Don't lowercase Markdown link definition labels

changelog_unreleased/markdown/13155.md

@@ -0,0 +1,20 @@
+#### Don't lowercase link references (#13155 by @DerekNonGeneric & @fisker)
+
+<!-- prettier-ignore -->
+```markdown
+<!-- Input -->
+We now don't strictly follow the release notes format suggested by [Keep a Changelog].
+
+[Keep a Changelog]: https://example.com/
+
+<!-- Prettier stable -->
+We now don't strictly follow the release notes format suggested by [Keep a Changelog].
+
+[keep a changelog]: https://example.com/
+<!--
+^^^^^^^^^^^^^^^^^^ lowercased
+-->
+
+<!-- Prettier main -->
+<Same as input>
+```

package.json

@@ -36,6 +36,7 @@
     "chalk": "5.0.1",
     "ci-info": "3.3.0",
     "cjk-regex": "2.0.1",
+    "collapse-white-space": "1.0.6",
     "cosmiconfig": "7.0.1",
     "css-units-list": "1.1.0",
     "dashify": "2.0.0",

src/language-markdown/clean.js

@@ -1,5 +1,6 @@
 "use strict";
 
+const collapseWhiteSpace = require("collapse-white-space");
 const { isFrontMatterNode } = require("../common/util.js");
 const { startWithPragma } = require("./pragma.js");
 
@@ -42,11 +43,12 @@ function clean(ast, newObj, parent) {
     newObj.value = ast.value.trim().replace(/[\t\n]+/g, " ");
   }
 
-  if (ast.type === "definition" || ast.type === "linkReference") {
-    newObj.label = ast.label
-      .trim()
-      .replace(/[\t\n ]+/g, " ")
-      .toLowerCase();
+  if (
+    ast.type === "definition" ||
+    ast.type === "linkReference" ||
+    ast.type === "imageReference"
+  ) {
+    newObj.label = collapseWhiteSpace(ast.label);
   }
 
   if (

src/language-markdown/printer-markdown.js

@@ -1,5 +1,6 @@
 "use strict";
 
+const collapseWhiteSpace = require("collapse-white-space");
 const {
   getLast,
   getMinNotPresentContinuousCount,
@@ -352,15 +353,15 @@ function genericPrint(path, options, print) {
         printChildren(path, options, print),
         "]",
         node.referenceType === "full"
-          ? ["[", node.identifier, "]"]
+          ? printLinkReference(node)
           : node.referenceType === "collapsed"
           ? "[]"
           : "",
       ];
     case "imageReference":
       switch (node.referenceType) {
         case "full":
-          return ["![", node.alt || "", "][", node.identifier, "]"];
+          return ["![", node.alt || "", "]", printLinkReference(node)];
         default:
           return [
             "![",
@@ -372,9 +373,8 @@ function genericPrint(path, options, print) {
     case "definition": {
       const lineOrSpace = options.proseWrap === "always" ? line : " ";
       return group([
-        "[",
-        node.identifier,
-        "]:",
+        printLinkReference(node),
+        ":",
         indent([
           lineOrSpace,
           printUrl(node.url),
@@ -390,7 +390,7 @@ function genericPrint(path, options, print) {
     case "footnote":
       return ["[^", printChildren(path, options, print), "]"];
     case "footnoteReference":
-      return ["[^", node.identifier, "]"];
+      return printFootnoteReference(node);
     case "footnoteDefinition": {
       const nextNode = path.getParentNode().children[path.getName() + 1];
       const shouldInlineFootnote =
@@ -401,9 +401,8 @@ function genericPrint(path, options, print) {
             node.children[0].position.start.line ===
               node.children[0].position.end.line));
       return [
-        "[^",
-        node.identifier,
-        "]: ",
+        printFootnoteReference(node),
+        ": ",
         shouldInlineFootnote
           ? printChildren(path, options, print)
           : group([
@@ -913,6 +912,16 @@ function hasPrettierIgnore(path) {
   return isPrettierIgnore(prevNode) === "next";
 }
 
