Add raw string literal highlighting for C# 11. (highlightjs#3906)

* Add raw string literal highlighting for C# 11.
Fixes issue highlightjs#3868.

This fails the tests as the Vala default.txt is recognised now
as C#. However, Vala is very close in syntax to C#, and the default.txt
also seems to be valid C# so not sure what to do about this.

* (dev) prevent autodetect failures from breaking tests [Josh Goebe]

We are deemphasizing auto-detect - it was never great. Someone who
cares about auto-detect can run the tool, but we will no longer
fail the test suite based on any auto-detect issues.

---------

Co-authored-by: Josh Goebel <me@joshgoebel.com>

Author: TaraLei

CHANGES.md

@@ -15,6 +15,7 @@ Core Grammars:
 - fix(rust) fix for r# raw identifier not being highlighted correctly. [JaeBaek Lee][]
 - enh(rust) Adding union to be recognized as a keyword in Rust. [JaeBaek Lee][]
 - fix(yaml) fix for yaml with keys having brackets highlighted incorrectly [Aneesh Kulkarni][]
+- fix(csharp) add raw string highlighting for C# 11. [Tara][]
 - fix(bash) fix # within token being detected as the start of a comment [Felix Uhl][]
 - fix(python) fix `or` conflicts with string highlighting [Mohamed Ali][]
 - enh(delphi) allow digits to be omitted for hex and binary literals [Jonah Jeleniewski][]
@@ -57,6 +58,7 @@ Themes:
 [Kristian Ekenes]: https://github.com/ekenes
 [Aneesh Kulkarni]: https://github.com/aneesh98
 [Bruno Meneguele]: https://github.com/bmeneg
+[Tara]: https://github.com/taralei
 [Felix Uhl]: https://github.com/iFreilicht
 [nataliia-radina]: https://github.com/Nataliia-Radina
 [Robloxian Demo]: https://github.com/RobloxianDemo

src/languages/csharp.js

@@ -164,6 +164,11 @@ export default function(hljs) {
     ],
     relevance: 0
   };
+  const RAW_STRING = {
+    className: 'string',
+    begin: /"""("*)(?!")(.|\n)*?"""\1/,
+    relevance: 1
+  };
   const VERBATIM_STRING = {
     className: 'string',
     begin: '@"',
@@ -229,6 +234,7 @@ export default function(hljs) {
     hljs.inherit(hljs.C_BLOCK_COMMENT_MODE, { illegal: /\n/ })
   ];
   const STRING = { variants: [
+    RAW_STRING,
     INTERPOLATED_VERBATIM_STRING,
     INTERPOLATED_STRING,
     VERBATIM_STRING,

test/detect/index.js

@@ -31,31 +31,31 @@ function testAutoDetection(language, { detectPath }) {
   });
 }
 
-describe('hljs.highlightAuto()', () => {
-  before(async function() {
-    const thirdPartyPackages = await getThirdPartyPackages();
-
-    const languages = hljs.listLanguages();
-    describe(`hljs.highlightAuto()`, function() {
-      languages.filter(hljs.autoDetection).forEach((language) => {
-        const detectPath = detectTestDir(language);
-        testAutoDetection(language, { detectPath });
-      });
-    });
-
-    // assumes only one package provides the requested module name
-    function detectTestDir(name) {
-      for (let i = 0; i < thirdPartyPackages.length; ++i) {
-        const pkg = thirdPartyPackages[i];
-        const idx = pkg.names.indexOf(name);
-        if (idx !== -1) return pkg.detectTestPaths[idx];
-      }
-      return null; // test not found
-    }
-  });
-
-  it("compiling the grammars", async function() {
-    const languages = hljs.listLanguages();
-    languages.forEach(lang => hljs.highlight("", { language: lang} ))
-  }); // this is also required for the dynamic test generation above to work
-});
+// describe('hljs.highlightAuto()', () => {
+//   before(async function() {
+//     const thirdPartyPackages = await getThirdPartyPackages();
+
+//     const languages = hljs.listLanguages();
+//     describe(`hljs.highlightAuto()`, function() {
+//       languages.filter(hljs.autoDetection).forEach((language) => {
+//         const detectPath = detectTestDir(language);
+//         testAutoDetection(language, { detectPath });
+//       });
+//     });
+
+//     // assumes only one package provides the requested module name
+//     function detectTestDir(name) {
+//       for (let i = 0; i < thirdPartyPackages.length; ++i) {
+//         const pkg = thirdPartyPackages[i];
+//         const idx = pkg.names.indexOf(name);
+//         if (idx !== -1) return pkg.detectTestPaths[idx];
+//       }
+//       return null; // test not found
+//     }
+//   });
+
+//   it("compiling the grammars", async function() {
+//     const languages = hljs.listLanguages();
+//     languages.forEach(lang => hljs.highlight("", { language: lang} ))
+//   }); // this is also required for the dynamic test generation above to work
+// });

test/markup/csharp/string-raw.expect.txt

@@ -0,0 +1,17 @@
+<span class="hljs-comment">// String raw literals since C# 11. &lt;https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/tokens/raw-string&gt;</span>
+
+<span class="hljs-built_in">string</span> longMessage1 = <span class="hljs-string">&quot;&quot;&quot;&quot;
+    This is a long message.
+    It has several lines.
+        Some are indented
+                more than others.
+    Some have &quot;&quot;&quot;quoted text&quot;&quot;&quot; in them. \&quot;
+    &quot;&quot;&quot;&quot;</span>;
+    
+<span class="hljs-built_in">string</span> longMessage2 = <span class="hljs-string">&quot;&quot;&quot;
+    This is a long message.
+    It has several lines.
+        Some are indented
+                more than others.
+    Some have &quot;&quot;quoted text&quot;&quot; in them. \&quot;
+    &quot;&quot;&quot;</span>;

test/markup/csharp/string-raw.txt

@@ -0,0 +1,17 @@
+// String raw literals since C# 11. <https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/tokens/raw-string>
+
+string longMessage1 = """"
+    This is a long message.
+    It has several lines.
+        Some are indented
+                more than others.
+    Some have """quoted text""" in them. \"
+    """";
+    
+string longMessage2 = """
+    This is a long message.
+    It has several lines.
+        Some are indented
+                more than others.
+    Some have ""quoted text"" in them. \"
+    """;