fix(path): respect XDG_DATA_HOME on macOS and Windows

install.ps1

@@ -12,11 +12,14 @@ $ErrorActionPreference = "Stop"
 $REPO = "CodingWithCalvin/dtvem.cli"
 
 # Get dtvem root directory
-# Respects DTVEM_ROOT environment variable if set, otherwise uses default
+# Respects DTVEM_ROOT environment variable if set, XDG_DATA_HOME if set, otherwise uses default
 function Get-DtvemRoot {
     if ($env:DTVEM_ROOT) {
         return $env:DTVEM_ROOT
     }
+    if ($env:XDG_DATA_HOME) {
+        return "$env:XDG_DATA_HOME\dtvem"
+    }
     return "$env:USERPROFILE\.dtvem"
 }
 

install.sh

@@ -53,7 +53,7 @@ warning() {
 
 # Get dtvem root directory
 # On Linux, respects XDG_DATA_HOME if set (defaults to ~/.local/share/dtvem)
-# On macOS, uses ~/.dtvem
+# On macOS, uses XDG_DATA_HOME if explicitly set (opt-in), otherwise ~/.dtvem
 get_dtvem_root() {
     # Check for DTVEM_ROOT environment variable first (overrides all)
     if [ -n "$DTVEM_ROOT" ]; then
@@ -73,8 +73,12 @@ get_dtvem_root() {
             echo "$HOME/.local/share/dtvem"
         fi
     else
-        # macOS and others: use ~/.dtvem
-        echo "$HOME/.dtvem"
+        # macOS and others: use XDG_DATA_HOME if explicitly set (opt-in)
+        if [ -n "$XDG_DATA_HOME" ]; then
+            echo "$XDG_DATA_HOME/dtvem"
+        else
+            echo "$HOME/.dtvem"
+        fi
     fi
 }
 

src/internal/path/path.go

@@ -57,7 +57,12 @@ func ShimsDir() string {
 		return filepath.Join(home, ".local", "share", "dtvem", "shims")
 	}
 
-	// On macOS and Windows, use ~/.dtvem
+	// On macOS and Windows, use XDG_DATA_HOME if explicitly set (opt-in)
+	if xdgDataHome := os.Getenv("XDG_DATA_HOME"); xdgDataHome != "" {
+		return filepath.Join(xdgDataHome, "dtvem", "shims")
+	}
+
+	// Default for macOS and Windows: ~/.dtvem
 	return filepath.Join(home, ".dtvem", "shims")
 }
 

