Normalize vscode-extension PURLs

ecosystem.go

@@ -5,19 +5,20 @@ import (
 )
 
 const (
-	ecosystemAlpine        = "alpine"
-	ecosystemArch          = "arch"
-	ecosystemComposer      = "composer"
-	ecosystemGit           = "git"
-	ecosystemGitHubActions = "github-actions"
-	ecosystemGolang        = "golang"
-	ecosystemMaven         = "maven"
-	ecosystemNPM           = "npm"
-	ecosystemPackagist     = "packagist"
-	ecosystemRubyGems      = "rubygems"
-	ecosystemSwift         = "swift"
-	purlTypeGem            = "gem"
-	purlTypeGitHubActions  = "githubactions"
+	ecosystemAlpine         = "alpine"
+	ecosystemArch           = "arch"
+	ecosystemComposer       = "composer"
+	ecosystemGit            = "git"
+	ecosystemGitHubActions  = "github-actions"
+	ecosystemGolang         = "golang"
+	ecosystemMaven          = "maven"
+	ecosystemNPM            = "npm"
+	ecosystemPackagist      = "packagist"
+	ecosystemRubyGems       = "rubygems"
+	ecosystemSwift          = "swift"
+	purlTypeGem             = "gem"
+	purlTypeGitHubActions   = "githubactions"
+	purlTypeVSCodeExtension = "vscode-extension"
 )
 
 // purlTypeForEcosystem maps ecosystem names to PURL types.

makepurl.go

@@ -93,6 +93,7 @@ func normalizeComponents(purlType, namespace, name, version, registryURL string)
 		Qualifiers: q,
 	}
 	_ = p.Normalize()
+	lowercaseCaseInsensitive(&p)
 	return p.Namespace, p.Name, p.Version
 }
 
@@ -234,6 +235,8 @@ func splitNamespace(ecosystem, name string) (namespace, pkgName string, ok bool)
 				pkgName = rest
 			}
 		}
+	case purlTypeVSCodeExtension:
+		return splitVSCodeExtension(name)
 	case ecosystemSwift:
 		i := strings.LastIndexByte(name, '/')
 		if i <= 0 || i == len(name)-1 {
@@ -249,6 +252,15 @@ func splitNamespace(ecosystem, name string) (namespace, pkgName string, ok bool)
 	return
 }
 
+// splitVSCodeExtension splits VS Code's publisher.name extension identifier.
+func splitVSCodeExtension(name string) (publisher, extension string, ok bool) {
+	publisher, extension, ok = strings.Cut(name, ".")
+	if !ok || publisher == "" || extension == "" {
+		return "", "", false
+	}
+	return publisher, extension, true
+}
+
 // writeComponentEscaped writes s to b, percent-encoding characters that are not safe
 // in PURL path components (namespace, name, version).
 func writeComponentEscaped(b *strings.Builder, s string) {

purl.go

@@ -33,9 +33,19 @@ func Parse(s string) (*PURL, error) {
 			p.Name = path + "/" + p.Name
 		}
 	}
+	lowercaseCaseInsensitive(&p)
 	return &PURL{p}, nil
 }
 
+// lowercaseCaseInsensitive lowercases components the spec declares
+// case-insensitive where packageurl-go's Normalize leaves them as given.
+func lowercaseCaseInsensitive(p *packageurl.PackageURL) {
+	if p.Type == purlTypeVSCodeExtension {
+		p.Namespace = strings.ToLower(p.Namespace)
+		p.Name = strings.ToLower(p.Name)
+	}
+}
+
 // New creates a new PURL from components.
 //
 // The result is normalized with the same per-type rules Parse applies
@@ -57,6 +67,7 @@ func New(purlType, namespace, name, version string, qualifiers map[string]string
 	}
 	p := packageurl.NewPackageURL(purlType, namespace, name, version, q, "")
 	_ = p.Normalize()
+	lowercaseCaseInsensitive(p)
 	return &PURL{*p}
 }
 

vscode_test.go

@@ -0,0 +1,55 @@
+package purl_test
+
+import (
+	"testing"
+
+	"github.com/git-pkgs/purl"
+)
+
+func TestVSCodeExtensionCase(t *testing.T) {
+	const want = "pkg:vscode-extension/ms-python/python@2023.25.10292213"
+	parsed, err := purl.Parse("pkg:vscode-extension/MS-Python/Python@2023.25.10292213")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, got := range []string{
+		parsed.String(),
+		purl.New("vscode-extension", "MS-Python", "Python", "2023.25.10292213", nil).String(),
+		purl.MakePURL("vscode-extension", "MS-Python.Python", "2023.25.10292213").String(),
+		purl.MakePURLString("vscode-extension", "MS-Python.Python", "2023.25.10292213"),
+		purl.BuildPURLString("vscode-extension", "MS-Python.Python", "2023.25.10292213", ""),
+	} {
+		if got != want {
+			t.Errorf("got %q, want %q", got, want)
+		}
+	}
+}
+
+func TestVSCodeExtensionOpenVSX(t *testing.T) {
+	const want = "pkg:vscode-extension/muhammad-sammy/csharp@2.15.30-RC1?platform=linux-x64&repository_url=https:%2F%2Fopen-vsx.org"
+	parsed, err := purl.Parse("pkg:vscode-extension/Muhammad-Sammy/CSharp@2.15.30-RC1?platform=linux-x64&repository_url=https:%2F%2Fopen-vsx.org")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := parsed.String(); got != want {
+		t.Errorf("Parse() = %q, want %q", got, want)
+	}
+	if !parsed.IsPrivateRegistry() {
+		t.Error("open-vsx.org should not be the default registry")
+	}
+	built := purl.BuildPURLString("vscode-extension", "Muhammad-Sammy.CSharp", "2.15.30", "https://open-vsx.org")
+	if built != "pkg:vscode-extension/muhammad-sammy/csharp@2.15.30?repository_url=https:%2F%2Fopen-vsx.org" {
+		t.Errorf("BuildPURLString() = %q", built)
+	}
+}
+
+func TestVSCodeExtensionRequiresPublisher(t *testing.T) {
+	for _, name := range []string{"python", ".python", "ms-python.", "ms-python/python"} {
+		if got := purl.MakePURLString("vscode-extension", name, "1.0.0"); got != "" {
+			t.Errorf("MakePURLString(%q) = %q, want empty", name, got)
+		}
+		if got := purl.MakePURL("vscode-extension", name, "1.0.0"); got != nil {
+			t.Errorf("MakePURL(%q) = %q, want nil", name, got)
+		}
+	}
+}