[+] make sure pgxmockPool.Config() initializes ConnConfig (#223)

driver.go

@@ -45,7 +45,7 @@ func (p *pgxmockPool) Acquire(context.Context) (*pgxpool.Conn, error) {
 }
 
 func (p *pgxmockPool) Config() *pgxpool.Config {
-	return &pgxpool.Config{}
+	return &pgxpool.Config{ConnConfig: &pgx.ConnConfig{}}
 }
 
 // AsConn is similar to Acquire but returns proper mocking interface

driver_test.go

@@ -62,3 +62,28 @@ func TestPoolStat(t *testing.T) {
 		t.Error("expected stat object, but got nil")
 	}
 }
+
+func TestPoolConfig(t *testing.T) {
+	mock, err := NewPool()
+	if err != nil {
+		t.Fatalf("expected no error, but got: %s", err)
+	}
+	c := mock.Config()
+	if c == nil {
+		t.Fatal("expected config object, but got nil")
+	}
+	if c.ConnConfig == nil {
+		t.Fatal("expected conn config object, but got nil")
+	}
+}
+
+func TestConnConfig(t *testing.T) {
+	mock, err := NewConn()
+	if err != nil {
+		t.Fatalf("expected no error, but got: %s", err)
+	}
+	c := mock.Config()
+	if c == nil {
+		t.Fatal("expected config object, but got nil")
+	}
+}