CLI reference

The wheel installs a single lessish console script with three subcommands — compile, lint, format — plus version.

$ lessish --version
lessish 0.1.0

$ lessish version
lessish 0.1.0

No security warning on the CLI. The library defaults to the secure file_io='jail', but the CLI stays less.js-compatible: an explicit, interactive invocation reads the filesystem with file_io='allow' and suppresses the LessishSecurityWarning that 'allow' raises on every compile. That warning is reserved for programmatic use, where untrusted Less might reach the compiler — see guide/02-options.md. There is no --file-io flag; lock down reads in Python instead.

---

compile

lessish compile [flags] INPUT

INPUT is a Less file, or - for stdin. Output goes to stdout unless -o is given. Compile defaults come from [tool.lessish] in pyproject.toml (or lessish.toml); flags override per key.

$ lessish compile styles.less
.button {
  color: #4a90d9;
  border: 1px solid #FFFFFF;
  margin: 0px;
}
.button:hover {
  color: #2a76c6;
}

From stdin:

$ printf '.x { c: 1 + 2; }' | lessish compile -
.x {
  c: 3;
}

To a file:

$ lessish compile styles.less -o out.css

Flags

Flag	Effect
-o, --out PATH	Write CSS to PATH (default: stdout).
--config PATH	Compile-config file (default: pyproject.toml).
--compress	Minified output.
--source-map	Emit a Source Maps v3 annotation.
--source-map-out PATH	Write the map JSON to PATH (implies --source-map).
--source-map-url URL	URL embedded in the sourceMappingURL annotation.
--paths DIR	Extra @import search dir (repeatable; extends config).
--math {always,parens-division,parens}	Arithmetic mode (default: parens-division).
--strict-units	Raise on compound-unit arithmetic.
--global-var NAME=VALUE	Inject @NAME: VALUE before user code (repeatable).
--modify-var NAME=VALUE	Inject @NAME: VALUE after user code, overriding it (repeatable).
--no-process-imports	Don't splice @imports (less-shape only).
--rewrite-urls {all,local,off}	Rewrite url(...) in imported files (default: off).
--rootpath PREFIX	Prefix prepended to every url(...).
--url-args SUFFIX	Query-string suffix appended to every url(...).
--banner TEXT	Verbatim prefix for the emitted CSS.

The option semantics match the Python API one-for-one — see guide/02-options.md.

Minify

$ lessish compile styles.less --compress
.button{color:#4a90d9;border:1px solid #FFFFFF;margin:0px}.button:hover{color:#2a76c6}

Inject a variable

$ printf '.a { color: @c; }' | lessish compile - --global-var c=blue
.a {
  color: blue;
}

Source maps

--source-map-out writes both the CSS (with a trailing sourceMappingURL annotation) and the separate map JSON:

$ lessish compile styles.less --source-map-out styles.css.map -o styles.css
$ tail -c 38 styles.css
/*# sourceMappingURL=styles.css.map */

See guide/03-source-maps.md for the map contents.

---

lint

lessish lint [flags] FILE [FILE ...]

Runs the linter, prints diagnostics, and exits 1 if any warning/error remains. Full walkthrough: linter/01-overview.md.

$ lessish lint styles.less # exit: 1
styles.less:5:21: warning [hex-short] `#FFFFFF` can be shortened to `#fff`
styles.less:5:21: warning [hex-case] `#FFFFFF` should be lowercase
styles.less:6:11: warning [zero-unit] `0px` simplifies to `0`
styles.less:7:12: warning [block-opening-brace-newline-after] block content should start on a new line
styles.less:7:40: warning [closing-brace-newline-before] `}` should be on its own line
styles.less:3:1: info [decls-before-rulesets] declarations should come before nested rulesets

Flags

Flag	Effect
--fix	Apply safe autofixes (Tier 0 + Tier 1) in place.
--unsafe-fix	Also apply risky autofixes (Tier 2).
--full	Run eval-augmented rules (slower; runs the evaluator).
--format {text,json,github}	Output format. text is the default.
--config PATH	Load config from PATH instead of the default lookup.
--enable RULES	Comma-separated rule IDs to force-enable (repeatable).
--disable RULES	Comma-separated rule IDs to force-disable (repeatable).
--no-inline-config	Ignore all /* lessish-disable */ directives.
--cache DIR	Override cache location (default: auto-discovered).
--no-cache	Disable result caching (cache is on by default).
--project DIR	Cross-file mode.
--telemetry-out PATH	Write per-rule hit counts (JSON).

Rule catalog, tiers, cache, and --project details: linter/03-rules.md. Configuration and inline directives: linter/02-configuration.md.

Autofix

$ lessish lint --fix styles.less
$ lessish lint styles.less

(The first pass rewrites the file in place; the second finds nothing and exits 0.)

---

format

lessish format [--check] FILE [FILE ...]

A pure formatter — runs only Tier 0 rules, rewrites in place, no diagnostic output. Same engine as lessish lint --fix, but formatting-only and with blank-line-before-block on for the canonical layout.

$ lessish format messy.less
reformatted messy.less
$ cat messy.less
.a {
  color: red;
}

--check reports what would change and exits 1 if anything would, without writing:

$ lessish format --check messy.less # exit: 1
would reformat messy.less

---

Exit codes

Exit	Meaning
0	Success. For lint: no findings, or only info-level findings.
1	lint: a warning/error remained after --fix. format --check: a file would change.
2	Bad invocation, or an optional component isn't available.
3	I/O error (missing file, can't write output).

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