Vitest Coverage v8 & Istanbul Providers Broken

[lishaduck]

Relates to #23882.
Version: Deno 2.1.1

The v8 provider returns 0 for everything.
The istanbul provider is just wrong:

I think instanbul is mostly just mapping the line #s wrong, but it generally looks accurate-ish.

[marvinhagemeister]

Looks like something is different in the inspector. On Deno I get these coverage lines:

[
  // ...
  {
    scriptId: '406',
    url: '/Users/marvinh/dev/test/deno-vitest-cov2/src/foo.test.js',
    functions: [ [Object], [Object], [Object] ]
  },
  {
    scriptId: '408',
    url: '/Users/marvinh/dev/test/deno-vitest-cov2/src/foo.ts',
    functions: [ [Object], [Object], [Object], [Object] ]
  }
]

Whereas in Node I get this:

[
  // ...
  {
    scriptId: '265',
    url: 'file:///Users/marvinh/dev/test/deno-vitest-cov2/src/foo.test.js',
    functions: [ [Object], [Object], [Object] ]
  },
  {
    scriptId: '267',
    url: 'file:///Users/marvinh/dev/test/deno-vitest-cov2/src/foo.ts',
    functions: [ [Object], [Object], [Object], [Object] ]
  }
]

This is problematic because vitest filters out anything that doesn't start with file:// here https://github.com/vitest-dev/vitest/blob/021944cd588958f3fa22d632e2bfd3efa0f1310d/packages/coverage-v8/src/index.ts#L20-L34

session.post("Profiler.takePreciseCoverage", async (error, coverage) => {
  //...
  const result = coverage.result.filter(filterResult);
  resolve({ result });
});

function filterResult(coverage) {
  if (!coverage.url.startsWith("file://")) {
    return false;
  }
  if (coverage.url.includes("/node_modules/")) {
    return false;
  }
  return true;
}

I wasn't able to isolate it further as just doing the inspector stuff leads to the correct script urls being printed. Not sure why they are stripped with vitest.

Steps to reproduce

1. Clone https://github.com/marvinhagemeister/deno-vitest-cov2
2. Run deno install
3. Run deno task test

[yasaichi]

@marvinhagemeister
Any updates on this? This would be the last blocker when trying to use Vitest with Deno in production-grade applications.

[AriPerkkio]

While looking into issue on Vitest side (vitest-dev/vitest#7660), noticed that this minimal reproduction works on Node but not on Deno. Should Profiler.takePreciseCoverage and Profiler.startPreciseCoverage be supported? This is on deno 2.2.3:

import inspector from "node:inspector";

function firstMethod() {}

const session = new inspector.Session();
session.connect();
session.post("Profiler.enable");
session.post("Profiler.startPreciseCoverage", { callCount: true, detailed: true });

firstMethod();

const coverage = await new Promise((resolve, reject) => {
  session.post("Profiler.takePreciseCoverage", async (error, coverage) => {
    if (error) return reject(error);
    resolve(coverage.result.filter((entry) => !entry.url.startsWith("node:")));
  });
});

console.log(JSON.stringify(coverage, null, 2));

$ deno -v; deno --allow-sys ./coverage.mjs 
deno 2.2.3
[]

$ node -v; node ./coverage.mjs 
v22.14.0
[
  {
    "scriptId": "94",
    "url": "file:///Users/x/coverage.mjs",
    "functions": [
      {
        "functionName": "firstMethod",
        "ranges": [
          {
            "startOffset": 41,
            "endOffset": 66,
            "count": 1
          }
        ],
        "isBlockCoverage": true
      },
      {
        "functionName": "coverage",
        "ranges": [
          {
            "startOffset": 297,
            "endOffset": 520,
            "count": 1
          }
        ],
        "isBlockCoverage": true
      },
      {
        "functionName": "",
        "ranges": [
          {
            "startOffset": 367,
            "endOffset": 516,
            "count": 0
          }
        ],
        "isBlockCoverage": false
      }
    ]
  }
]