# CLI

> Every flag of the tidy command, what it does, and the exit codes it returns.

```sh
$ tidy [paths...] [options]          # print the formatted file
$ tidy up [paths...] [options]       # rewrite files in place
$ tidy check [paths...] [options]    # list what isn't formatted
```

```sh
# print one file, formatted
$ tidy index.html

# list the files that aren't formatted; exits 1 if any
$ tidy check src

# rewrite everything in place
$ tidy up .

# a different width for one run
$ tidy up . --width 100
```

## Commands

| Command      | What it does                                                                                    |
| ------------ | ----------------------------------------------------------------------------------------------- |
| `tidy`       | Print the formatted result to stdout.                                                           |
| `tidy up`    | Rewrite each file in place, and print what it rewrote. Files already formatted are not touched. |
| `tidy check` | Print the paths that are not formatted. Changes nothing. Exits 1 if any.                        |

Bare `tidy` reads stdin when it gets no paths, and takes one file otherwise. `up` and `check` take as many paths as you like, and the current folder when you give none.

```sh
$ tidy check          # the same as: tidy check .
$ cat a.ts | tidy --stdin-filepath a.ts
```

A folder named `up` or `check` is read as the command, not as a path. Write `./up` to mean the folder.

## Only what git says changed

Instead of naming paths, let git name them. Both work with `up` and `check`, and not with bare `tidy`.

| Flag                | What it does                                                                                                 |
| ------------------- | ------------------------------------------------------------------------------------------------------------ |
| `--staged`          | Only files staged in the index. `tidy up` stages what it rewrote, so the commit holds the formatted version. |
| `--changed[=<ref>]` | Only files that differ from a branch or commit. Without a value, the default branch.                         |

```sh
# a pre-commit hook, in one line
$ tidy up --staged

# everything this branch touched
$ tidy check --changed

# against a named branch or commit
$ tidy check --changed=main
$ tidy check --changed=HEAD~3
```

`--changed` compares the working tree against the merge base of the ref and `HEAD`, so it covers what you committed on this branch _and_ what you have not committed yet. New files that git does not track yet are included; files a `.gitignore` covers are not.

The default branch is `origin/HEAD` where that is set, else `main`, else `master`. If none of those exist, name the ref yourself.

A path narrows what git named, rather than adding to it:

```sh
# only the changed files under src/
$ tidy check --changed=main src
```

When git names no file tidy can format, the run succeeds and prints nothing — a commit that touches no formattable file is not a failure.

`--changed` takes its value with `=`, because `--changed main` cannot be told apart from `--changed` followed by the path `main`.

## Choosing files

| Flag                      | What it does                                                                                    |
| ------------------------- | ----------------------------------------------------------------------------------------------- |
| `--parser <name>`         | Force a language instead of guessing from the file name.                                        |
| `--stdin-filepath <path>` | The path the text on stdin would have, which decides its language and which config files apply. |
| `--threads <n>`           | How many files to format at once. Defaults to one per core; `1` uses a single thread.           |

`--parser` takes `html`, `vue`, `mjml`, `handlebars`, `tempura`, `css`, `scss`, `less`, `json`, `jsonc`, `json5`, `json-stringify`, `yaml`, `toml`, `dockerfile`, `ini`, `gitconfig`, `graphql`, `babel`, `typescript`, `babel-ts`, `xml` or `markdown`. The names are Prettier's.

When tidy walks a folder it skips `node_modules` and every folder whose name starts with `.`. It does not read `.gitignore`. To leave other paths out, pass the paths you do want, or see [Ignoring code](/docs/ignore/).

## Config

| Flag              | What it does                                                |
| ----------------- | ----------------------------------------------------------- |
| `--config <path>` | Use this config for every file, instead of the nearest one. |
| `--no-config`     | Read no config files, and no `.editorconfig`.               |

Without either, each file takes the nearest `tidy.json`, `tidy.jsonc` or `tidy.toml`, on top of any `.editorconfig` that applies. Options given on the command line override both. See [Configuration file](/docs/configuration/).

## Style

Every one of these has a config equivalent, documented in [Options](/docs/options/).

| Flag                          | Default           | What it does                                                                 |
| ----------------------------- | ----------------- | ---------------------------------------------------------------------------- |
| `--width <n>`                 | `80`              | The line width the printer fits to. `120` for Dockerfiles.                   |
| `--indent <n>`                | `2`               | The width of one indent.                                                     |
| `--tabs`                      | off               | Indent with tabs.                                                            |
| `--eol <eol>`                 | `lf`              | Line endings: `lf`, `crlf` or `cr`.                                          |
| `--whitespace <how>`          | `auto`            | HTML whitespace sensitivity: `strict`, `auto` or `ignore`. `strict` for XML. |
| `--quote <quote>`             | `double`          | Quotes in Handlebars, style sheets, JSON5, YAML and JS.                      |
| `--no-trailing-comma`         |                   | No trailing commas in SCSS, JSONC, JSON5, YAML, TOML and JS.                 |
| `--no-bracket-spacing`        |                   | No spaces inside the braces of JSON and JS objects, and YAML flow mappings.  |
| `--single-attribute-per-line` | off               | Put each attribute on its own line.                                          |
| `--bracket-same-line`         | off               | Keep the `>` of a multi-line tag on the last line.                           |
| `--ignore <name>`             | `prettier-ignore` | The name of the ignore directive.                                            |
| `--no-embedded`               |                   | Leave code of other languages inside a file as it is written.                |

## Other

| Flag              | What it does       |
| ----------------- | ------------------ |
| `-v`, `--version` | Print the version. |
| `-h`, `--help`    | Print help.        |

## Exit codes

| Code | Means                                                                                       |
| ---- | ------------------------------------------------------------------------------------------- |
| `0`  | Success. With `check`, every file is formatted.                                             |
| `1`  | With `check`, at least one file is not formatted.                                           |
| `2`  | Something failed: a file would not parse, a path could not be read, or an option was wrong. |

A `check` run that cannot parse a file exits `2`, not `1`, so a broken file is never reported as merely unformatted.

## stdin

```sh
$ cat index.html | tidy --stdin-filepath index.html
$ echo '{"a":1}' | tidy --parser json
```

Without `--stdin-filepath` or `--parser`, tidy treats stdin as HTML. `--stdin-filepath` is the better of the two, because it also decides which config files apply.