Tests report does not cover exported function from typescript.

[nicolaefilat]

Describe the bug

I have a file called utils.ts in the folder src/logic/utils.ts that has a simple function that adds three numbers.

export function addThreeNumbers(a: number, b: number, c: number) {
    return a + b + c;
}

in the folder src/__tests__/unit/utils.test.ts I have a test for this sum function.

import { describe, it, expect } from 'vitest'
import {addThreeNumbers} from "src/logic/utils";


describe("Sum of three numbers test", () =>{
    it("1 + 2 + 3 = 6",()=>{
        expect(addThreeNumbers(1,2,3)).toBe(6)
    })
})

My vitest.config.ts file looks like this

export default mergeConfig(
    viteConfig,
    defineConfig({
        test: {
            environment: 'jsdom',
            exclude: [...configDefaults.exclude, 'e2e/*'],
            root: fileURLToPath(new URL('./', import.meta.url)),
            coverage: {
                all: true,
                provider: 'c8',
                // move coverage report to ./tests/unit/coverage
                reportsDirectory: './tests/unit/coverage',
                include: ['src/**/*.vue', "src/**/*.ts", "src/**/*.js"],
                exclude: ['src/router', "**/__tests__/**"]
            },
        }
    })
)

I run vitest run --coverage and I see that ✓ src/__tests__/unit/utils.test.ts (1) is ran but
in the report utils.ts has 0 statements covered.

Reproduction

I hope the files provided are enough to see if there is either a bug or I have a misconfiguration somewhere.

System Info

System:
    OS: Windows 10 10.0.22000
    CPU: (16) x64 AMD Ryzen 7 5700U with Radeon Graphics
    Memory: 5.40 GB / 15.35 GB
  Binaries:
    Node: 18.16.0 - C:\Program Files\nodejs\node.EXE
    npm: 9.6.5 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Spartan (44.22000.120.0), Chromium (112.0.1722.58)
    Internet Explorer: 11.0.22000.120

    "vitest": "^0.30.1" (from packages.json)

Used Package Manager

npm

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.

[AriPerkkio]

Could you try removing the test.coverage.include and test.coverage.exclude and see if the file ends up in the report? And maybe even the test.root?

[AriPerkkio]

I can reproduce this now.

When source file is imported using alias the vitenode.fetchCache does not contain full path. This gets filtered out in coverage provider.

import {addThreeNumbers} from "src/logic/utils";
// fetchCache contains entry for "src/logic/utils"

import {addThreeNumbers} from "../../logic/utils";
// fetchCache contains entry for "/x/y/z/repro/src/logic/utils.ts" - Includes the extension and full path

[AriPerkkio]

The vitest.config.ts is missing alias. Add following and coverage report is OK:

    alias: {
      src: fileURLToPath(new URL("./src", import.meta.url)),
    }

Or as alternative import the utils.ts with relative path instead of relying on project root:

- import {addThreeNumbers} from "src/logic/utils";
+ import {addThreeNumbers} from "../../logic/utils";