v8/test/mjsunit/code-coverage-utils.js

// Copyright 2017 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.

// Flags: --allow-natives-syntax

let TestCoverage;
let TestCoverageNoGC;

let nop;
let gen;

!function() {
  function GetCoverage(source) {
    for (var script of %DebugCollectCoverage()) {
      if (script.script === source) return script;
    }
    return undefined;
  };

  function TestCoverageInternal(name, source, expectation, collect_garbage) {
    source = source.trim();
    eval(source);
    if (collect_garbage) %CollectGarbage("collect dead objects");
    var covfefe = GetCoverage(source);
    var stringified_result = JSON.stringify(covfefe);
    var stringified_expectation = JSON.stringify(expectation);
    if (stringified_result != stringified_expectation) {
      print(stringified_result.replace(/[}],[{]/g, "},\n {"));
    }
    assertEquals(stringified_expectation, stringified_result, name + " failed");
  };

  TestCoverage = function(name, source, expectation) {
    TestCoverageInternal(name, source, expectation, true);
  };

  TestCoverageNoGC = function(name, source, expectation) {
    TestCoverageInternal(name, source, expectation, false);
  };

  nop = function() {};

  gen = function*() {
    yield 1;
    yield 2;
    yield 3;
  };
}();