Catch parse errors from babylon gracefully (#486)

nuprl · Apr 17, 2021 · 10d6aa2 · 10d6aa2
1 parent 3ac8225
commit 10d6aa2
Show file tree

Hide file tree

Showing 4 changed files with 42 additions and 6 deletions.
diff --git a/stopify/js/api.test.js b/stopify/js/api.test.js
@@ -0,0 +1,17 @@
+require("../dist/stopify-full.bundle.js");
+
+test('strict mode parse error from stopifyLocally', () => {
+    // The use strict makes the Babylon parser crash.
+    var runner = window.stopify.stopifyLocally(`"use strict"; function F(x,x) { }`);
+    expect(runner.kind).toBe('error');
+});
+
+test('strict mode parse error from evalAsync', (done) => {
+    // The use strict makes the Babylon parser crash.
+    var runner = window.stopify.stopifyLocally(``);
+    expect(runner.kind).toBe('ok');
+    runner.evalAsync(`"use strict"; function F(x,x) { }`, (result) => {
+        expect(result.type).toBe('exception');
+        done();
+    });
+});
diff --git a/stopify/js/stopify-webpack.config.js b/stopify/js/stopify-webpack.config.js
@@ -3,7 +3,7 @@ const runtimeOnly = {
   output: {
     filename: 'dist/stopify.bundle.js',
     library: 'stopify',
-    libraryTarget: 'var'
+    libraryTarget: 'window'
   },
   devtool: 'source-map',
   node: {
@@ -18,7 +18,7 @@ const compilerAndRuntime = {
   output: {
     filename: 'dist/stopify-full.bundle.js',
     library: 'stopify',
-    libraryTarget: 'var'
+    libraryTarget: 'window'
   },
   devtool: 'source-map',
   node: {

diff --git a/stopify/package.json b/stopify/package.json
@@ -78,7 +78,8 @@
   },
   "jest": {
     "roots": [
-      "<rootDir>/dist/test"
+      "<rootDir>/dist/test",
+      "<rootDir>/js"
     ]
   }
 }
diff --git a/stopify/src/entrypoints/compiler.ts b/stopify/src/entrypoints/compiler.ts
@@ -18,6 +18,7 @@ export * from '@stopify/continuations/dist/src/runtime/implicitApps';
 export { knownBuiltIns } from '@stopify/continuations/dist/src/common/cannotCapture';
 export { Result } from '@stopify/continuations-runtime';
 export { AsyncRun, AsyncEval, Error, CompilerOpts, RuntimeOpts };
+import * as util from '@stopify/util';
 
 import * as compiler from '../stopify/compileFunction';
 export { compiler };
@@ -59,7 +60,7 @@ class Runner extends AbstractRunner {
     this.runInit(onDone, onYield, onBreakpoint);
     eval.call(global, this.code);
   }
-
+  
   compile(src: string): string {
     const ast = babylon.parse(src).program;
     return compileFromAst(ast, this.evalOpts);
@@ -80,7 +81,11 @@ class Runner extends AbstractRunner {
   }
 
   evalAsync(src: string, onDone: (result: Result) => void): void {
-    this.evalAsyncFromAst(babylon.parse(src).program, onDone);
+    let ast = parseOrError(src);
+    if (ast.kind == 'error') {
+      return onDone({ type: 'exception', value: ast.exception, stack: [] });
+    }
+    this.evalAsyncFromAst(ast.value, onDone);
   }
 }
 
@@ -112,6 +117,15 @@ export function stopifyLocallyFromAst(
   }
 }
 
+function parseOrError(src: string): { kind: 'program', value: t.Program } | Error {
+  try {
+    return { kind: 'program', value: babylon.parse(src).program };
+  }
+  catch (exn) {
+    return { kind: 'error', exception: exn };
+  }
+}
+
 /**
  * Control the execution of a pre-compiled program.
  *
@@ -122,8 +136,12 @@ export function stopifyLocally(
   src: string,
   optionalCompileOpts?: Partial<CompilerOpts>,
   optionalRuntimeOpts?: Partial<RuntimeOpts>): (AsyncRun & AsyncEval) | Error {
+  let ast = parseOrError(src);
+  if (ast.kind === 'error') {
+    return ast;
+  }
   return stopifyLocallyFromAst(
-    babylon.parse(src).program,
+    ast.value,
     getSourceMap(src),
     optionalCompileOpts,
     optionalRuntimeOpts);