feat(web): experiment with Lezer parser

1 files changed, 82 insertions, 0 deletions

diff --git a/language-web/src/main/js/editor/problemLanguageSupport.ts b/language-web/src/main/js/editor/problemLanguageSupport.ts
new file mode 100644
index 00000000..2bf7c7a4
--- /dev/null
+++ b/language-web/src/main/js/editor/problemLanguageSupport.ts
@@ -0,0 +1,82 @@
+import { styleTags, tags as t } from '@codemirror/highlight';
+import {
+  foldInside,
+  foldNodeProp,
+  indentNodeProp,
+  LanguageSupport,
+  LRLanguage,
+} from '@codemirror/language';
+import { LRParser } from '@lezer/lr';
+
+import { parser } from '../../../../build/generated/sources/lezer/problem';
+import {
+  foldBlockComment,
+  foldConjunction,
+  foldDeclaration,
+} from './folding';
+import {
+  indentBlockComment,
+  indentDeclaration,
+  indentPredicate,
+} from './indentation';
+
+const parserWithMetadata = (parser as LRParser).configure({
+  props: [
+    styleTags({
+      LineComment: t.lineComment,
+      BlockComment: t.blockComment,
+      'problem class enum pred unique scope': t.definitionKeyword,
+      'abstract refers contains opposite error default': t.modifier,
+      'true false unknown error': t.keyword,
+      NotOp: t.keyword,
+      UnknownOp: t.keyword,
+      OrOp: t.keyword,
+      StarArgument: t.keyword,
+      'IntMult StarMult Real': t.number,
+      StarMult: t.number,
+      'RelationName/QualifiedName': t.typeName,
+      'UniqueNodeName/QualifiedName': t.atom,
+      'VariableName/QualifiedName': t.variableName,
+      '{ }': t.brace,
+      '( )': t.paren,
+      '[ ]': t.squareBracket,
+      '. .. , :': t.separator,
+      '<->': t.definitionOperator,
+    }),
+    indentNodeProp.add({
+      ProblemDeclaration: indentDeclaration,
+      UniqueDeclaration: indentDeclaration,
+      ScopeDeclaration: indentDeclaration,
+      PredicateBody: indentPredicate,
+      BlockComment: indentBlockComment,
+    }),
+    foldNodeProp.add({
+      ClassBody: foldInside,
+      EnumBody: foldInside,
+      ParameterList: foldInside,
+      PredicateBody: foldInside,
+      Conjunction: foldConjunction,
+      UniqueDeclaration: foldDeclaration,
+      ScopeDeclaration: foldDeclaration,
+      BlockComment: foldBlockComment,
+    }),
+  ],
+});
+
+const problemLanguage = LRLanguage.define({
+  parser: parserWithMetadata,
+  languageData: {
+    commentTokens: {
+      block: {
+        open: '/*',
+        close: '*/',
+      },
+      line: '%',
+    },
+    indentOnInput: /^\s*(?:\{|\}|\(|\)|;|\.)$/,
+  },
+});
+
+export function problemLanguageSupport(): LanguageSupport {
+  return new LanguageSupport(problemLanguage);
+}