test(config): cover defaults, YAML load, missing file, env overrides

internal/config/config_test.go

@@ -0,0 +1,80 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestDefault(t *testing.T) {
+	cfg := Default()
+	if cfg.Server.Address != ":4533" {
+		t.Errorf("default server address = %q, want :4533", cfg.Server.Address)
+	}
+	if cfg.Log.Level != "info" {
+		t.Errorf("default log level = %q, want info", cfg.Log.Level)
+	}
+}
+
+func TestLoadYAML(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.yaml")
+	content := []byte(`server:
+  address: ":9000"
+database:
+  url: "postgres://example"
+log:
+  level: "debug"
+  format: "json"
+`)
+	if err := os.WriteFile(path, content, 0o644); err != nil {
+		t.Fatal(err)
+	}
+	cfg, err := Load(path)
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.Server.Address != ":9000" {
+		t.Errorf("server.address = %q", cfg.Server.Address)
+	}
+	if cfg.Database.URL != "postgres://example" {
+		t.Errorf("database.url = %q", cfg.Database.URL)
+	}
+	if cfg.Log.Level != "debug" || cfg.Log.Format != "json" {
+		t.Errorf("log = %+v", cfg.Log)
+	}
+}
+
+func TestLoadMissingFileReturnsDefaults(t *testing.T) {
+	cfg, err := Load(filepath.Join(t.TempDir(), "does-not-exist.yaml"))
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.Server.Address != ":4533" {
+		t.Errorf("expected defaults, got %+v", cfg)
+	}
+}
+
+func TestEnvOverrides(t *testing.T) {
+	t.Setenv("SMARTMUSIC_SERVER_ADDRESS", ":8080")
+	t.Setenv("SMARTMUSIC_DATABASE_URL", "postgres://env")
+	t.Setenv("SMARTMUSIC_LOG_LEVEL", "WARN")
+	t.Setenv("SMARTMUSIC_LOG_FORMAT", "JSON")
+
+	cfg, err := Load("")
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.Server.Address != ":8080" {
+		t.Errorf("server.address = %q", cfg.Server.Address)
+	}
+	if cfg.Database.URL != "postgres://env" {
+		t.Errorf("database.url = %q", cfg.Database.URL)
+	}
+	if cfg.Log.Level != "warn" {
+		t.Errorf("log.level = %q, want lowercased warn", cfg.Log.Level)
+	}
+	if cfg.Log.Format != "json" {
+		t.Errorf("log.format = %q, want lowercased json", cfg.Log.Format)
+	}
+}