Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1 | // Copyright 2016 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | // Flags: --harmony-async-await |
| 6 | // Flags: --expose-debug-as debug --allow-natives-syntax --ignition-generators |
| 7 | |
| 8 | var Debug = debug.Debug; |
| 9 | var LiveEdit = Debug.LiveEdit; |
| 10 | |
| 11 | unique_id = 0; |
| 12 | |
| 13 | var AsyncFunction = (async function(){}).constructor; |
| 14 | |
| 15 | function assertPromiseValue(value, promise) { |
| 16 | promise.then(resolve => { |
| 17 | went = true; |
| 18 | if (resolve !== value) { |
| 19 | print(`expected ${value} found ${resolve}`); |
| 20 | quit(1); |
| 21 | } |
| 22 | }, reject => { |
| 23 | print(`rejected ${reject}`); |
| 24 | quit(1); |
| 25 | }); |
| 26 | } |
| 27 | |
| 28 | function MakeAsyncFunction() { |
| 29 | // Prevents eval script caching. |
| 30 | unique_id++; |
| 31 | return AsyncFunction('callback', |
| 32 | "/* " + unique_id + "*/\n" + |
| 33 | "await callback();\n" + |
| 34 | "return 'Cat';\n"); |
| 35 | } |
| 36 | |
| 37 | function MakeFunction() { |
| 38 | // Prevents eval script caching. |
| 39 | unique_id++; |
| 40 | return Function('callback', |
| 41 | "/* " + unique_id + "*/\n" + |
| 42 | "callback();\n" + |
| 43 | "return 'Cat';\n"); |
| 44 | } |
| 45 | |
| 46 | // First, try MakeGenerator with no perturbations. |
| 47 | (function(){ |
| 48 | var asyncfn = MakeAsyncFunction(); |
| 49 | function callback() {}; |
| 50 | var promise = asyncfn(callback); |
| 51 | assertPromiseValue('Cat', promise); |
| 52 | })(); |
| 53 | |
| 54 | function patch(fun, from, to) { |
| 55 | function debug() { |
| 56 | var log = new Array(); |
| 57 | var script = Debug.findScript(fun); |
| 58 | var pos = script.source.indexOf(from); |
| 59 | print(`pos ${pos}`); |
| 60 | try { |
| 61 | LiveEdit.TestApi.ApplySingleChunkPatch(script, pos, from.length, to, |
| 62 | log); |
| 63 | } finally { |
| 64 | print("Change log: " + JSON.stringify(log) + "\n"); |
| 65 | } |
| 66 | } |
| 67 | %ExecuteInDebugContext(debug); |
| 68 | } |
| 69 | |
| 70 | // Try to edit a MakeAsyncFunction while it's running, then again while it's |
| 71 | // stopped. |
| 72 | (function(){ |
| 73 | var asyncfn = MakeAsyncFunction(); |
| 74 | |
| 75 | var patch_attempted = false; |
| 76 | function attempt_patch() { |
| 77 | assertFalse(patch_attempted); |
| 78 | patch_attempted = true; |
| 79 | assertThrows(function() { patch(asyncfn, "'Cat'", "'Capybara'") }, |
| 80 | LiveEdit.Failure); |
| 81 | }; |
| 82 | var promise = asyncfn(attempt_patch); |
| 83 | // Patch should not succeed because there is a live async function activation |
| 84 | // on the stack. |
| 85 | assertPromiseValue("Cat", promise); |
| 86 | assertTrue(patch_attempted); |
| 87 | |
| 88 | %RunMicrotasks(); |
| 89 | |
| 90 | // At this point one iterator is live, but closed, so the patch will succeed. |
| 91 | patch(asyncfn, "'Cat'", "'Capybara'"); |
| 92 | promise = asyncfn(function(){}); |
| 93 | // Patch successful. |
| 94 | assertPromiseValue("Capybara", promise); |
| 95 | |
| 96 | // Patching will fail however when an async function is suspended. |
| 97 | var resolve; |
| 98 | promise = asyncfn(function(){return new Promise(function(r){resolve = r})}); |
| 99 | assertThrows(function() { patch(asyncfn, "'Capybara'", "'Tapir'") }, |
| 100 | LiveEdit.Failure); |
| 101 | resolve(); |
| 102 | assertPromiseValue("Capybara", promise); |
| 103 | |
| 104 | // Try to patch functions with activations inside and outside async |
| 105 | // function activations. We should succeed in the former case, but not in the |
| 106 | // latter. |
| 107 | var fun_outside = MakeFunction(); |
| 108 | var fun_inside = MakeFunction(); |
| 109 | var fun_patch_attempted = false; |
| 110 | var fun_patch_restarted = false; |
| 111 | function attempt_fun_patches() { |
| 112 | if (fun_patch_attempted) { |
| 113 | assertFalse(fun_patch_restarted); |
| 114 | fun_patch_restarted = true; |
| 115 | return; |
| 116 | } |
| 117 | fun_patch_attempted = true; |
| 118 | // Patching outside an async function activation must fail. |
| 119 | assertThrows(function() { patch(fun_outside, "'Cat'", "'Cobra'") }, |
| 120 | LiveEdit.Failure); |
| 121 | // Patching inside an async function activation may succeed. |
| 122 | patch(fun_inside, "'Cat'", "'Koala'"); |
| 123 | } |
| 124 | promise = asyncfn(function() { return fun_inside(attempt_fun_patches) }); |
| 125 | assertEquals('Cat', |
| 126 | fun_outside(function () { |
| 127 | assertPromiseValue('Capybara', promise); |
| 128 | assertTrue(fun_patch_restarted); |
| 129 | assertTrue(fun_inside.toString().includes("'Koala'")); |
| 130 | })); |
| 131 | })(); |
| 132 | |
| 133 | %RunMicrotasks(); |