1 files changed, 111 insertions, 0 deletions
diff --git a/pgruntime/target_test.go b/pgruntime/target_test.go
new file mode 100644
index 0000000..d62721c
--- /dev/null
+++ b/pgruntime/target_test.go
@@ -0,0 +1,111 @@
+// SPDX-FileCopyrightText: 2026 Stefan Majewsky <majewsky@gmx.net>
+// SPDX-License-Identifier: Apache-2.0
+
+package pgruntime_test
+
+import (
+	"net/url"
+	"strings"
+	"testing"
+
+	"go.xyrillian.de/gg/assert"
+	"go.xyrillian.de/gg/pgruntime"
+)
+
+func TestParseConnectionTargetSuccess(t *testing.T) {
+	testCases := map[string]pgruntime.ConnectionTarget{
+		// minimal case: just the required fields are set
+		`postgresql://alice@localhost/bookstore`: {
+			HostName:     "localhost",
+			UserName:     "alice",
+			DatabaseName: "bookstore",
+		},
+		// maximal case: all required fields are set
+		`postgres://alice:swordfish@db.example.com:5432/bookstore?sslmode=prefer&application_name=frontdesk`: {
+			HostName:          "db.example.com",
+			Port:              "5432",
+			UserName:          "alice",
+			Password:          "swordfish",
+			DatabaseName:      "bookstore",
+			ConnectionOptions: "sslmode=prefer&application_name=frontdesk",
+		},
+	}
+
+	for input, expected := range testCases {
+		t.Run(input, func(t *testing.T) {
+			u, err := url.Parse(input)
+			if !assert.ErrEqual(t, err, nil) {
+				t.FailNow()
+			}
+			parsed, err := pgruntime.ParseConnectionTargetFromURL(u)
+			if !assert.ErrEqual(t, err, nil) {
+				t.FailNow()
+			}
+			assert.Equal(t, parsed, expected)
+			serialized, err := parsed.IntoURL()
+			if !assert.ErrEqual(t, err, nil) {
+				t.FailNow()
+			}
+			// IntoURL() always uses postgres://, so this is not always an exact roundtrip
+			assert.Equal(t, serialized.String(), strings.ReplaceAll(input, "postgresql:", "postgres:"))
+		})
+	}
+}
+
+func TestParseConnectionTargetFailure(t *testing.T) {
+	testCases := map[string]string{
+		`https://alice@db.example.com/foo?sslmode=prefer`:            `expected scheme "postgres" or "postgresql", but got "https"`,
+		`postgres:foo?sslmode=prefer`:                                `expected authority component, but got rootless path "foo"`,
+		`postgres://alice@db.example.com/foo#sslmode=prefer`:         `unexpected fragment "sslmode=prefer"`,
+		`postgres://alice@db.example.com::5432/foo?sslmode=prefer`:   `malformed host "db.example.com::5432"`,
+		`postgres://alice@db.example.com/foo/bar?sslmode=prefer`:     `malformed database name "foo/bar"`,
+		`postgres://alice@db.example.com/foo?sslmode=prefer;foo=bar`: `malformed connection options: invalid semicolon separator in query`,
+	}
+	for input, expected := range testCases {
+		t.Run(input, func(t *testing.T) {
+			u, err := url.Parse(input)
+			if !assert.ErrEqual(t, err, nil) {
+				t.FailNow()
+			}
+			_, err = pgruntime.ParseConnectionTargetFromURL(u)
+			assert.ErrEqual(t, err, "in ParseConnectionTargetFromURL: "+expected)
+		})
+	}
+}
+
+func TestSerializeConnectionOptions(t *testing.T) {
+	ct := pgruntime.ConnectionTarget{
+		HostName:     "localhost",
+		UserName:     "alice",
+		DatabaseName: "bookstore",
+	}
+
+	// cannot merge ConnectionOptions if the string part is malformed
+	ct.ConnectionOptions = `sslmode=prefer;foo=bar`
+	ct.ExtraConnectionOptions = url.Values{"application_name": {"frontdesk"}}
+	_, err := ct.IntoURL()
+	assert.ErrEqual(t, err, `in ConnectionTarget.IntoURL: malformed connection options: invalid semicolon separator in query`)
+
+	// successful trivial merges
+	ct.ConnectionOptions = `sslmode=prefer`
+	ct.ExtraConnectionOptions = nil
+	u, err := ct.IntoURL()
+	if assert.ErrEqual(t, err, nil) {
+		assert.Equal(t, u.RawQuery, `sslmode=prefer`)
+	}
+
+	ct.ConnectionOptions = ""
+	ct.ExtraConnectionOptions = url.Values{"application_name": {"frontdesk"}}
+	u, err = ct.IntoURL()
+	if assert.ErrEqual(t, err, nil) {
+		assert.Equal(t, u.RawQuery, `application_name=frontdesk`)
+	}
+
+	// successful complex merge
+	ct.ConnectionOptions = `sslmode=prefer`
+	ct.ExtraConnectionOptions = url.Values{"application_name": {"frontdesk"}}
+	u, err = ct.IntoURL()
+	if assert.ErrEqual(t, err, nil) {
+		assert.Equal(t, u.RawQuery, `application_name=frontdesk&sslmode=prefer`)
+	}
+}