+// `remark-parse` lowercase the `label` as `identifier`, we don't want do that
+// https://github.com/remarkjs/remark/blob/daddcb463af2d5b2115496c395d0571c0ff87d15/packages/remark-parse/lib/tokenize/reference.js
+function printLinkReference(node) {
+  return `[${collapseWhiteSpace(node.label)}]`;
+}
+
+function printFootnoteReference(node) {
+  return `[^${node.label}]`;
+}
+
 module.exports = {
   preprocess,
   print: genericPrint,

tests/format/markdown/linkReference/case-and-space/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,114 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`case-and-space.md format 1`] = `
+====================================options=====================================
+parsers: ["markdown"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+# \`linkReference\`
+
+[   See   \`AsyncGeneratorFunction\`   ][   See   \`AsyncGeneratorFunction\`   ]
+
+# \`imageReference\`
+
+![   See   \`AsyncGeneratorFunction\`   ][   See   \`AsyncGeneratorFunction\`   ]
+
+# \`definition\`
+
+[   See   \`AsyncGeneratorFunction\`   ]: ./index.html
+
+# \`footnoteReference\`
+
+[^See\`AsyncGeneratorFunction\`]
+
+# \`footnoteDefinition\`
+
+[^See\`AsyncGeneratorFunction\`]: ./index.html
+
+=====================================output=====================================
+# \`linkReference\`
+
+[ See \`AsyncGeneratorFunction\` ][ See \`AsyncGeneratorFunction\` ]
+
+# \`imageReference\`
+
+![   See   \`AsyncGeneratorFunction\`   ][ See \`AsyncGeneratorFunction\` ]
+
+# \`definition\`
+
+[ See \`AsyncGeneratorFunction\` ]: ./index.html
+
+# \`footnoteReference\`
+
+[^See\`AsyncGeneratorFunction\`]
+
+# \`footnoteDefinition\`
+
+[^See\`AsyncGeneratorFunction\`]: ./index.html
+
+================================================================================
+`;
+
+exports[`issue-3835.md format 1`] = `
+====================================options=====================================
+parsers: ["markdown"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+[1][Test Text](http://example.com)
+
+=====================================output=====================================
+[1][Test Text](http://example.com)
+
+================================================================================
+`;
+
+exports[`issue-7118.md format 1`] = `
+====================================options=====================================
+parsers: ["markdown"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+- see[Link to Foo][master-LinkToFoo]
+
+[master-LinkToFoo]: http://foo.com
+
+Bla bla [PascalCase][] bla.
+
+[PascalCase]: ./PascalCase.md
+
+## [Unreleased]
+…
+[Unreleased]: https://github.com/username/project/compare/v1.0.0...HEAD
+
+[darktable]: https://www.darktable.org/
+[js;dr]: https://indieweb.org/js;dr
+[LinuxFest Northwest]: https://www.linuxfestnorthwest.org/
+[OpenStreetMap]: https://www.openstreetmap.org/about
+[SeaGL]: https://seagl.org/
+[uBlock Origin]: https://github.com/gorhill/uBlock
+
+=====================================output=====================================
+- see[Link to Foo][master-LinkToFoo]
+
+[master-LinkToFoo]: http://foo.com
+
+Bla bla [PascalCase][] bla.
+
+[PascalCase]: ./PascalCase.md
+
+## [Unreleased]
+
+…
+[Unreleased]: https://github.com/username/project/compare/v1.0.0...HEAD
+
+[darktable]: https://www.darktable.org/
+[js;dr]: https://indieweb.org/js;dr
+[LinuxFest Northwest]: https://www.linuxfestnorthwest.org/
+[OpenStreetMap]: https://www.openstreetmap.org/about
+[SeaGL]: https://seagl.org/
+[uBlock Origin]: https://github.com/gorhill/uBlock
+
+================================================================================
+`;

tests/format/markdown/linkReference/case-and-space/case-and-space.md

@@ -0,0 +1,19 @@
+# `linkReference`
+
+[   See   `AsyncGeneratorFunction`   ][   See   `AsyncGeneratorFunction`   ]
+
+# `imageReference`
+
+![   See   `AsyncGeneratorFunction`   ][   See   `AsyncGeneratorFunction`   ]
+
+# `definition`
+
+[   See   `AsyncGeneratorFunction`   ]: ./index.html
+
+# `footnoteReference`
+
+[^See`AsyncGeneratorFunction`]
+
+# `footnoteDefinition`
+
+[^See`AsyncGeneratorFunction`]: ./index.html

