fix(postgres,pgx): error instead of panicking on unquoted MigrationsTable

When MigrationsTableQuoted is enabled and MigrationsTable contains no
double quotes (including when it is left empty and defaults to
schema_migrations), the quote matcher returns no matches and
result[len(result)-1] panics with an out-of-range index. Return a
configuration error instead, matching the existing too many dot
characters path.

Add regression tests for the postgres, pgx and pgx/v5 drivers.

Author: xianyu-sheng

database/pgx/pgx.go

@@ -129,6 +129,9 @@ func WithInstance(instance *sql.DB, config *Config) (database.Driver, error) {
 	if config.MigrationsTableQuoted {
 		re := regexp.MustCompile(`"(.*?)"`)
 		result := re.FindAllStringSubmatch(config.MigrationsTable, -1)
+		if len(result) == 0 {
+			return nil, fmt.Errorf("\"%s\" MigrationsTable is not quoted", config.MigrationsTable)
+		}
 		config.migrationsTableName = result[len(result)-1][1]
 		if len(result) == 2 {
 			config.migrationsSchemaName = result[0][1]

database/pgx/pgx_quoted_test.go

@@ -0,0 +1,54 @@
+package pgx
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+	"testing"
+)
+
+// pingOnlyDriver lets tests build a *sql.DB that answers Ping without a real
+// database, which is all WithInstance needs when DatabaseName and SchemaName
+// are set in the config.
+type pingOnlyDriver struct{}
+
+func (pingOnlyDriver) Open(string) (driver.Conn, error) { return pingOnlyConn{}, nil }
+
+type pingOnlyConn struct{}
+
+func (pingOnlyConn) Prepare(string) (driver.Stmt, error) {
+	return nil, errors.New("prepare not supported")
+}
+
+func (pingOnlyConn) Close() error { return nil }
+
+func (pingOnlyConn) Begin() (driver.Tx, error) {
+	return nil, errors.New("transactions not supported")
+}
+
+func (pingOnlyConn) Ping(context.Context) error { return nil }
+
+var _ driver.Pinger = pingOnlyConn{}
+
+func init() { sql.Register("migrate-fake-pgx", pingOnlyDriver{}) }
+
+// TestWithInstanceQuotedTableWithoutQuotes ensures a quoted-table config whose
+// table name contains no quotes returns an error instead of panicking.
+func TestWithInstanceQuotedTableWithoutQuotes(t *testing.T) {
+	db, err := sql.Open("migrate-fake-pgx", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() { _ = db.Close() }()
+
+	_, err = WithInstance(db, &Config{
+		DatabaseName:          "testdb",
+		SchemaName:            "public",
+		MigrationsTable:       "schema_migrations",
+		MigrationsTableQuoted: true,
+	})
+	if err == nil {
+		t.Fatal("expected an error when MigrationsTableQuoted is set without a quoted table name")
+	}
+}

database/pgx/v5/pgx.go

@@ -109,6 +109,9 @@ func WithInstance(instance *sql.DB, config *Config) (database.Driver, error) {
 	if config.MigrationsTableQuoted {
 		re := regexp.MustCompile(`"(.*?)"`)
 		result := re.FindAllStringSubmatch(config.MigrationsTable, -1)
+		if len(result) == 0 {
+			return nil, fmt.Errorf("\"%s\" MigrationsTable is not quoted", config.MigrationsTable)
+		}
 		config.migrationsTableName = result[len(result)-1][1]
 		if len(result) == 2 {
 			config.migrationsSchemaName = result[0][1]

database/pgx/v5/pgx_quoted_test.go

@@ -0,0 +1,54 @@
+package pgx
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+	"testing"
+)
+
+// pingOnlyDriver lets tests build a *sql.DB that answers Ping without a real
+// database, which is all WithInstance needs when DatabaseName and SchemaName
+// are set in the config.
+type pingOnlyDriver struct{}
+
+func (pingOnlyDriver) Open(string) (driver.Conn, error) { return pingOnlyConn{}, nil }
+
+type pingOnlyConn struct{}
+
+func (pingOnlyConn) Prepare(string) (driver.Stmt, error) {
+	return nil, errors.New("prepare not supported")
+}
+
+func (pingOnlyConn) Close() error { return nil }
+
+func (pingOnlyConn) Begin() (driver.Tx, error) {
+	return nil, errors.New("transactions not supported")
+}
+
+func (pingOnlyConn) Ping(context.Context) error { return nil }
+
+var _ driver.Pinger = pingOnlyConn{}
+
+func init() { sql.Register("migrate-fake-pgx5", pingOnlyDriver{}) }
+
+// TestWithInstanceQuotedTableWithoutQuotes ensures a quoted-table config whose
+// table name contains no quotes returns an error instead of panicking.
+func TestWithInstanceQuotedTableWithoutQuotes(t *testing.T) {
+	db, err := sql.Open("migrate-fake-pgx5", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() { _ = db.Close() }()
+
+	_, err = WithInstance(db, &Config{
+		DatabaseName:          "testdb",
+		SchemaName:            "public",
+		MigrationsTable:       "schema_migrations",
+		MigrationsTableQuoted: true,
+	})
+	if err == nil {
+		t.Fatal("expected an error when MigrationsTableQuoted is set without a quoted table name")
+	}
+}

database/postgres/postgres.go

@@ -109,6 +109,9 @@ func WithConnection(ctx context.Context, conn *sql.Conn, config *Config) (*Postg
 	if config.MigrationsTableQuoted {
 		re := regexp.MustCompile(`"(.*?)"`)
 		result := re.FindAllStringSubmatch(config.MigrationsTable, -1)
+		if len(result) == 0 {
+			return nil, fmt.Errorf("\"%s\" MigrationsTable is not quoted", config.MigrationsTable)
+		}
 		config.migrationsTableName = result[len(result)-1][1]
 		if len(result) == 2 {
 			config.migrationsSchemaName = result[0][1]

database/postgres/postgres_quoted_test.go

@@ -0,0 +1,54 @@
+package postgres
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+	"testing"
+)
+
+// pingOnlyDriver lets tests build a *sql.DB that answers Ping without a real
+// database, which is all WithInstance needs when DatabaseName and SchemaName
+// are set in the config.
+type pingOnlyDriver struct{}
+
+func (pingOnlyDriver) Open(string) (driver.Conn, error) { return pingOnlyConn{}, nil }
+
+type pingOnlyConn struct{}
+
+func (pingOnlyConn) Prepare(string) (driver.Stmt, error) {
+	return nil, errors.New("prepare not supported")
+}
+
+func (pingOnlyConn) Close() error { return nil }
+
+func (pingOnlyConn) Begin() (driver.Tx, error) {
+	return nil, errors.New("transactions not supported")
+}
+
+func (pingOnlyConn) Ping(context.Context) error { return nil }
+
+var _ driver.Pinger = pingOnlyConn{}
+
+func init() { sql.Register("migrate-fake-postgres", pingOnlyDriver{}) }
+
+// TestWithInstanceQuotedTableWithoutQuotes ensures a quoted-table config whose
+// table name contains no quotes returns an error instead of panicking.
+func TestWithInstanceQuotedTableWithoutQuotes(t *testing.T) {
+	db, err := sql.Open("migrate-fake-postgres", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() { _ = db.Close() }()
+
+	_, err = WithInstance(db, &Config{
+		DatabaseName:          "testdb",
+		SchemaName:            "public",
+		MigrationsTable:       "schema_migrations",
+		MigrationsTableQuoted: true,
+	})
+	if err == nil {
+		t.Fatal("expected an error when MigrationsTableQuoted is set without a quoted table name")
+	}
+}