loc

loc scans the current directory tree and reports lines of code by language, separating test code from non-test code and emitting pretty JSON via prettyx.

Install

go build -o bin/loc -trimpath -ldflags="-s -w" .
sudo install bin/loc /usr/local/bin/

# or...
go install pkt.systems/loc@latest

Usage

loc [flags] [extensions...]

By default, loc scans the current working directory and counts all supported languages. Providing extensions limits the scan to those languages. Use -d multiple times to scan and aggregate multiple directories. Repository-local .gitignore files are honored while scanning.

Examples:

loc
loc .go
loc .go .c .cpp
loc -d proj1 -d proj2

Extension filters

When you pass extensions, loc expands them to the full set of extensions for the matching languages. This avoids partial counts for languages that use multiple extensions.

Examples:

• loc .h counts C and Objective-C headers and also includes their related extensions (e.g. .c, .m, .mm).
• loc .m includes MATLAB and Objective-C sources (disambiguated by content).

Ambiguous extensions like .h and .m are resolved by inspecting file content.

Output

The JSON includes:

• loc, test_loc, code_loc
• percent_test_loc, percent_code_loc (100 == 100%)
• languages map with per-language loc, test_loc, code_loc
• Optional test counters (e.g., Go test_count, example_count, benchmark_count, fuzz_count)

Supported languages

• Go (.go)
• Kotlin (.kt, .kts)
• Java (.java)
• JavaScript (.js, .jsx, .mjs, .cjs)
• TypeScript (.ts, .tsx, .mts, .cts)
• Python (.py)
• PHP (.php)
• Ruby (.rb)
• Rust (.rs)
• Swift (.swift)
• C (.c, .h)
• C++ (.cpp, .cc, .cxx, .hpp, .hh, .hxx)
• Objective-C (.m, .mm, .h)
• C# (.cs)
• Scala (.scala)
• Groovy (.groovy)
• Perl (.pl, .pm, .t)
• Dart (.dart)
• Lua (.lua)
• R (.r, .R)
• MATLAB (.m)
• Shell (.sh, .bash, .zsh)

Test detection (high-level)

Tests are detected using common, deterministic conventions:

• Go: _test.go files; counts Test, Example, Benchmark, Fuzz functions.
• Java/Kotlin: src/test or *Test.*; counts @Test.
• JS/TS: __tests__, test/, tests/, *.test.*, *.spec.*; counts describe/it/test.
• Python: test_*.py/*_test.py or tests/; counts def test_.
• PHP: tests/ or *Test.php; counts @test and function test*.
• Ruby: test/ or spec/; counts def test_, describe, it.
• Rust: tests/ or *_test.rs for test LOC; counts #[test] anywhere.
• Swift: Tests/ or *Tests.swift; counts func test*.
• C/C++/Shell: test LOC via test(s)/ or filename patterns; no test counts.
• Objective-C: Tests/ or *Test(s).m/.mm; counts - (void)test*.
• C#: test LOC via test(s)/ or *Test(s).cs; counts [Test], [Fact], [Theory].
• Scala: src/test or *Test.scala; counts test(/it(/should(.
• Groovy: src/test or *Test.groovy; counts @Test or def "...".
• Perl: t/ or *.t; counts ok( and subtest(.
• Dart: test/ or *_test.dart; counts test( and group(.
• Lua: spec/ or *_spec.lua; counts describe/it.
• R: tests/ or testthat/; counts test_that(.
• MATLAB: tests/ or *_test.m; no test counts.