Extract CodeMirror language package

2026-07-09 03:49:44 +09:00
parent 375bc80a57
commit e4b9247c45
19 changed files with 397 additions and 14 deletions
@@ -0,0 +1,77 @@
+import { HighlightStyle, LRLanguage, LanguageSupport, foldNodeProp, indentNodeProp, syntaxHighlighting } from 'npm:@codemirror/language@^6.12.4';
+import { styleTags, tags as t } from 'npm:@lezer/highlight@^1.2.3';
+import { parser } from './decodal-parser-jsr.js';
+
+const parserWithMetadata = parser.configure({
+  props: [
+    styleTags({
+      'Let In Match Import Default': t.keyword,
+      'True False': t.bool,
+      Identifier: t.variableName,
+      String: t.string,
+      Regex: t.regexp,
+      'Integer Float': t.number,
+      Comment: t.lineComment,
+      'Plus Minus Star Slash PlusPlus Equal EqualEqual Bang BangEqual Amp AmpAmp PipePipe SlashSlash Gt Gte Lt Lte Arrow': t.operator,
+      'LBrace RBrace': t.brace,
+      'LBracket RBracket': t.squareBracket,
+      'LParen RParen': t.paren,
+      'Semicolon Comma Dot Colon': t.punctuation,
+    }),
+    indentNodeProp.add({
+      Object: context => context.column(context.node.from) + context.unit,
+      Array: context => context.column(context.node.from) + context.unit,
+      MatchExpression: context => context.column(context.node.from) + context.unit,
+      LetExpression: context => context.column(context.node.from) + context.unit,
+    }),
+    foldNodeProp.add({
+      Object: foldDelimited('{', '}'),
+      Array: foldDelimited('[', ']'),
+      MatchExpression: foldDelimited('{', '}'),
+    }),
+  ],
+});
+
+function foldDelimited(open: string, close: string) {
+  return (node: { from: number; to: number }, state: { doc: { sliceString(from: number, to: number): string } }) => {
+    const text = state.doc.sliceString(node.from, node.to);
+    const openIndex = text.indexOf(open);
+    const closeIndex = text.lastIndexOf(close);
+    if (openIndex < 0 || closeIndex <= openIndex) return null;
+    const from = node.from + openIndex + open.length;
+    const to = node.from + closeIndex;
+    return from < to ? { from, to } : null;
+  };
+}
+
+export const decodalLanguage: LRLanguage = LRLanguage.define({
+  parser: parserWithMetadata,
+  languageData: {
+    commentTokens: { line: '#' },
+    closeBrackets: { brackets: ['(', '[', '{', '"'] },
+  },
+});
+
+export const decodalHighlightStyle: HighlightStyle = HighlightStyle.define([
+  { tag: t.keyword, color: '#93c5fd', fontWeight: '700' },
+  { tag: t.variableName, color: 'inherit' },
+  { tag: t.bool, color: '#fbbf24' },
+  { tag: t.number, color: '#fbbf24' },
+  { tag: t.string, color: '#86efac' },
+  { tag: t.regexp, color: '#86efac' },
+  { tag: t.lineComment, color: '#94a3b8', fontStyle: 'italic' },
+  { tag: t.operator, color: '#f9a8d4' },
+  { tag: [t.brace, t.squareBracket, t.paren, t.punctuation], color: '#f9a8d4' },
+]);
+
+export interface DecodalOptions {
+  highlight?: boolean;
+}
+
+export function decodal(options: DecodalOptions = {}): LanguageSupport {
+  const { highlight = true } = options;
+  return new LanguageSupport(
+    decodalLanguage,
+    highlight ? [syntaxHighlighting(decodalHighlightStyle)] : [],
+  );
+}