Merge pull request #33 from Agoric/eval-sloppy-globals

Eval sloppy globals

src/realm.js

@@ -89,7 +89,7 @@ function initRootRealm(parentUnsafeRec, self, options) {
 
   // todo: investigate attacks via Array.species
   // todo: this accepts newShims='string', but it should reject that
-  const { shims: newShims, transforms } = options;
+  const { shims: newShims, transforms, sloppyGlobals } = options;
   const allShims = arrayConcat(parentUnsafeRec.allShims, newShims);
 
   // The unsafe record is created already repaired.
@@ -108,7 +108,7 @@ function initRootRealm(parentUnsafeRec, self, options) {
 
   // Creating the realmRec provides the global object, eval() and Function()
   // to the realm.
-  const realmRec = createRealmRec(unsafeRec, transforms, options.sloppyGlobals);
+  const realmRec = createRealmRec(unsafeRec, transforms, sloppyGlobals);
 
   // Apply all shims in the new RootRealm. We don't do this for compartments.
   const { safeEvalWhichTakesEndowments } = realmRec;
@@ -127,11 +127,8 @@ function initRootRealm(parentUnsafeRec, self, options) {
 function initCompartment(unsafeRec, self, options = {}) {
   // note: 'self' is the instance of the Realm.
 
-  const realmRec = createRealmRec(
-    unsafeRec,
-    options.transforms,
-    options.sloppyGlobals
-  );
+  const { transforms, sloppyGlobals } = options;
+  const realmRec = createRealmRec(unsafeRec, transforms, sloppyGlobals);
 
   // The realmRec acts as a private field on the realm instance.
   registerRealmRecForRealmInstance(self, realmRec);

src/scopeHandler.js

@@ -75,14 +75,6 @@ export function createScopeHandler(unsafeRec, safeGlobal, sloppyGlobals) {
         return target[prop];
       }
 
-      // Sloppy global properties.
-      if (sloppyGlobals) {
-        if (prop in sloppyGlobals) {
-          return sloppyGlobals[prop];
-        }
-        throw ReferenceError(`${prop} is not defined`);
-      }
-
       // Prevent the lookup for other properties.
       return undefined;
     },
@@ -98,12 +90,6 @@ export function createScopeHandler(unsafeRec, safeGlobal, sloppyGlobals) {
         throw new TypeError(`do not modify endowments like ${String(prop)}`);
       }
 
-      if (sloppyGlobals && !(prop in safeGlobal)) {
-        // We want to capture new assignments to the global scope.
-        sloppyGlobals[prop] = value;
-        return true;
-      }
-
       safeGlobal[prop] = value;
 
       // Return true after successful set.

test/module/evaluators.js

@@ -90,7 +90,7 @@ test('createSafeEvaluatorWhichTakesEndowments - options.sloppyGlobals', t => {
     });
 
     const realmTransforms = [];
-    const sloppyGlobals = {};
+    const sloppyGlobals = true;
 
     const safeEval = createSafeEvaluatorWhichTakesEndowments(
       createSafeEvaluatorFactory(
@@ -103,21 +103,22 @@ test('createSafeEvaluatorWhichTakesEndowments - options.sloppyGlobals', t => {
 
     // Evaluate normally.
     t.equal(safeEval('abc', { abc: 123 }), 123, 'endowment eval');
-    t.throws(
-      () => safeEval('def', { abc: 123 }),
-      ReferenceError,
-      'no such sloppy global'
-    );
-    t.assert(!('def' in sloppyGlobals), 'sloppy global does not yet exist');
+    t.equal(safeEval('typeof def', { abc: 123 }), 'undefined', 'typeof works');
+
+    // FIXME: We can't have both typeof work and a reference error if no such global.
+    t.equal(safeEval('def', { abc: 123 }), undefined, 'no such global');
+
+    t.assert(!('def' in safeGlobal), 'global does not yet exist');
     t.equal(
       safeEval('def = abc + 333', { abc: 123 }),
       456,
-      'sloppy global assignment'
+      'sloppy global assignment works'
     );
-    t.equal(safeEval('def', { abc: 123 }), 456, 'sloppy global persists');
-    t.equal(sloppyGlobals.def, 456, 'sloppy global uses our object');
+
+    t.equal(safeEval('def', { abc: 123 }), 456, 'assigned global persists');
+    t.equal(safeGlobal.def, 456, 'assigned global uses our safeGlobal');
   } catch (e) {
-    t.isNot(e, e);
+    t.isNot(e, e, 'unexpected exception');
   } finally {
     // eslint-disable-next-line no-proto
     Function.__proto__.constructor.restore();

test/module/scopeHandler.js

@@ -2,7 +2,7 @@ import test from 'tape';
 import sinon from 'sinon';
 import { createScopeHandler } from '../../src/scopeHandler';
 
-test('scope hander traps', t => {
+test('scope handler traps', t => {
   t.plan(13);
 
   sinon.stub(console, 'error').callsFake();
@@ -31,7 +31,7 @@ test('scope hander traps', t => {
   console.error.restore();
 });
 
-test('scope hander has', t => {
+test('scope handler has', t => {
   t.plan(9);
 
   const unsafeGlobal = { foo: {} };
@@ -53,7 +53,7 @@ test('scope hander has', t => {
   t.equal(handler.has(target, 'dummy'), false);
 });
 
-test('scope hander get', t => {
+test('scope handler get', t => {
   t.plan(13);
 
   const unsafeGlobal = { foo: {} };
@@ -81,7 +81,7 @@ test('scope hander get', t => {
   t.equal(handler.get(target, 'dummy'), undefined);
 });
 
-test('scope hander et', t => {
+test('scope handler set', t => {
   t.plan(4);
 
   const unsafeGlobal = {};