Upgrade to ohm-js v18 (beta.7) with @ohm-js/compiler and to-ast-compat

Replace ohm-js v17 with ohm-js 18.0.0-beta.7 and its companion
packages (@ohm-js/compiler, @ohm-js/to-ast-compat). This enables
WebAssembly-based parsing for better performance.

- Use createToAst() / closure-based toAst instead of node.toAST(mapping)
- Use `using match` for automatic resource cleanup
- Use typed CstNode, OptNode, MatchResult imports
- Update grammar index offsets for new AST shape
- Adapt to new error API (FailedMatchResult, getRightmostFailurePosition)
- Update test expectations for new error message token ordering

Author: pdubroy

.changeset/ohm-wasm-browser-parsing.md

@@ -0,0 +1,5 @@
+---
+'@shopify/liquid-html-parser': minor
+---
+
+Integrate @ohm-js/wasm for browser-compatible parsing

packages/liquid-html-parser/package.json

@@ -32,8 +32,10 @@
     "type-check": "tsc --noEmit"
   },
   "dependencies": {
+    "@ohm-js/compiler": "18.0.0-beta.7",
+    "@ohm-js/to-ast-compat": "18.0.0-beta.7",
     "line-column": "^1.0.2",
-    "ohm-js": "^17.0.0"
+    "ohm-js": "18.0.0-beta.7"
   },
   "devDependencies": {
     "@types/line-column": "^1.0.0"

packages/liquid-html-parser/src/errors.ts

@@ -1,5 +1,5 @@
 import lineColumn from 'line-column';
-import { MatchResult } from 'ohm-js';
+import { FailedMatchResult } from 'ohm-js';
 import { NodeTypes, Position } from './types';
 
 interface LineColPosition {
@@ -10,12 +10,12 @@ interface LineColPosition {
 export class LiquidHTMLCSTParsingError extends SyntaxError {
   loc?: { start: LineColPosition; end: LineColPosition };
 
-  constructor(ohm: MatchResult) {
+  constructor(ohm: FailedMatchResult) {
     super(ohm.shortMessage);
     this.name = 'LiquidHTMLParsingError';
 
-    const input = (ohm as any).input;
-    const errorPos = (ohm as any)._rightmostFailurePosition;
+    const input = ohm.input;
+    const errorPos = ohm.getRightmostFailurePosition();
     const lineCol = lineColumn(input).fromIndex(Math.min(errorPos, input.length - 1));
 
     // Plugging ourselves into @babel/code-frame since this is how

packages/liquid-html-parser/src/grammar.spec.ts

@@ -101,7 +101,7 @@ describe('Unit: liquidHtmlGrammar', () => {
         expectMatchSucceeded('<6h>').to.be.false;
 
         function expectMatchSucceeded(text: string) {
-          const match = grammar.LiquidHTML.match(text, 'Node');
+          using match = grammar.LiquidHTML.match(text, 'Node');
           return expect(match.succeeded(), text);
         }
       });
@@ -129,7 +129,7 @@ describe('Unit: liquidHtmlGrammar', () => {
         `).to.be.true;
 
         function expectMatchSucceeded(text: string) {
-          const match = grammar.LiquidStatement.match(text.trimStart(), 'Node');
+          using match = grammar.LiquidStatement.match(text.trimStart(), 'Node');
           return expect(match.succeeded(), text);
         }
       });
@@ -156,7 +156,7 @@ describe('Unit: liquidHtmlGrammar', () => {
     });
 
     function expectMatchSucceeded(text: string) {
-      const match = placeholderGrammars.LiquidHTML.match(text.trimStart(), 'Node');
+      using match = placeholderGrammars.LiquidHTML.match(text.trimStart(), 'Node');
       return expect(match.succeeded(), text);
     }
   });

packages/liquid-html-parser/src/grammar.ts

@@ -1,4 +1,4 @@
-import { grammars, Grammar } from 'ohm-js';
+import { grammars, Grammar } from '@ohm-js/compiler/compat';
 
 export const liquidHtmlGrammars = grammars(require('../grammar/liquid-html.ohm.js'));