Fix Docker Desktop detection via ~/.docker/run/docker.sock (#206)

Author: carole-lavillonniere

internal/runtime/docker.go

@@ -57,20 +57,24 @@ func NewDockerRuntime(dockerHost string) (*DockerRuntime, error) {
 	return &DockerRuntime{client: cli}, nil
 }
 
+func vmSocketPaths(home string) []string {
+	return []string{
+		filepath.Join(home, ".docker", "run", "docker.sock"),
+		filepath.Join(home, ".colima", "default", "docker.sock"),
+		filepath.Join(home, ".colima", "docker.sock"),
+		filepath.Join(home, ".orbstack", "run", "docker.sock"),
+		filepath.Join(home, ".lima", "docker", "sock", "docker.sock"),
+	}
+}
+
 func findDockerSocket() string {
-	// Lima VM: Docker socket is natively available at the standard path.
-	// Lima sets LIMA_INSTANCE inside the VM.
+	// Lima sets LIMA_INSTANCE inside the VM; the socket is at the standard path natively.
 	if os.Getenv("LIMA_INSTANCE") != "" {
 		return "/var/run/docker.sock"
 	}
 
 	home, _ := os.UserHomeDir()
-	return probeSocket(
-		filepath.Join(home, ".colima", "default", "docker.sock"),
-		filepath.Join(home, ".colima", "docker.sock"),
-		filepath.Join(home, ".orbstack", "run", "docker.sock"),
-		filepath.Join(home, ".lima", "docker", "sock", "docker.sock"),
-	)
+	return probeSocket(vmSocketPaths(home)...)
 }
 
 func probeSocket(candidates ...string) string {
@@ -82,21 +86,15 @@ func probeSocket(candidates ...string) string {
 	return ""
 }
 
-// isVM reports whether the Docker daemon is running inside a VM (e.g., Colima, OrbStack).
+// isVM reports whether the Docker daemon is running inside a VM (e.g., Docker Desktop, Colima, OrbStack, Lima).
 // In these cases the socket is remapped inside the VM and the container sees it at
 // /var/run/docker.sock even if the CLI connects via a user-scoped socket path.
 func (d *DockerRuntime) isVM() bool {
 	host := d.client.DaemonHost()
 	if strings.HasPrefix(host, "unix://") {
 		socketPath := strings.TrimPrefix(host, "unix://")
-		// Check for known VM-based Docker socket locations
 		home, _ := os.UserHomeDir()
-		vmSockets := []string{
-			filepath.Join(home, ".colima", "default", "docker.sock"),
-			filepath.Join(home, ".colima", "docker.sock"),
-			filepath.Join(home, ".orbstack", "run", "docker.sock"),
-		}
-		for _, vmSock := range vmSockets {
+		for _, vmSock := range vmSocketPaths(home) {
 			if socketPath == vmSock {
 				return true
 			}

internal/runtime/docker_test.go

@@ -87,45 +87,35 @@ func TestSocketPath_VMDetection(t *testing.T) {
 	t.Cleanup(func() { _ = os.RemoveAll(home) })
 	t.Setenv("HOME", home)
 
-	t.Run("colima socket exists returns remapped path", func(t *testing.T) {
-		colimaSock := filepath.Join(home, ".colima", "default", "docker.sock")
-		require.NoError(t, os.MkdirAll(filepath.Dir(colimaSock), 0o755))
-		f, err := os.Create(colimaSock)
-		require.NoError(t, err)
-		require.NoError(t, f.Close())
-		t.Cleanup(func() {
-			require.NoError(t, os.Remove(colimaSock))
-		})
-
-		cli, err := client.NewClientWithOpts(client.WithHost("unix://" + colimaSock))
-		require.NoError(t, err)
-		rt := &DockerRuntime{client: cli}
-		assert.Equal(t, "/var/run/docker.sock", rt.SocketPath())
-	})
+	vmTests := []struct {
+		name    string
+		relPath string
+	}{
+		{"docker desktop", ".docker/run/docker.sock"},
+		{"colima", ".colima/default/docker.sock"},
+		{"orbstack", ".orbstack/run/docker.sock"},
+		{"lima host", ".lima/docker/sock/docker.sock"},
+	}
 