src/internal/path/path_test.go

@@ -109,6 +109,131 @@ func TestShimsDir(t *testing.T) {
 	}
 }
 
+func TestShimsDir_WithDTVEMROOT(t *testing.T) {
+	// Save original environment
+	originalRoot := os.Getenv("DTVEM_ROOT")
+	defer func() {
+		if originalRoot != "" {
+			_ = os.Setenv("DTVEM_ROOT", originalRoot)
+		} else {
+			_ = os.Unsetenv("DTVEM_ROOT")
+		}
+	}()
+
+	// Set custom DTVEM_ROOT
+	customRoot := filepath.Join(os.TempDir(), "custom-dtvem-root")
+	_ = os.Setenv("DTVEM_ROOT", customRoot)
+
+	result := ShimsDir()
+	expected := filepath.Join(customRoot, "shims")
+	if result != expected {
+		t.Errorf("ShimsDir() with DTVEM_ROOT=%q = %q, want %q", customRoot, result, expected)
+	}
+}
+
+func TestShimsDir_NonLinux_WithXDG(t *testing.T) {
+	// On non-Linux platforms, verify that XDG_DATA_HOME is respected when set
+	if runtime.GOOS == constants.OSLinux {
+		t.Skip("This test only runs on non-Linux platforms")
+	}
+
+	// Save original environment
+	originalRoot := os.Getenv("DTVEM_ROOT")
+	originalXDG := os.Getenv("XDG_DATA_HOME")
+	defer func() {
+		if originalRoot != "" {
+			_ = os.Setenv("DTVEM_ROOT", originalRoot)
+		} else {
+			_ = os.Unsetenv("DTVEM_ROOT")
+		}
+		if originalXDG != "" {
+			_ = os.Setenv("XDG_DATA_HOME", originalXDG)
+		} else {
+			_ = os.Unsetenv("XDG_DATA_HOME")
+		}
+	}()
+
+	// Clear DTVEM_ROOT and set XDG_DATA_HOME
+	_ = os.Unsetenv("DTVEM_ROOT")
+	customXDG := filepath.Join(os.TempDir(), "custom-xdg-data")
+	_ = os.Setenv("XDG_DATA_HOME", customXDG)
+
+	result := ShimsDir()
+	expected := filepath.Join(customXDG, "dtvem", "shims")
+
+	if result != expected {
+		t.Errorf("ShimsDir() on %s should use XDG_DATA_HOME when set, got %q, want %q",
+			runtime.GOOS, result, expected)
+	}
+}
+
+func TestShimsDir_NonLinux_WithoutXDG(t *testing.T) {
+	// On non-Linux platforms, verify that ~/.dtvem/shims is used when XDG_DATA_HOME is not set
+	if runtime.GOOS == constants.OSLinux {
+		t.Skip("This test only runs on non-Linux platforms")
+	}
+
+	// Save original environment
+	originalRoot := os.Getenv("DTVEM_ROOT")
+	originalXDG := os.Getenv("XDG_DATA_HOME")
+	defer func() {
+		if originalRoot != "" {
+			_ = os.Setenv("DTVEM_ROOT", originalRoot)
+		} else {
+			_ = os.Unsetenv("DTVEM_ROOT")
+		}
+		if originalXDG != "" {
+			_ = os.Setenv("XDG_DATA_HOME", originalXDG)
+		} else {
+			_ = os.Unsetenv("XDG_DATA_HOME")
+		}
+	}()
+
+	// Clear both DTVEM_ROOT and XDG_DATA_HOME
+	_ = os.Unsetenv("DTVEM_ROOT")
+	_ = os.Unsetenv("XDG_DATA_HOME")
+
+	result := ShimsDir()
+	home, _ := os.UserHomeDir()
+	expected := filepath.Join(home, ".dtvem", "shims")
+
+	if result != expected {
+		t.Errorf("ShimsDir() on %s without XDG_DATA_HOME should use ~/.dtvem/shims, got %q, want %q",
+			runtime.GOOS, result, expected)
+	}
+}
+
+func TestShimsDir_DTVEMRootOverridesXDG(t *testing.T) {
+	// Verify that DTVEM_ROOT takes precedence over XDG_DATA_HOME
+	originalRoot := os.Getenv("DTVEM_ROOT")
+	originalXDG := os.Getenv("XDG_DATA_HOME")
+	defer func() {
+		if originalRoot != "" {
+			_ = os.Setenv("DTVEM_ROOT", originalRoot)
+		} else {
+			_ = os.Unsetenv("DTVEM_ROOT")
+		}
+		if originalXDG != "" {
+			_ = os.Setenv("XDG_DATA_HOME", originalXDG)
+		} else {
+			_ = os.Unsetenv("XDG_DATA_HOME")
+		}
+	}()
+
+	// Set both DTVEM_ROOT and XDG_DATA_HOME
+	customRoot := filepath.Join(os.TempDir(), "custom-dtvem-root")
+	_ = os.Setenv("DTVEM_ROOT", customRoot)
+	_ = os.Setenv("XDG_DATA_HOME", filepath.Join(os.TempDir(), "should-be-ignored"))
+
+	result := ShimsDir()
+	expected := filepath.Join(customRoot, "shims")
+
+	if result != expected {
+		t.Errorf("ShimsDir() with DTVEM_ROOT set should return DTVEM_ROOT/shims, got %q, want %q",
+			result, expected)
+	}
+}
+
 func TestLookPathExcludingShims(t *testing.T) {
 	originalPath := os.Getenv("PATH")
 	defer func() { _ = os.Setenv("PATH", originalPath) }()