Add --port

internal/config/config_test.go

@@ -165,3 +165,43 @@ func TestDefaultExpiryMustFitWithinMax(t *testing.T) {
 		t.Error("an unlimited default under a finite maximum was accepted")
 	}
 }
+
+func TestPortOverridesListen(t *testing.T) {
+	cases := []struct {
+		listen string
+		port   int
+		want   string
+	}{
+		{"127.0.0.1:8080", 0, "127.0.0.1:8080"},
+		{"127.0.0.1:8080", 9000, "127.0.0.1:9000"},
+		{"0.0.0.0:8080", 3000, "0.0.0.0:3000"},
+		{"localhost", 3000, "localhost:3000"}, // a bare host is fine with --port
+		{"[::1]:8080", 3000, "[::1]:3000"},
+	}
+	for _, c := range cases {
+		cfg := &Config{
+			Listen: c.listen, Port: c.port, BasePath: "/", DataDir: "d",
+			SweepInterval: time.Minute, MaxConcurrent: 1,
+		}
+		if err := cfg.Normalise(); err != nil {
+			t.Errorf("listen %q port %d: %v", c.listen, c.port, err)
+			continue
+		}
+		if cfg.Listen != c.want {
+			t.Errorf("listen %q port %d => %q, want %q", c.listen, c.port, cfg.Listen, c.want)
+		}
+	}
+
+	for _, c := range []struct {
+		listen string
+		port   int
+	}{{"127.0.0.1:8080", 70000}, {"127.0.0.1:8080", -1}, {"localhost", 0}} {
+		cfg := &Config{
+			Listen: c.listen, Port: c.port, BasePath: "/", DataDir: "d",
+			SweepInterval: time.Minute, MaxConcurrent: 1,
+		}
+		if err := cfg.Normalise(); err == nil {
+			t.Errorf("listen %q port %d was accepted", c.listen, c.port)
+		}
+	}
+}