demurgos

Merge

This document describes the merge algorithm.

The merge algorithm takes a list of process coverages (or smaller items) and outputs a single object combining the information in the inputs. The goal is to simulate the result V8 would have returned if the coverages were executed sequentially inside the same process instead of their own processes (so the counts are summed).

demurgos

  function fromSortedRanges(ranges: ReadonlyArray<RangeCov>): RangeTree | undefined {
    let root: RangeTree | undefined;
    const stack: RangeTree[] = [];
    for (const range of ranges) {
      const node: RangeTree = new RangeTree(range.startOffset, range.endOffset, range.count, [], 0, 0);
      if (root === undefined) {
        root = node;
        stack.push(node);
        continue;
      }

demurgos

 {
    "path": "/data/projects/web/yargs/index.js",
    "statementMap": {
      "0": {
        "start": {
          "line": 1,
          "column": 0
        },
        "end": {
          "line": 1,

demurgos

{
  "scriptId": "1",
  "url": "/test/fixtures/hello-world/lib.js",
  "functions": [
    {
      "functionName": "",
      "ranges": [
        {
          "startOffset": 0,
          "endOffset": 130,

demurgos

export function helloWorld () {
  console.log('Hello, World!')
}

demurgos

[
  "/data/projects/web/v8-to-istanbul/src/test/fixtures/esm-hello-world/main.js",
  "_stream_duplex.js",
  "_stream_passthrough.js",
  "_stream_readable.js",
  "_stream_transform.js",
  "_stream_writable.js",
  "assert.js",
  "buffer.js",
  "cjs-facade:file:///data/projects/web/v8-to-istanbul/src/test/fixtures/esm-hello-world/main.js",

demurgos

{
  "/main.js": {
    "path": "/main.js",
    "statementMap": {
      "s0": {
        "start": {
          "line": 1,
          "column": 0
        },
        "end": {

demurgos

print("Hello, World!")

demurgos

[
  {
    "url": "/main.js",
    "source": "(function (exports, require, module, __filename, __dirname) { require('./timeout')\n\nconsole.info('i am a line of code')\n\nfunction apple (awesome) {\n  if (false || true) {\n    console.info('what')\n  }\n  if (true || false) {\n    console.log('hey')\n  }\n}\n\nfunction missed () {\n  \n}\n\napple()\napple()\napple()\n\n});",
    "functions": [
      {
        "functionName": "",
        "ranges": [
          {
            "startOffset": 0,

demurgos

{
  "/data/projects/various/turbo-gulp/build/test/test.esm.js": {
    "path": "/data/projects/various/turbo-gulp/build/test/test.esm.js",
    "statementMap": {
      "0": {
        "start": {
          "line": 1,
          "column": 0
        },
        "end": {