task 003: handle home-dir and APKG marshal errors

2 files changed, 47 insertions, 0 deletions

diff --git a/internal/config/home.go b/internal/config/home.go
new file mode 100644
index 0000000..8089b6e
--- /dev/null
+++ b/internal/config/home.go
@@ -0,0 +1,22 @@
+package config
+
+import (
+	"fmt"
+	"os"
+)
+
+var userHomeDir = os.UserHomeDir
+
+// HomeDir returns the user's home directory.
+//
+// It falls back to "." when the home directory cannot be resolved so callers
+// can still build a safe relative path instead of joining against an empty
+// string.
+func HomeDir() (string, error) {
+	homeDir, err := userHomeDir()
+	if err != nil {
+		return ".", fmt.Errorf("resolve home directory: %w", err)
+	}
+
+	return homeDir, nil
+}
diff --git a/internal/config/home_test.go b/internal/config/home_test.go
new file mode 100644
index 0000000..bc7f5ea
--- /dev/null
+++ b/internal/config/home_test.go
@@ -0,0 +1,25 @@
+package config
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestHomeDirReturnsFallbackWhenResolutionFails(t *testing.T) {
+	oldUserHomeDir := userHomeDir
+	t.Cleanup(func() {
+		userHomeDir = oldUserHomeDir
+	})
+
+	userHomeDir = func() (string, error) {
+		return "", errors.New("boom")
+	}
+
+	homeDir, err := HomeDir()
+	if err == nil {
+		t.Fatal("HomeDir() error = nil, want error")
+	}
+	if homeDir != "." {
+		t.Fatalf("HomeDir() homeDir = %q, want %q", homeDir, ".")
+	}
+}