fix(test): improve cross-platform compatibility across unit tests

- Support CRLF line endings and skip hidden dot directories in nocopy invariant tests.
- Handle environment variable overrides and skip case-sensitive token priority tests on Windows.
- Use static OS and architecture values in Claude header fingerprint assertions for deterministic test results.

Closes: #5295

internal/api/handlers/management/config_basic_version_test.go

@@ -25,7 +25,9 @@ func TestSetLatestReleaseRequestHeaders(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			t.Setenv("GITHUB_TOKEN", tt.githubToken)
-			t.Setenv("github_token", "")
+			if tt.githubToken == "" {
+				t.Setenv("github_token", "")
+			}
 			t.Setenv("GITSTORE_GIT_TOKEN", "")
 			t.Setenv("GITSTORE_GIT_URL", "")
 

internal/managementasset/updater_test.go

@@ -10,7 +10,6 @@ import (
 
 func TestFetchLatestAssetSetsGitHubAuthorization(t *testing.T) {
 	t.Setenv("GITHUB_TOKEN", "asset-token")
-	t.Setenv("github_token", "")
 	t.Setenv("GITSTORE_GIT_TOKEN", "")
 	t.Setenv("GITSTORE_GIT_URL", "")
 

internal/runtime/executor/claude_executor_test.go

@@ -617,7 +617,7 @@ func TestApplyClaudeHeaders_DisableDeviceProfileStabilization(t *testing.T) {
 		"X-Stainless-Arch":            []string{"x64"},
 	})
 	applyClaudeHeaders(thirdPartyReq, auth, "key-disable-stability", false, nil, nil, cfg, nil, false)
-	assertClaudeFingerprint(t, thirdPartyReq.Header, "claude-cli/2.1.60 (external, cli)", "0.70.0", "v22.0.0", helps.MapStainlessOS(), helps.MapStainlessArch())
+	assertClaudeFingerprint(t, thirdPartyReq.Header, "claude-cli/2.1.60 (external, cli)", "0.70.0", "v22.0.0", "MacOS", "arm64")
 
 	lowerReq := newClaudeHeaderTestRequest(t, http.Header{
 		"User-Agent":                  []string{"claude-cli/2.1.61 (external, cli)"},
@@ -659,7 +659,7 @@ func TestApplyClaudeHeaders_LegacyModePreservesConfiguredUserAgentOverrideForCla
 	})
 	applyClaudeHeaders(req, auth, "key-legacy-ua-override", false, nil, nil, cfg, nil, true)
 
-	assertClaudeFingerprint(t, req.Header, "config-ua/1.0", "0.70.0", "v22.0.0", helps.MapStainlessOS(), helps.MapStainlessArch())
+	assertClaudeFingerprint(t, req.Header, "config-ua/1.0", "0.70.0", "v22.0.0", "MacOS", "arm64")
 }
 
 func TestApplyClaudeHeaders_LegacyThirdPartyUsesStableConfiguredOSArch(t *testing.T) {
@@ -816,7 +816,7 @@ func TestClaudeExecutor_NonClaudeRequestUsesClaudeCode220CLIFingerprint(t *testi
 		t.Fatalf("Execute() error = %v", errExecute)
 	}
 
-	assertClaudeFingerprint(t, seenHeaders, "claude-cli/2.1.220 (external, cli)", "0.94.0", "v26.3.0", helps.MapStainlessOS(), helps.MapStainlessArch())
+	assertClaudeFingerprint(t, seenHeaders, "claude-cli/2.1.220 (external, cli)", "0.94.0", "v26.3.0", "MacOS", "arm64")
 	if got := seenHeaders.Get("X-App"); got != "cli" {
 		t.Fatalf("X-App = %q, want cli", got)
 	}

internal/util/github_test.go

@@ -1,6 +1,9 @@
 package util
 
-import "testing"
+import (
+	"runtime"
+	"testing"
+)
 
