v8/test/cctest/test-usecounters.cc
Adam Klein 946f78a0ad [parsing] Add a UseCounter for labeled expression statements
This was suggested by bmeurer after running into the confusing
example of:

  x => {x:x}

which might appear to be an arrow function that returns an object
literal containing its argument, but instead is an arrow function
that does nothing.

While it's unclear whether the language would change to make this
probable programmer error an actual syntax error, we can at least
gather some data on the question of whether we see any such code
in the wild.

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I08202039ecf7a7a4c71ad95ecd839436b4ec2af8
Reviewed-on: https://chromium-review.googlesource.com/600888
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47171}
2017-08-04 18:51:54 +00:00

143 lines
5.9 KiB
C++

// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/v8.h"
#include "test/cctest/cctest.h"
namespace {
int* global_use_counts = NULL;
void MockUseCounterCallback(v8::Isolate* isolate,
v8::Isolate::UseCounterFeature feature) {
++global_use_counts[feature];
}
}
TEST(DefineGetterSetterThrowUseCount) {
i::FLAG_harmony_strict_legacy_accessor_builtins = false;
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
LocalContext env;
int use_counts[v8::Isolate::kUseCounterFeatureCount] = {};
global_use_counts = use_counts;
CcTest::isolate()->SetUseCounterCallback(MockUseCounterCallback);
// __defineGetter__ and __defineSetter__ do not increment
// kDefineGetterOrSetterWouldThrow on success
CompileRun(
"var a = {};"
"Object.defineProperty(a, 'b', { value: 0, configurable: true });"
"a.__defineGetter__('b', ()=>{});");
CHECK_EQ(0, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
CompileRun(
"var a = {};"
"Object.defineProperty(a, 'b', { value: 0, configurable: true });"
"a.__defineSetter__('b', ()=>{});");
CHECK_EQ(0, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
// __defineGetter__ and __defineSetter__ do not increment
// kDefineGetterOrSetterWouldThrow on other errors
v8::Local<v8::Value> resultProxyThrow = CompileRun(
"var exception;"
"try {"
"var a = new Proxy({}, { defineProperty: ()=>{throw new Error;} });"
"a.__defineGetter__('b', ()=>{});"
"} catch (e) { exception = e; }"
"exception");
CHECK_EQ(0, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
CHECK(resultProxyThrow->IsObject());
resultProxyThrow = CompileRun(
"var exception;"
"try {"
"var a = new Proxy({}, { defineProperty: ()=>{throw new Error;} });"
"a.__defineSetter__('b', ()=>{});"
"} catch (e) { exception = e; }"
"exception");
CHECK_EQ(0, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
CHECK(resultProxyThrow->IsObject());
// __defineGetter__ and __defineSetter__ increment
// kDefineGetterOrSetterWouldThrow when they would throw per spec (B.2.2.2)
CompileRun(
"var a = {};"
"Object.defineProperty(a, 'b', { value: 0, configurable: false });"
"a.__defineGetter__('b', ()=>{});");
CHECK_EQ(1, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
CompileRun(
"var a = {};"
"Object.defineProperty(a, 'b', { value: 0, configurable: false });"
"a.__defineSetter__('b', ()=>{});");
CHECK_EQ(2, use_counts[v8::Isolate::kDefineGetterOrSetterWouldThrow]);
}
TEST(AssigmentExpressionLHSIsCall) {
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
LocalContext env;
int use_counts[v8::Isolate::kUseCounterFeatureCount] = {};
global_use_counts = use_counts;
CcTest::isolate()->SetUseCounterCallback(MockUseCounterCallback);
// AssignmentExpressions whose LHS is not a call do not increment counters
CompileRun("function f(){ a = 0; a()[b] = 0; }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
CompileRun("function f(){ ++a; ++a()[b]; }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
CompileRun("function f(){ 'use strict'; a = 0; a()[b] = 0; }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
CompileRun("function f(){ 'use strict'; ++a; ++a()[b]; }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
// AssignmentExpressions whose LHS is a call increment appropriate counters
CompileRun("function f(){ a() = 0; }");
CHECK_NE(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy] = 0;
CompileRun("function f(){ 'use strict'; a() = 0; }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_NE(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict] = 0;
// UpdateExpressions whose LHS is a call increment appropriate counters
CompileRun("function f(){ ++a(); }");
CHECK_NE(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy] = 0;
CompileRun("function f(){ 'use strict'; ++a(); }");
CHECK_EQ(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInSloppy]);
CHECK_NE(0, use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict]);
use_counts[v8::Isolate::kAssigmentExpressionLHSIsCallInStrict] = 0;
}
TEST(LabeledExpressionStatement) {
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
LocalContext env;
int use_counts[v8::Isolate::kUseCounterFeatureCount] = {};
global_use_counts = use_counts;
CcTest::isolate()->SetUseCounterCallback(MockUseCounterCallback);
CompileRun("typeof a");
CHECK_EQ(0, use_counts[v8::Isolate::kLabeledExpressionStatement]);
CompileRun("foo: null");
CHECK_EQ(1, use_counts[v8::Isolate::kLabeledExpressionStatement]);
CompileRun("foo: bar: baz: undefined");
CHECK_EQ(2, use_counts[v8::Isolate::kLabeledExpressionStatement]);
CompileRun(
"foo: if (false);"
"bar: { }"
"baz: switch (false) { }"
"bat: do { } while (false);");
CHECK_EQ(2, use_counts[v8::Isolate::kLabeledExpressionStatement]);
}