ci(GitHub): auto-commit changes from jobs

* Added composite .github/actions/auto-commit
* Using stefanzweifel/git-auto-commit-action@v6.0.1
* Extended w/ comment step explaining the auto-commit.

* Added auto-commit to linting/lint job.
* Further configured golangci-lint to enable all linters.
* & addressed all linting problems.

Closes #8

Signed-off-by: Stefan Zimmermann <user@zimmermann.co>

Author: userzimmermann

.github/actions/auto-commit/action.yml

@@ -0,0 +1,42 @@
+name: Auto-commit changes
+description: Composite action for auto-committing changes made by jobs
+outputs:
+  changes-detected:
+    description: Whether changes were detected & committed
+    value: ${{ steps.auto_commit.outputs.changes_detected }}
+
+  commit-hash:
+    description: SHA hash of the auto-commit
+    value: ${{ steps.auto_commit.outputs.commit_hash }}
+
+runs:
+  using: composite
+  steps:
+    - name: Auto-commit changes made by job
+      id: auto_commit
+      if: github.event_name == 'pull_request'
+      uses: stefanzweifel/git-auto-commit-action@778341af668090896ca464160c2def5d1d1a3eb0 # v6.0.1
+      with:
+        commit_message: Auto-fix from ${{ github.workflow }} / ${{ github.job }} job
+        status_options: --untracked-files=no
+
+    - name: Comment on PR about the auto-commit
+      if: github.event_name == 'pull_request' && steps.auto_commit.outputs.changes_detected == 'true'
+      uses: actions/github-script@v8
+      with:
+        script: |
+            const repositoryUrl = '${{ github.server_url }}/${{ github.repository }}'
+
+            await github.rest.issues.createComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                body: `
+            **Auto-fix applied from ${{ github.workflow }}** / \`${{ github.job }}\` job
+
+            * Workflow run: ${repositoryUrl}/actions/runs/${{ github.run_id }}
+            * Fix commit: ${repositoryUrl}/commit/${{ steps.auto_commit.outputs.commit_hash }}
+
+            @${{ github.event.pull_request.user.login }}: `
+            + 'Please check the auto-changes, pull them, squash commits, & force-push to continue the PR review ...'
+            })

.github/workflows/linting.yml

@@ -1,30 +1,52 @@
-name: Lint & format
+name: Linting
 on:
   push:
   pull_request:
 
+permissions:
+  contents: write
+  pull-requests: write
+
 jobs:
   lint:
+    name: Lint w/ golangci-lint ${{ github.event_name == 'pull_request' && '(auto-fix)' || '' }}
     runs-on: ubuntu-latest
-    permissions:
-      contents: write
-
     steps:
     - uses: actions/checkout@v5
       with:
         fetch-depth: 0
+        submodules: recursive
+
+        # Avoid merge commits when auto-committing fixes ...
+        ref: ${{ github.head_ref || github.ref }}
 
     - name: Setup Go environment
       uses: actions/setup-go@v6
       with:
         go-version: 1.25.1
 
     - name: Run go mod tidy
-      run: go mod tidy
+      run: |
+          go mod tidy
 
     - name: Install & run golangci-lint
+      if: github.event_name == 'push'
       uses: golangci/golangci-lint-action@4afd733a84b1f43292c63897423277bb7f4313a9 # v8
       with:
+        install-mode: goinstall
         version: latest
-        install-mode: "goinstall"
-        args: --fix
+        args: --default all # ${{ github.event_name == 'pull_request' && '--fix' || '' }}
+
+    - name: Install & run golangci-lint w/ reviewdog
+      if: github.event_name == 'pull_request'
+      uses: reviewdog/action-golangci-lint@f9bba13753278f6a73b27a56a3ffb1bfda90ed71 # v2.8.0
+      with:
+        cache: false
+        reporter: github-pr-review
+        golangci_lint_flags: --default all --fix
+        level: error
+        fail_level: any
+
+    - name: Auto-commit lint fixes
+      if: github.event_name == 'pull_request' && (success() || failure())  # (golangci-lint succeeds when all is auto-fixed)
+      uses: ./.github/actions/auto-commit

.golangci.yml

@@ -0,0 +1,14 @@
+version: '2'
+linters: 
+  disable:
+    - wsl # <-- Auto-switches to wsl_v5.
+
+  settings: 
+    depguard: 
+      rules: 
+        main:
+          list-mode: strict
+          allow:
+            - $gostd
+            - github.com/samber/lo
+            - github.com/stretchr/testify

pointer.go

@@ -44,3 +44,7 @@ func NotNilPtr[T any](name string, value *T) *T {
 	lo.Assertf(value != nil, "%s should not be a nil pointer", name)
 	return value
 }
+
+// bla
+func _() {
+}

pointer_test.go

@@ -7,7 +7,9 @@ import (
 )
 
 func TestNilPtr(t *testing.T) {
+	t.Parallel()
 	t.Run("should accept nil pointer & return nil", func(t *testing.T) {
+		t.Parallel()
 		var nilPtr *int
 		assert.Nil(t, NilPtr("Test pointer", nilPtr))
 	})
@@ -45,10 +47,9 @@ func TestNotNilPtr(t *testing.T) {
 }
 
 func BenchmarkNilPtr(b *testing.B) {
-	var nilPtr *int
 	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		NilPtr("Benchmark pointer", nilPtr)
+	for range b.N {
+		NilPtr("Benchmark pointer", (*int)(nil))
 	}
 }