 func TestResolveGitHubToken(t *testing.T) {
 	tests := []struct {
@@ -49,8 +52,19 @@ func TestResolveGitHubToken(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			t.Setenv("GITHUB_TOKEN", tt.githubToken)
-			t.Setenv("github_token", tt.lowerToken)
+			if runtime.GOOS == "windows" && tt.name == "GITHUB_TOKEN has highest priority" {
+				t.Skip("environment variables are case-insensitive on Windows")
+			}
+			if tt.githubToken != "" {
+				t.Setenv("GITHUB_TOKEN", tt.githubToken)
+			}
+			if tt.lowerToken != "" {
+				t.Setenv("github_token", tt.lowerToken)
+			}
+			if tt.githubToken == "" && tt.lowerToken == "" {
+				t.Setenv("GITHUB_TOKEN", "")
+				t.Setenv("github_token", "")
+			}
 			t.Setenv("GITSTORE_GIT_TOKEN", tt.gitStoreToken)
 			t.Setenv("GITSTORE_GIT_URL", tt.gitStoreURL)
 

internal/util/nocopy_invariant_test.go

@@ -26,8 +26,11 @@ func forEachSourceFile(t *testing.T, root string, visit func(rel string, data []
 			return err
 		}
 		if d.IsDir() {
+			if strings.HasPrefix(d.Name(), ".") {
+				return filepath.SkipDir
+			}
 			switch d.Name() {
-			case ".git", "vendor", "node_modules", "testdata":
+			case "vendor", "node_modules", "testdata":
 				return filepath.SkipDir
 			}
 			return nil
@@ -87,7 +90,7 @@ func TestNoInPlaceSJSONWrites(t *testing.T) {
 // new code rather than a proof of absence.
 var inPlaceByteWritePatterns = []*regexp.Regexp{
 	regexp.MustCompile(`\bcopy\([a-zA-Z_][A-Za-z0-9_.]*\[`),
-	regexp.MustCompile(`^\s*[a-zA-Z_][A-Za-z0-9_.]*\[[a-zA-Z0-9_]+\] = 0$`),
+	regexp.MustCompile(`^\s*[a-zA-Z_][A-Za-z0-9_.]*\[[a-zA-Z0-9_]+\] = 0\r?$`),
 }
 
 // reviewedInPlaceByteWrites records the reviewed in-place byte writes per file.
@@ -118,7 +121,8 @@ func TestInPlaceByteWritesAreReviewed(t *testing.T) {
 	root := repoRoot(t)
 	found := make(map[string][]string)
 	forEachSourceFile(t, root, func(rel string, data []byte) {
-		for _, line := range strings.Split(string(data), "\n") {
+		normalized := strings.ReplaceAll(string(data), "\r\n", "\n")
+		for _, line := range strings.Split(normalized, "\n") {
 			for _, pattern := range inPlaceByteWritePatterns {
 				if pattern.MatchString(line) {
 					found[rel] = append(found[rel], strings.TrimSpace(line))
@@ -162,3 +166,36 @@ func repoRoot(t *testing.T) string {
 		dir = parent
 	}
 }
+
+func TestInPlaceByteWritePatterns_CRLF(t *testing.T) {
+	crlfLine := "\traw[index] = 0\r"
+	matched := false
+	for _, pattern := range inPlaceByteWritePatterns {
+		if pattern.MatchString(crlfLine) {
+			matched = true
+			break
+		}
+	}
+	if !matched {
+		t.Fatalf("inPlaceByteWritePatterns failed to match CRLF line %q", crlfLine)
+	}
+}
+
+func TestForEachSourceFile_SkipsDotDirs(t *testing.T) {
+	tempDir := t.TempDir()
+	dotDir := filepath.Join(tempDir, ".gomodcache")
+	if err := os.MkdirAll(dotDir, 0755); err != nil {
+		t.Fatal(err)
+	}
+	sampleFile := filepath.Join(dotDir, "sample.go")
+	if err := os.WriteFile(sampleFile, []byte("package sample\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+	var visited []string
+	forEachSourceFile(t, tempDir, func(rel string, data []byte) {
+		visited = append(visited, rel)
+	})
+	if len(visited) > 0 {
+		t.Fatalf("forEachSourceFile should have skipped dot directories, but visited: %v", visited)
+	}
+}