Don't convert the tree to JSON before checking it. Just check it directly.

Author: CyrusNajmabadi

src/harness/fourslash.ts

@@ -1434,12 +1434,7 @@ module FourSlash {
  this.raiseError('Mismatched incremental/reference syntactic diagnostics for file ' + this.activeFile.fileName + '.\n=== Incremental diagnostics ===\n' + incrementalSyntaxDiagnostics + '\n=== Reference Diagnostics ===\n' + referenceSyntaxDiagnostics);
  }
 
- var incrementalSourceFileJSON = Utils.sourceFileToJSON(incrementalSourceFile);
- var referenceSourceFileJSON = Utils.sourceFileToJSON(referenceSourceFile);
-
- if (incrementalSyntaxDiagnostics !== referenceSyntaxDiagnostics) {
- this.raiseError('Mismatched incremental/reference ast for file ' + this.activeFile.fileName + '.\n=== Incremental AST ===\n' + incrementalSourceFileJSON + '\n=== Reference AST ===\n' + referenceSourceFileJSON);
- }
+ Utils.assertStructuralEquals(incrementalSourceFile, referenceSourceFile);
 
  //if (this.editValidation !== IncrementalEditValidation.SyntacticOnly) {
  // var compiler = new TypeScript.TypeScriptCompiler();