enh(parser) simplify nohighlight (#2374)

* (chore) make `noHighlightRe` and `languagePrefixRe` configurable (languageDetectRe now)
* (chore) simply 'nohighlight' regex

- Now only `no-highlight` and `nohighlight` skip a block entirely
- `plain` will do nothing
- `text` is now an alias for `plaintext`

Closes #2363.

CHANGES.md

@@ -10,7 +10,7 @@ New themes:
 
 Core Changes:
 
-- none.
+- make `noHighlightRe` and `languagePrefixRe` configurable (#2374) [Josh Goebel][]
 
 Language Improvements:
 
@@ -31,6 +31,7 @@ Developer Tools:
 [Sam Miller]: https://github.com/smillerc
 [Robert Riebisch]: https://github.com/bttrx
 [Taufik Nurrohman]: https://github.com/taufik-nurrohman
+[Josh Goebel]: https://github.com/yyyc514
 
 
 ## Version 9.18.1

README.md

@@ -177,7 +177,7 @@ The table below shows the full list of supported languages (and corresponding cl
 | PHP                     | php, php3, php4, php5, php6, php7 |    |
 | Parser3                 | parser3                |         |
 | Perl                    | perl, pl, pm           |         |
-| Plaintext: no highlight | plaintext              |         |
+| Plaintext               | plaintext, txt, text   |         |
 | Pony                    | pony                   |         |
 | PostgreSQL & PL/pgSQL   | pgsql, postgres, postgresql |    |
 | PowerShell              | powershell, ps, ps1    |         |

VERSION_10_BREAKING.md

@@ -2,6 +2,8 @@
 
 Incompatibilities:
 - chore(parser): compressed version 9.x language definitions no longer supported (rebuild them minified) [Josh Goebel][]
+- `nohightlight` and `no-highlight` are the only "ignore me" css classes now (`plain` and `text` no longer count)
+  (to get the old behavior you can customize `noHighlightRe`)
 
 Renamed Language Files:
 - chore(parser): rename `nimrod.js` to `nim.js` [Josh Goebel][]

docs/api.rst

@@ -74,6 +74,8 @@ Configures global options:
 * ``useBR``: a flag to generate ``<br>`` tags instead of new-line characters in the output, useful when code is marked up using a non-``<pre>`` container.
 * ``classPrefix``: a string prefix added before class names in the generated markup, used for backwards compatibility with stylesheets.
 * ``languages``: an array of language names and aliases restricting auto detection to only these languages.
+* ``languageDetectRe``: a regex to configure how CSS class names map to language (allows class names like say `color-as-php` vs the default of `language-php`, etc.)
+* ``noHighlightRe``: a regex to configure which CSS classes are to be skipped completely
 
 Accepts an object representing options with the values to updated. Other options don't change
 ::

src/highlight.js

@@ -42,9 +42,7 @@ https://highlightjs.org/
   var SAFE_MODE = true;
 
   // Regular expressions used throughout the highlight.js library.
-  var noHighlightRe    = /^(no-?highlight|plain|text)$/i,
-      languagePrefixRe = /\blang(?:uage)?-([\w-]+)\b/i,
-      fixMarkupRe      = /((^(<[^>]+>|\t|)+|(?:\n)))/gm;
+  var fixMarkupRe      = /((^(<[^>]+>|\t|)+|(?:\n)))/gm;
 
   // The object will be assigned by the build tool. It used to synchronize API
   // of external language files with minified version of the highlight.js library.
@@ -56,6 +54,8 @@ https://highlightjs.org/
   // Global options used when within external APIs. This is modified when
   // calling the `hljs.configure` function.
   var options = {
+    noHighlightRe: /^(no-?highlight)$/i,
+    languageDetectRe: /\blang(?:uage)?-([\w-]+)\b/i,
     classPrefix: 'hljs-',
     tabReplace: null,
     useBR: false,
@@ -82,7 +82,7 @@ https://highlightjs.org/
   }
 
   function isNotHighlighted(language) {
-    return noHighlightRe.test(language);
+    return options.noHighlightRe.test(language);
   }
 
   function blockLanguage(block) {
@@ -92,7 +92,7 @@ https://highlightjs.org/
     classes += block.parentNode ? block.parentNode.className : '';
 
     // language-* takes precedence over non-prefixed class names.
-    match = languagePrefixRe.exec(classes);
+    match = options.languageDetectRe.exec(classes);
     if (match) {
       var language = getLanguage(match[1]);
       if (!language) {

test/fixtures/index.html

@@ -71,12 +71,6 @@
 <pre><code class="no-highlight">&lt;div id="contents"&gt;
   &lt;p&gt;Hello, World!
 &lt;/div&gt;</code></pre>
-<pre><code class="plain">&lt;div id="contents"&gt;
-  &lt;p&gt;Hello, World!
-&lt;/div&gt;</code></pre>
-<pre><code class="text">&lt;div id="contents"&gt;
-  &lt;p&gt;Hello, World!
-&lt;/div&gt;</code></pre>
 
 <!-- non-code <pre> -->
 <pre><samp>Computer output</samp></pre>
@@ -90,10 +84,6 @@
 <!-- unsupported prefixed language and supported unprefixed language -->
 <pre><code class="python language-foo">for x in [1, 2, 3]: count(x)</code></pre>
 
-<!-- class name with no highlighting keyword (eg: 'plain' or 'text') -->
-<pre><code class="text-content javascript">var x = 'foo';</code></pre>
-<pre><code class="clipboard-text javascript">var x = 'foo';</code></pre>
-
 </div>
 
 <!-- sub-languages -->

test/special/noHighlight.js

@@ -30,59 +30,32 @@ describe('no highlighting', () => {
     actual.should.equal(expected);
   });
 
-  it('should keep block unchanged (plain)', () => {
-    const expected = this.expected.html,
-          actual   = this.blocks[2];
-
-    actual.should.equal(expected);
-  });
-
-  it('should keep block unchanged (text)', () => {
-    const expected = this.expected.html,
-          actual   = this.blocks[3];
-
-    actual.should.equal(expected);
-  });
-
   it('should skip pre tags without a child code tag', () => {
     const expected = 'Computer output',
-          actual   = this.blocks[4];
+          actual   = this.blocks[2];
 
     actual.should.equal(expected);
   });
 
   it('should keep block unchanged (unsupported language)', () => {
     const expected = this.expected.python,
-          actual   = this.blocks[5];
+          actual   = this.blocks[3];
 
     actual.should.equal(expected);
   });
 
   it('should keep block unchanged (unsupported lang)', () => {
     const expected = this.expected.python,
-          actual   = this.blocks[6];
+          actual   = this.blocks[4];
 
     actual.should.equal(expected);
   });
 
   it('should keep block unchanged (unsupported prefixed language)', () => {
     const expected = this.expected.python,
-          actual   = this.blocks[7];
-
-    actual.should.equal(expected);
-  });
-
-  it('should highlight class names containing text at the start', () => {
-    const expected = this.expected.javascript,
-          actual   = this.blocks[8];
+          actual   = this.blocks[5];
 
     actual.should.equal(expected);
   });
 
-  it('should highlight class names containing text at the end', () => {
-    const expected = this.expected.javascript,
-          actual   = this.blocks[9];
-
-    actual.should.equal(expected);
-  });
 });