feat(gitlint): add gitlint linter

README.md

@@ -101,6 +101,7 @@ Other dedicated linters that are built-in are:
 | [Flake8][13]                       | `flake8`               |
 | [flawfinder][35]                   | `flawfinder`           |
 | [gdlint (gdtoolkit)][gdlint]       | `gdlint`               |
+| [gitlint][gitlint]                 | `gitlint`              |
 | [Golangci-lint][16]                | `golangcilint`         |
 | [glslc][glslc]                     | `glslc`                |
 | [DirectX Shader Compiler][dxc]     | `dxc`                  |
@@ -399,3 +400,4 @@ busted tests/
 [deno]: https://github.com/denoland/deno
 [standardjs]: https://standardjs.com/
 [biomejs]: https://github.com/biomejs/biome
+[gitlint]: https://github.com/jorisroovers/gitlint

lua/lint/linters/gitlint.lua

@@ -0,0 +1,9 @@
+return {
+  cmd = "gitlint",
+  stdin = false,
+  args = { "--staged", "--msg-filename" },
+  append_fname = true,
+  stream = "stderr",
+  ignore_exitcode = true,
+  parser = require("lint.parser").from_pattern([[^(\d+): (\w+) (.*)$]], { "lnum", "code", "message" }, nil, nil, nil),
+}

tests/gitlint_spec.lua

@@ -0,0 +1,17 @@
+describe("linter.gitlint", function()
+  it("can parse the output", function()
+    local parser = require("lint.linters.gitlint").parser
+    local result = parser([[3: B5 Body message is too short (11<20): "foo bar baz"]])
+    local expected = {
+      source = "gitlint",
+      message = "Body message is too short",
+      code = "B5",
+      lnum = 3,
+      col = 0,
+      end_lnum = 3,
+      end_col = 0,
+      severity = vim.diagnostic.severity.INFO,
+    }
+    assert.are.same(expected, result)
+  end)
+end)