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comparison: js/src/tests/ecma_6/Proxy/proxy-isExtensible.js
js/src/tests/ecma_6/Proxy/proxy-isExtensible.js
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
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| -1:000000000000 | 0:20835ff7b31f |
|---|---|
| 1 // Test ES6 Proxy trap compliance for Object.isExtensible() on exotic proxy | |
| 2 // objects. | |
| 3 var unsealed = {}; | |
| 4 var sealed = Object.seal({}); | |
| 5 var handler = {}; | |
| 6 | |
| 7 assertEq(Object.isExtensible(unsealed), true); | |
| 8 assertEq(Object.isExtensible(sealed), false); | |
| 9 | |
| 10 var targetSealed = new Proxy(sealed, handler); | |
| 11 var targetUnsealed = new Proxy(unsealed, handler); | |
| 12 | |
| 13 var handlerCalled = false; | |
| 14 | |
| 15 // without traps, forward to the target | |
| 16 // First, make sure we get the obvious answer on a non-exotic target. | |
| 17 assertEq(Object.isExtensible(targetSealed), false, "Must forward to target without hook."); | |
| 18 assertEq(Object.isExtensible(targetUnsealed), true, "Must forward to target without hook."); | |
| 19 | |
| 20 // Now, keep everyone honest. What if the target itself is a proxy? | |
| 21 function ensureCalled() { handlerCalled = true; return true; } | |
| 22 var proxyTarget = new Proxy({}, { isExtensible : ensureCalled }); | |
| 23 assertEq(Object.isExtensible(new Proxy(proxyTarget, {})), true, "Must forward to target without hook."); | |
| 24 assertEq(handlerCalled, true, "Must forward to target without hook."); | |
| 25 | |
| 26 // with traps, makes sure that the handler is called, and that we throw if the | |
| 27 // trap disagrees with the target | |
| 28 function testExtensible(obj, shouldThrow, expectedResult) | |
| 29 { | |
| 30 handlerCalled = false; | |
| 31 if (shouldThrow) | |
| 32 assertThrowsInstanceOf(function () { Object.isExtensible(obj); }, | |
| 33 TypeError, "Must throw if handler and target disagree."); | |
| 34 else | |
| 35 assertEq(Object.isExtensible(obj), expectedResult, "Must return the correct value."); | |
| 36 assertEq(handlerCalled, true, "Must call handler trap if present"); | |
| 37 } | |
| 38 | |
| 39 // What if the trap says it's necessarily sealed? | |
| 40 function fakeSealed() { handlerCalled = true; return false; } | |
| 41 handler.isExtensible = fakeSealed; | |
| 42 testExtensible(targetSealed, false, false); | |
| 43 testExtensible(targetUnsealed, true); | |
| 44 | |
| 45 // What if the trap says it's never sealed? | |
| 46 function fakeUnsealed() { handlerCalled = true; return true; } | |
| 47 handler.isExtensible = fakeUnsealed; | |
| 48 testExtensible(targetSealed, true); | |
| 49 testExtensible(targetUnsealed, false, true); | |
| 50 | |
| 51 // make sure we are able to prevent further extensions mid-flight and throw if the | |
| 52 // hook tries to lie. | |
| 53 function makeSealedTruth(target) { handlerCalled = true; Object.preventExtensions(target); return false; } | |
| 54 function makeSealedLie(target) { handlerCalled = true; Object.preventExtensions(target); return true; } | |
| 55 handler.isExtensible = makeSealedTruth; | |
| 56 testExtensible(new Proxy({}, handler), false, false); | |
| 57 handler.isExtensible = makeSealedLie; | |
| 58 testExtensible(new Proxy({}, handler), true); | |
| 59 | |
| 60 // What if the trap doesn't directly return a boolean? | |
| 61 function falseyNonBool() { handlerCalled = true; return undefined; } | |
| 62 handler.isExtensible = falseyNonBool; | |
| 63 testExtensible(targetSealed, false, false); | |
| 64 testExtensible(targetUnsealed, true); | |
| 65 | |
| 66 function truthyNonBool() { handlerCalled = true; return {}; } | |
| 67 handler.isExtensible = truthyNonBool; | |
| 68 testExtensible(targetSealed, true); | |
| 69 testExtensible(targetUnsealed, false, true); | |
| 70 | |
| 71 // What if the trap throws? | |
| 72 function ExtensibleError() { } | |
| 73 ExtensibleError.prototype = new Error(); | |
| 74 ExtensibleError.prototype.constructor = ExtensibleError; | |
| 75 function throwFromTrap() { throw new ExtensibleError(); } | |
| 76 handler.isExtensible = throwFromTrap; | |
| 77 | |
| 78 // exercise some other code paths and make sure that they invoke the trap and | |
| 79 // can handle the ensuing error. | |
| 80 assertThrowsInstanceOf(function () { Object.isExtensible(targetSealed); }, | |
| 81 ExtensibleError, "Must throw if the trap does."); | |
| 82 assertThrowsInstanceOf(function () { Object.isFrozen(targetSealed); }, | |
| 83 ExtensibleError, "Must throw if the trap does."); | |
| 84 assertThrowsInstanceOf(function () { Object.isSealed(targetSealed); }, | |
| 85 ExtensibleError, "Must throw if the trap does."); | |
| 86 | |
| 87 | |
| 88 // What if the trap likes to re-ask old questions? | |
| 89 function recurse() { return Object.isExtensible(targetSealed); } | |
| 90 handler.isExtensible = recurse; | |
| 91 assertThrowsInstanceOf(function () { Object.isExtensible(targetSealed); }, | |
| 92 InternalError, "Should allow and detect infinite recurison."); | |
| 93 | |
| 94 reportCompare(0, 0, "OK"); |
