linecheck 0.3.0

# linecheck

> **Alpha** — experimental, expect breaking changes.

Stop your AI agent from turning one file into a monolith. `linecheck` enforces per-file line limits so bloated files get caught before they pile up.

## Features

- Set per-file or per-glob line limits
- Configurable warn / error thresholds
- Inline ignore comments and config-level excludes
- Works as a CLI, in CI pipelines, and as a library
- Rust core with bindings for npm, pip, Go, and WASM

## Installation

> Bindings are coming soon. The Rust CLI is the first target.

**Rust / Cargo**
```bash
cargo install linecheck
```

**npm**
```bash
npm install -g linecheck
```

**pip**
```bash
pip install linecheck
```

**Go**
```bash
go install github.com/tupe12334/linecheck@latest
```

## Usage

```bash
linecheck [OPTIONS] [FILES...]
```

Check all files in the current directory using your config:
```bash
linecheck .
```

Override the line limit inline:
```bash
linecheck --max-lines 200 src/
```

Example output:
```
src/main.rs: 450 lines (error threshold: 400)
src/utils.rs: 220 lines (warn threshold: 200)
```

See which files are creeping toward their limit before they breach it:
```bash
linecheck --status src/
```
```
src/main.rs:   450 / 400  [ERROR]
src/utils.rs:  220 / 200  [WARN]
src/lib.rs:    180 / 200  90%
src/config.rs:  45 / 200  22%
```

For scripting and CI dashboards, use `--json`:
```bash
linecheck --status --json src/
```

## Presets

Use a preset flag to apply a built-in strictness level without writing a config file:

| Flag        | Max lines  |
| ----------- | ---------- |
| `--strict`  | 100        |
| `--default` | 200        |
| `--loose`   | 400        |
| `--free`    | unlimited  |

```bash
linecheck --strict src/
linecheck --loose .
```

Preset flags are overridden by any `linecheck.yml` in scope.

## Configuration

`linecheck` resolves configuration like `.gitignore` — a `linecheck.yml` applies to its directory and all subdirectories recursively. A nested config overrides the parent for everything inside it. If no config is found anywhere, it falls back to built-in defaults: **warn at 200 lines, error at 400 lines** for all files.

```
project/
├── linecheck.yml        ← applies to everything
└── src/
    ├── linecheck.yml    ← overrides for src/ and below
    └── generated/
        └── linecheck.yml  ← can relax limits for generated code
```

> **Not sure where to start?** 200 lines is a reasonable warn threshold for most source files — it's enough for a focused module but flags anything that's grown too broad.

Create a `linecheck.yml` at the root of your project to override the defaults:

```yaml
rules:
  - pattern: "**/*.rs"
    warn: 200
    error: 400
  - pattern: "**/*.ts"
    warn: 150
    error: 300

exclude:
  - "**/generated/**"
  - "**/vendor/**"
```

When multiple rules match the same file, the most specific pattern wins.

CLI flags override config file values. Run `linecheck --help` for all options.

## Ignoring files

**Exclude globs** — add an `exclude` list to `linecheck.yml` (see above).

**Inline ignore** — add this comment anywhere in the file to exempt it entirely:

```
# linecheck:ignore
```

The file will be skipped regardless of its line count. There is no partial ignore — it's all-or-nothing.

## Exit codes

| Code | Meaning |
| ---- | ------- |
| `0`  | All files within limits (warnings are printed but non-blocking) |
| `1`  | One or more files exceed the error threshold |

## CI examples

See the [`examples/`](examples/) folder for ready-to-use configurations:

- `examples/ci/` — generic CI shell setup
- `examples/github/` — GitHub Actions workflow

## License

[MIT](LICENSE)