tests/format/markdown/linkReference/case-and-space/issue-3835.md

@@ -0,0 +1 @@
+[1][Test Text](http://example.com)

tests/format/markdown/linkReference/case-and-space/issue-7118.md

@@ -0,0 +1,18 @@
+- see[Link to Foo][master-LinkToFoo]
+
+[master-LinkToFoo]: http://foo.com
+
+Bla bla [PascalCase][] bla.
+
+[PascalCase]: ./PascalCase.md
+
+## [Unreleased]
+…
+[Unreleased]: https://github.com/username/project/compare/v1.0.0...HEAD
+
+[darktable]: https://www.darktable.org/
+[js;dr]: https://indieweb.org/js;dr
+[LinuxFest Northwest]: https://www.linuxfestnorthwest.org/
+[OpenStreetMap]: https://www.openstreetmap.org/about
+[SeaGL]: https://seagl.org/
+[uBlock Origin]: https://github.com/gorhill/uBlock

tests/format/markdown/linkReference/case-and-space/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, ["markdown"]);

tests/format/markdown/spec/__snapshots__/jsfmt.spec.js.snap

@@ -3074,7 +3074,7 @@ proseWrap: "always"
 [Foo*bar\\]]
 
 =====================================output=====================================
-[foo*bar\\]]: my_(url) "title (with parens)"
+[Foo*bar\\]]: my_(url) "title (with parens)"
 
 [Foo*bar\\]]
 
@@ -3095,7 +3095,7 @@ proseWrap: "always"
 [Foo bar]
 
 =====================================output=====================================
-[foo bar]: my%20url "title"
+[Foo bar]: my%20url "title"
 
 [Foo bar]
 
@@ -3235,7 +3235,7 @@ proseWrap: "always"
 [Foo]
 
 =====================================output=====================================
-[foo]: /url
+[FOO]: /url
 
 [Foo]
 
@@ -3254,7 +3254,7 @@ proseWrap: "always"
 [αγω]
 
 =====================================output=====================================
-[αγω]: /φου
+[ΑΓΩ]: /φου
 
 [αγω]
 
@@ -8889,7 +8889,7 @@ proseWrap: "always"
 [bar]: /url "title"
 
 =====================================output=====================================
-[foo][bar]
+[foo][BaR]
 
 [bar]: /url "title"
 
@@ -8908,9 +8908,9 @@ proseWrap: "always"
 [ТОЛПОЙ]: /url
 
 =====================================output=====================================
-[Толпой][толпой] is a Russian word.
+[Толпой][Толпой] is a Russian word.
 
-[толпой]: /url
+[ТОЛПОЙ]: /url
 
 ================================================================================
 `;
@@ -8928,9 +8928,9 @@ proseWrap: "always"
 [Baz][Foo bar]
 
 =====================================output=====================================
-[foo bar]: /url
+[Foo bar]: /url
 
-[Baz][foo bar]
+[Baz][Foo bar]
 
 ================================================================================
 `;
@@ -9558,7 +9558,7 @@ proseWrap: "always"
 =====================================output=====================================
 ![foo *bar*][foobar]
 
-[foobar]: train.jpg "train & tracks"
+[FOOBAR]: train.jpg "train & tracks"
 
 ================================================================================
 `;
@@ -9656,7 +9656,7 @@ proseWrap: "always"
 =====================================output=====================================
 ![foo][bar]
 
-[bar]: /url
+[BAR]: /url
 
 ================================================================================
 `;

yarn.lock

@@ -2344,7 +2344,7 @@ co@^4.6.0:
   resolved "https://registry.yarnpkg.com/co/-/co-4.6.0.tgz#6ea6bdf3d853ae54ccb8e47bfa0bf3f9031fb184"
   integrity sha1-bqa989hTrlTMuOR7+gvz+QMfsYQ=
 
-collapse-white-space@^1.0.2:
+collapse-white-space@1.0.6, collapse-white-space@^1.0.2:
   version "1.0.6"
   resolved "https://registry.yarnpkg.com/collapse-white-space/-/collapse-white-space-1.0.6.tgz#e63629c0016665792060dbbeb79c42239d2c5287"
   integrity sha512-jEovNnrhMuqyCcjfEJA56v0Xq8SkIoPKDyaHahwo3POf4qcSXqMYuwNcOTzp74vTsR9Tn08z4MxWqAhcekogkQ==