Revert handling of mixed case action identifiers (21836f4)

As motivated by the changes to the specification.

Author: ericcornelissen

CHANGELOG.md

@@ -12,6 +12,12 @@ Versioning].
 
 ## [Unreleased]
 
+### Bug
+
+- Revert handling of mixed case action identifiers.
+
+## [v0.6.2] - 2026-01-04
+
 ### Enhancements
 
 - Handle mixed case action identifiers.

SPECIFICATION.md

@@ -118,11 +118,9 @@ only the workflow at the path declared in the `uses:` value. If multiple
 reusable workflow from the same repository are used, each workflow must be
 handled.
 
-The resulting is a collection of Action identifiers, `<owner>/<project>@<ref>`,
-of which the `<owner>` and `<project>` are normalized to all lowercase (because
-GitHub Actions is case insensitive in these). That is, if a project uses
-`actions/checkout@v1.2.3` and `Actions/Checkout@v1.2.3` the collection will only
-contain `actions/checkout@v1.2.3`.
+The resulting is a collection of Action identifiers, `<owner>/<project>@<ref>`.
+While GitHub Actions is case-insensitive when resolving `<owner>/<project>`,
+these must NOT be normalized (as that would break on case sensitive OSes).
 
 Docker Hub Actions, as seen in the example below, are excluded from the set of
 actions the repository depends on (see [#216]).

internal/gha/parse.go

@@ -89,7 +89,7 @@ func parseUses(uses string) (GitHubAction, error) {
 		return a, ErrInvalidUsesRepo
 	}
 
-	a.Owner = strings.ToLower(repo[:i])
+	a.Owner = repo[:i]
 	project := repo[i+1:]
 
 	// split "project" into "project"[/"path"]
@@ -101,6 +101,6 @@ func parseUses(uses string) (GitHubAction, error) {
 		project = project[:i]
 	}
 
-	a.Project = strings.ToLower(project)
+	a.Project = project
 	return a, nil
 }

internal/gha/parse_test.go

@@ -95,7 +95,7 @@ func TestParseUses(t *testing.T) {
 			"uppercase in owner": {
 				uses: "Foo/bar/baz@v42",
 				want: GitHubAction{
-					Owner:   "foo",
+					Owner:   "Foo",
 					Project: "bar",
 					Path:    "baz",
 					Ref:     "v42",
@@ -105,7 +105,7 @@ func TestParseUses(t *testing.T) {
 				uses: "foo/Bar/baz@v42",
 				want: GitHubAction{
 					Owner:   "foo",
-					Project: "bar",
+					Project: "Bar",
 					Path:    "baz",
 					Ref:     "v42",
 				},
@@ -273,8 +273,8 @@ func TestParseUses(t *testing.T) {
 				return false
 			}
 
-			return action.Owner == strings.ToLower(owner) &&
-				action.Project == strings.ToLower(project) &&
+			return action.Owner == owner &&
+				action.Project == project &&
 				action.Path == path &&
 				action.Ref == ref
 		}

testdata/init/success.txtar

@@ -50,16 +50,6 @@ jobs:
       run: Echo 'hello world!'
   example-2:
     uses: actions/reusable/.github/workflows/workflow.yml@v2
-  example-3:
-    name: example case insensitivity
-    runs-on: ubuntu-22.04
-    steps:
-    - name: Checkout repository
-      uses: Actions/checkout@main
-    - name: Install Go
-      uses: actions/Setup-Go@v5.0.0
-      with:
-        go-version-file: go.mod
 -- .cache/actions/checkout/main/action.yml --
 name: actions/checkout@main
 -- .cache/actions/composite/v1/action.yml --

testdata/list/success.txtar

@@ -63,16 +63,6 @@ jobs:
       run: Echo 'hello world!'
   example-2:
     uses: actions/reusable/.github/workflows/workflow.yml@v2
-  example-3:
-    name: example case insensitivity
-    runs-on: ubuntu-22.04
-    steps:
-    - name: Checkout repository
-      uses: Actions/checkout@main
-    - name: Install Go
-      uses: actions/Setup-Go@v5.0.0
-      with:
-        go-version-file: go.mod
 -- .cache/actions/checkout/main/action.yml --
 name: actions/checkout@main
 -- .cache/actions/composite/v1/action.yml --

testdata/update/success.txtar

@@ -103,16 +103,6 @@ jobs:
       run: Echo 'hello world!'
   example-2:
     uses: actions/reusable/.github/workflows/workflow.yml@v2
-  example-3:
-    name: example case insensitivity
-    runs-on: ubuntu-22.04
-    steps:
-    - name: Checkout repository
-      uses: Actions/checkout@v4.1.1
-    - name: Install Go
-      uses: actions/Setup-Go@v5.0.0
-      with:
-        go-version-file: go.mod
 -- changed/.github/actions/hello-world-action/action.yml --
 name: Hello world action
 description: Says 'Hello world!'

testdata/verify/success.txtar

@@ -87,16 +87,6 @@ jobs:
       run: Echo 'hello world!'
   example-2:
     uses: actions/reusable/.github/workflows/workflow.yml@v2
-  example-3:
-    name: example case insensitivity
-    runs-on: ubuntu-22.04
-    steps:
-    - name: Checkout repository
-      uses: Actions/checkout@main
-    - name: Install Go
-      uses: actions/Setup-Go@v5.0.0
-      with:
-        go-version-file: go.mod
 -- redundant/.github/actions/hello-world-action/action.yml --
 name: Hello world action
 description: Says 'Hello world!'