chore(go): wrap core filesystem errors with context

internal/homesick/core/helpers_test.go

@@ -17,6 +17,12 @@ func (errReader) Read(_ []byte) (int, error) {
 	return 0, errors.New("boom")
 }
 
+type errWriter struct{}
+
+func (errWriter) Write(_ []byte) (int, error) {
+	return 0, errors.New("boom")
+}
+
 func TestRunGitPretendWritesStatus(t *testing.T) {
 	stdout := &bytes.Buffer{}
 	app := &App{Stdout: stdout, Stderr: bytes.NewBuffer(nil), Pretend: true}
@@ -119,6 +125,19 @@ func TestLinkPath(t *testing.T) {
 		require.NoError(t, statErr)
 		require.True(t, info.Mode()&os.ModeSymlink != 0)
 	})
+
+	t.Run("create destination parent error includes context", func(t *testing.T) {
+		dir := t.TempDir()
+		source := filepath.Join(dir, "source")
+		blocker := filepath.Join(dir, "blocker")
+		require.NoError(t, os.WriteFile(source, []byte("x"), 0o644))
+		require.NoError(t, os.WriteFile(blocker, []byte("x"), 0o644))
+
+		app := &App{Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+		err := app.linkPath(source, filepath.Join(blocker, "dest"))
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "create destination parent")
+	})
 }
 
 func TestReadSubdirsAndMatchesIgnoredDir(t *testing.T) {
@@ -141,6 +160,12 @@ func TestReadSubdirsAndMatchesIgnoredDir(t *testing.T) {
 	require.False(t, notIgnored)
 }
 
+func TestReadSubdirsReadErrorIncludesContext(t *testing.T) {
+	_, err := readSubdirs(t.TempDir())
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "read subdirs")
+}
+
 func TestPullAndPushDefaultCastlePretend(t *testing.T) {
 	dir := t.TempDir()
 	stdout := &bytes.Buffer{}
@@ -230,6 +255,15 @@ func TestConfirmDestroyReadError(t *testing.T) {
 	ok, err := app.confirmDestroy("dotfiles")
 	require.Error(t, err)
 	require.False(t, ok)
+	require.Contains(t, err.Error(), "read destroy confirmation")
+}
+
+func TestConfirmDestroyWriteError(t *testing.T) {
+	app := &App{Stdout: errWriter{}, Stdin: strings.NewReader("yes\n")}
+	ok, err := app.confirmDestroy("dotfiles")
+	require.Error(t, err)
+	require.False(t, ok)
+	require.Contains(t, err.Error(), "write destroy prompt")
 }
 
 func TestExecAllWrapsCastleError(t *testing.T) {