = [a, b, c])]</span>
+<span class="hljs-meta">#[foo[bar]]</span>
+<span class="hljs-meta">#[foo{bar}]</span>
+
+<span class="hljs-meta">#![no_std]</span>
+<span class="hljs-meta">#[doc = <span class="hljs-string">&quot;example&quot;</span>]</span>
+<span class="hljs-meta">#[allow(unused, clippy::inline_always)]</span>
+<span class="hljs-meta">#[macro_use(foo, bar)]</span>
+<span class="hljs-meta">#[link(name = <span class="hljs-string">&quot;CoreFoundation&quot;</span>, kind = <span class="hljs-string">&quot;framework&quot;</span>)]</span>
+
+<span class="hljs-meta">#[rtic::app(device = lm3s6965, dispatchers = [UART0, UART1])]</span>
+<span class="hljs-meta">#[task(binds = USB_OTG1, local = [poller])]</span>

test/markup/rust/attributes.txt

@@ -0,0 +1,18 @@
+#[foo]
+#![foo]
+
+#[foo(bar)]
+#[foo = bar]
+#[foo("a \"b\" c")]
+#[foo(bar = [a, b, c])]
+#[foo[bar]]
+#[foo{bar}]
+
+#![no_std]
+#[doc = "example"]
+#[allow(unused, clippy::inline_always)]
+#[macro_use(foo, bar)]
+#[link(name = "CoreFoundation", kind = "framework")]
+
+#[rtic::app(device = lm3s6965, dispatchers = [UART0, UART1])]
+#[task(binds = USB_OTG1, local = [poller])]