---
title: The .tap Folder
eleventyNavigation:
  key: .tap Folder
  parent: Docs
  order: 47
---

> _tl;dr_ - Tap puts stuff in `.tap`. It's probably best to
> `.gitignore` this folder.

The `.tap` folder is used to store various things that tap uses.

## `.tap/processinfo`

Every process that is spawned in the course of running tests is
assigned a UUID and information about it is stored for later
analysis. This is used by tap to be able to know which tests need
to be re-run when you do `tap --changed`, for example.

The data is created by
[`@tapjs/processinfo`](https://github.com/tapjs/processinfo).
Each of the files in this folder have a filename corresponding to
the uuid, and contain a JSON-encoded
[`ProcessInfoNodeData`](https://tapjs.github.io/processinfo/interfaces/process_info_node.ProcessInfoNodeData.html)
object.

These nodes have a `root` and `parent` fields, creating a tree
structure of processes. You can explore the tree by using the `i`
command in the [REPL](./repl.md).

```
TAP> i test/config.ts
test/config.ts:
  date: 2023-10-05T22:58:15.094Z
  command: /usr/local/bin/node
  args:
    - --import=file:///Users/isaacs/dev/tapjs/tapjs/node_modules/@tapjs/mock/dist/esm/import.mjs
    - --loader=file:///Users/isaacs/dev/tapjs/tapjs/node_modules/ts-node/esm.mjs
    - --no-warnings
    - --enable-source-maps
    - --import=file:///Users/isaacs/dev/tapjs/tapjs/node_modules/@tapjs/processinfo/dist/esm/import.mjs
    - /Users/isaacs/dev/tapjs/tapjs/src/run/test/config.ts
  cwd: /Users/isaacs/dev/tapjs/tapjs/src/run
  pid: 93041
  ppid: 93003
  code: 0
  runtime: 3737.6802079999998

TAP> i 686a4eb3-e82f-4b6b-b365-2c38195776f9
686a4eb3-e82f-4b6b-b365-2c38195776f9:
  date: 2023-10-05T22:58:31.447Z
  command: /usr/local/bin/node
  args:
    - /Users/isaacs/dev/tapjs/tapjs/src/run/dist/esm/index.js
    - blah.test.js
  cwd: /Users/isaacs/dev/tapjs/tapjs/src/run/.tap/fixtures/test-run.ts-fail-to-find-all-named-test-files
  pid: 93259
  ppid: 93149
  parent: ee929bda-9b80-43af-a5d7-da233c1f80f9
  code: 1
  runtime: 490.024416
```

## `.tap/coverage`

The coverage generated by each test process is stored to this
folder, with a `<uuid>.json` filename corresponding to the file
for the process in `.tap/processinfo`.

These are V8 coverage dump files, with a `source-map-cache`
attached to be able to turn V8's byte-offset-based coverage
reporting into line/column reporting used by the istanbul
reporters.

It's the same format used by the `NODE_V8_COVERAGE` directory,
but limited only to the files in your program that you've opted
to provide coverage for, instead of _everything_ in
`node_modules` and node's built-in modules. You can use this
folder as an argument to any other program that knows how to
interpret this format, or put coverage files in this folder and
tap will include them in its coverage reporting.

## `.tap/report`

When generating coverage reports, the files generated go in here.

| `--coverage-report` config | file generated                                                |
| -------------------------- | ------------------------------------------------------------- |
| `text` (default)           | no file generated, just writes to terminal                    |
| `html`                     | `.tap/report/index.html`                                      |
| `lcov`                     | `.tap/report/lcov.info`, `.tap/report/lcov-report/index.html` |
| `clover`                   | `.tap/report/clover.xml`                                      |
| `cobertura`                | `.tap/report/cobertura-coverage.xml`                          |
| `json`                     | `.tap/report/coverage-final.json                              |
| `json-summary`             | `.tap/report/coverage-summary.json                            |
| `lcovonly`                 | `.tap/report/lcov.info`                                       |

## `.tap/fixtures`

This is the folder where the [`@tapjs/fixture`
plugin](./plugins/fixture.md) puts its test fixture files.

## `.tap/test-results`

Whenever tests are run, the [raw TAP](./tap-format.md) output is
saved to this folder. This is what the [`tap
replay`](./cli.11ty.js#tap-replay) command uses to replay the
results of the previous test run.

## Ignoring or Saving

There's little harm in exposing the `.tap` folder, as the only
sensitive data it typically contains (other than your code
itself) is file and folder paths.

However, becuase it _does_ contain file and folder paths, it's
system specific, and generally not something you'd want to check
into source control, so I recommend adding `/.tap` to your
`.gitignore` file.
