dirstat

Fast, single-binary directory statistics CLI: every file under a tree grouped by format, with counts, sizes, and lines of code, as a colored terminal table or as JSON.

It is built for developers and agents sizing up an unfamiliar repository, and for tooling that wants the same numbers as a machine-readable document. Every classification list and format alias table is compiled into one static binary, so a scan spawns no subprocesses, reads no configuration file it was not explicitly handed, and classifies files across a worker pool.

Quick start

go install github.com/smm-h/dirstat@latest

Summarize the current directory:

dirstat scan

Summarize a project, machine output for tooling:

dirstat scan ~/src/myproject --json

Example

$ dirstat scan .

Summary
──────────────────────────────────────────────────
  Directories: 31
  Files: 60
  Files without extension: 17
  Max depth: 5
  Symlinks (skipped): 0
  Executables: 14
  Unique formats: 11
  Files sniffed: 17
  Unreadable (skipped): 0

Files by Format
──────────────────────────────────────────────────
┌────────┬───────┬────────────┬───────────┬─────────┐
│ Format │ Count │ Total Size │ Total LOC │ ...     │
├────────┼───────┼────────────┼───────────┼─────────┤
│ go     │ 21    │ 79.6KB     │ 2,893     │ ...     │
│ md     │ 1     │ 13.1KB     │ 232       │ ...     │
└────────┴───────┴────────────┴───────────┴─────────┘

Commands

Command	Description
scan	Summarize the files under a directory tree, grouped by format, with counts, sizes, and lines of code as terminal tables or JSON.

Every flag is documented in dirstat scan --help and in the generated .stricttools/docs/cli-scan.md.

Grouping methods

Method	Behavior
ext	Group by file extension only; text/binary decided by an embedded extension list; no content sniffing
type	Content-sniff every file; group by detected MIME type
hybrid (default)	Files with an extension behave as in ext; extensionless files are sniffed and grouped by MIME type

Format names

--formats decides how the group name the method chose is spelled. It changes no verdict: the same files are read, sniffed and classified either way.

Mode	Behavior
raw (default)	The extension or sniffed MIME type verbatim, so a.mjs and b.js are separate groups and an extensionless script counts under text/plain
canonical	Alias formats merge (mjs/cjs into js, h into c, hpp into cpp, text/x-python into py), and an extensionless file with a shebang is named by its interpreter (#!/usr/bin/env -S uv run python counts under py)

The alias table is embedded from internal/config/data/canonical_formats.txt. The shebang reader strips an env wrapper (including its -S form and NAME=value assignments), resolves the uv run X and uvx X runner forms, and drops a trailing version (python3.12 reads as python); an interpreter it does not know falls through to content sniffing.

Configuration

dirstat scan --config <path> reads scan defaults from a TOML file. There is no default config path and no auto-discovery — dirstat never picks up config from XDG, HOME, the current directory, or the scanned tree; the file is used only when --config is passed.

Allowed keys are exactly the scan-semantic flags (names with underscores): exclude, method, formats, depth, ignored, hidden, type, stats, sort_by, sort_order. Rendering and output options (colors, style, output, top, ...) cannot be set from a file. Values are validated up front with the same rules as the flags; any unknown key, wrong type, or invalid value is a hard error before scanning starts.

A key may come from the file or from the command line, never both: setting a key in the file and also passing its flag is a hard error, so there is no silent override. Flags for keys the file does not set remain usable alongside --config.

# scan.toml
exclude = ["node_modules", ".git", "dist"]  # replaces the built-in default list
method = "ext"
formats = "canonical"
depth = 3
stats = ["count", "total-size"]

By default --exclude uses a curated built-in list (.git, node_modules, .venv, vendor, build, dist, target, and other common cache/IDE directories — see dirstat scan --help). Any explicit --exclude or a config-file exclude key replaces the list entirely; exclude = [] scans everything.

Machine output

--json is strictcli's machine mode: stdout carries exactly one document, the framework's envelope, and the scan document is its payload member. No ANSI codes, raw integer values, and no table. The payload's shape is a consumer contract — field names are stable, evolution is additive-only, and the command declares the shape as a JSON Schema the framework validates before writing it.

{
  "interface_version": 1,
  "app": "dirstat",
  "app_version": "0.1.0",
  "command": "scan",
  "exit_code": 0,
  "payload": {
    "root": "/abs/path",
    "method": "hybrid",
    "summary": {
      "directories": 3, "files": 6, "files_without_extension": 1,
      "max_depth": 2, "symlinks": 0, "executables": 0,
      "unique_formats": 5, "files_sniffed": 1, "unreadable": 0
    },
    "groups": [
      {
        "format": "go", "text": true, "count": 2,
        "total_size": 39, "min_size": 10, "max_size": 29, "avg_size": 20,
        "total_loc": 4, "min_loc": 1, "max_loc": 3, "avg_loc": 2
      }
    ],
    "no_extension_files": ["Makefile"]
  },
  "dry_run": false,
  "preview": [],
  "preview_error": null,
  "diagnostics": []
}

LOC fields are null for binary groups. Stats absent from --stats are omitted. no_extension_files is present only with --list-no-ext. The binary's version is the envelope's app_version and is not repeated inside the payload.

Behavior notes

• Rendering-only flags (--show, --combined, --singletons, --legend, --colors, --human, --style, --top) have no effect on the machine payload.
• Without active colors (piped output or --no-colors), the table width is pinned to 80 columns so the output is byte-identical to non-TTY output.
• Symlinks are never followed, but every symlink encountered in a traversed directory is counted.
• Unreadable directories and files are skipped and counted under Unreadable (skipped) — never a warning spew, never a crash.
• Gitignore matching is fully in-process (no git subprocess): patterns come from every .gitignore in the work tree, .git/info/exclude, and the global core.excludesFile. Outside a git work tree, --ignored exclude/only behave as if no patterns exist.
• LOC counting is skipped entirely (no file reads) unless a LOC stat is selected or sorted by.
• The text-extension and text-mimetype lists and both color themes are embedded in the binary; there are no runtime config files.