-	t.Run("orbstack socket exists returns remapped path", func(t *testing.T) {
-		orbstackSock := filepath.Join(home, ".orbstack", "run", "docker.sock")
-		require.NoError(t, os.MkdirAll(filepath.Dir(orbstackSock), 0o755))
-		f, err := os.Create(orbstackSock)
-		require.NoError(t, err)
-		require.NoError(t, f.Close())
-		t.Cleanup(func() {
-			require.NoError(t, os.Remove(orbstackSock))
+	for _, tc := range vmTests {
+		t.Run(tc.name+" socket returns remapped path", func(t *testing.T) {
+			sock := filepath.Join(home, filepath.FromSlash(tc.relPath))
+			require.NoError(t, os.MkdirAll(filepath.Dir(sock), 0o755))
+			require.NoError(t, os.WriteFile(sock, nil, 0o600))
+			t.Cleanup(func() { require.NoError(t, os.Remove(sock)) })
+
+			cli, err := client.NewClientWithOpts(client.WithHost("unix://" + sock))
+			require.NoError(t, err)
+			rt := &DockerRuntime{client: cli}
+			assert.Equal(t, "/var/run/docker.sock", rt.SocketPath())
 		})
+	}
 
-		cli, err := client.NewClientWithOpts(client.WithHost("unix://" + orbstackSock))
-		require.NoError(t, err)
-		rt := &DockerRuntime{client: cli}
-		assert.Equal(t, "/var/run/docker.sock", rt.SocketPath())
-	})
-
-	t.Run("rootless socket exists returns actual path", func(t *testing.T) {
+	t.Run("rootless socket returns actual path", func(t *testing.T) {
 		// Use a non-VM socket path (short path to avoid Docker client limit)
 		rootlessSock := "/tmp/lstk-docker.sock"
 		require.NoError(t, os.WriteFile(rootlessSock, nil, 0o600))
-		t.Cleanup(func() {
-			require.NoError(t, os.Remove(rootlessSock))
-		})
+		t.Cleanup(func() { require.NoError(t, os.Remove(rootlessSock)) })
 
 		cli, err := client.NewClientWithOpts(client.WithHost("unix://" + rootlessSock))
 		require.NoError(t, err)
@@ -161,16 +151,28 @@ func TestFindDockerSocket_LimaVM(t *testing.T) {
 	assert.Equal(t, "/var/run/docker.sock", sock)
 }
 
-func TestFindDockerSocket_IncludesLimaPathOnHost(t *testing.T) {
+func TestFindDockerSocket_ProbesVMSockets(t *testing.T) {
 	t.Setenv("LIMA_INSTANCE", "")
 
-	tmpDir := t.TempDir()
-	limaSock := filepath.Join(tmpDir, ".lima", "docker", "sock", "docker.sock")
-	require.NoError(t, os.MkdirAll(filepath.Dir(limaSock), 0o700))
-	require.NoError(t, os.WriteFile(limaSock, nil, 0o600))
+	tests := []struct {
+		name    string
+		relPath string
+	}{
+		{"docker desktop", ".docker/run/docker.sock"},
+		{"colima", ".colima/default/docker.sock"},
+		{"orbstack", ".orbstack/run/docker.sock"},
+		{"lima host", ".lima/docker/sock/docker.sock"},
+	}
 
-	t.Setenv("HOME", tmpDir)
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			tmpDir := t.TempDir()
+			sock := filepath.Join(tmpDir, filepath.FromSlash(tc.relPath))
+			require.NoError(t, os.MkdirAll(filepath.Dir(sock), 0o700))
+			require.NoError(t, os.WriteFile(sock, nil, 0o600))
+			t.Setenv("HOME", tmpDir)
 
-	result := findDockerSocket()
-	assert.Equal(t, limaSock, result)
+			assert.Equal(t, sock, findDockerSocket())
+		})
+	}
 }