fix(cli): quote identifiers in generated migrations

cmd/limen/driver.go

@@ -14,6 +14,10 @@ type Driver interface {
 	IntrospectColumnsQuery(tableName string) (string, []any)
 	IntrospectIndexesQuery(tableName string) (string, []any)
 	IntrospectForeignKeysQuery(tableName string) (string, []any)
+	// QuoteIdentifier quotes a table, column, index or constraint name for this
+	// database, so that reserved words and case-sensitive names survive into
+	// the generated DDL. Must agree with how the runtime adapter quotes.
+	QuoteIdentifier(name string) string
 	MapGoTypeToSQL(goType limen.ColumnType, isAutoIncrement bool) string
 	MapSQLTypeToGoType(dataType string) limen.ColumnType
 	GetAutoIncrementSuffix() string

cmd/limen/driver_base.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"fmt"
 	"strings"
 
 	"github.com/thecodearcher/limen"
@@ -42,10 +41,6 @@ func (d *baseDriver) ParseForeignKeyRow(scan func(dest ...any) error) (limen.For
 	}, nil
 }
 
-func (d *baseDriver) DropColumnSQL(tableName, columnName string) string {
-	return fmt.Sprintf("DROP COLUMN %s", columnName)
-}
-
 func (d *baseDriver) ParseColumnRow(scan func(dest ...any) error) (limen.ColumnDefinition, error) {
 	var colName string
 

cmd/limen/driver_mysql.go

@@ -19,6 +19,24 @@ func NewMySQLDriver() Driver {
 	return &mysqlDriver{}
 }
 
+// mysqlQuoteChar is MySQL's and MariaDB's identifier quote. It is accepted in
+// every sql_mode, including ANSI_QUOTES, where " also becomes an identifier
+// quote.
+const mysqlQuoteChar = "`"
+
+// QuoteIdentifier quotes a table, column, index or constraint name, doubling
+// any embedded backtick so the result stays a single identifier. It mirrors
+// adapters/sql's quoteIdent, since the generator and the runtime adapter must
+// agree on the name a table actually has.
+//
+// Hand-rolled because go-sql-driver/mysql exports no equivalent of pgx's
+// Identifier.Sanitize.
+func (d *mysqlDriver) QuoteIdentifier(name string) string {
+	return mysqlQuoteChar +
+		strings.ReplaceAll(name, mysqlQuoteChar, mysqlQuoteChar+mysqlQuoteChar) +
+		mysqlQuoteChar
+}
+
 func (d *mysqlDriver) Name() string {
 	return string(DriverMySQL)
 }
@@ -133,9 +151,13 @@ func (d *mysqlDriver) FormatDefaultValue(defaultValue string) string {
 }
 
 func (d *mysqlDriver) DropIndexSQL(tableName, indexName string) string {
-	return fmt.Sprintf("DROP INDEX %s ON %s", indexName, tableName)
+	return fmt.Sprintf("DROP INDEX %s ON %s", d.QuoteIdentifier(indexName), d.QuoteIdentifier(tableName))
 }
 
 func (d *mysqlDriver) DropForeignKeySQL(tableName, constraintName string) string {
-	return fmt.Sprintf("DROP FOREIGN KEY %s", constraintName)
+	return fmt.Sprintf("DROP FOREIGN KEY %s", d.QuoteIdentifier(constraintName))
+}
+
+func (d *mysqlDriver) DropColumnSQL(tableName, columnName string) string {
+	return fmt.Sprintf("DROP COLUMN %s", d.QuoteIdentifier(columnName))
 }

cmd/limen/driver_postgres.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/jackc/pgx/v5"
 	_ "github.com/jackc/pgx/v5/stdlib"
 
 	"github.com/thecodearcher/limen"
@@ -19,6 +20,13 @@ func NewPostgresDriver() Driver {
 	return &postgresDriver{}
 }
 
+// QuoteIdentifier defers to pgx, which is already this driver's connection
+// library, rather than re-deriving PostgreSQL's quoting rules. Beyond doubling
+// embedded quotes it also strips NUL bytes, which PostgreSQL rejects outright.
+func (d *postgresDriver) QuoteIdentifier(name string) string {
+	return pgx.Identifier{name}.Sanitize()
+}
+
 func (d *postgresDriver) Name() string {
 	return string(DriverPostgres)
 }
@@ -182,9 +190,13 @@ func (d *postgresDriver) FormatDefaultValue(defaultValue string) string {
 }
 
 func (d *postgresDriver) DropIndexSQL(tableName, indexName string) string {
-	return fmt.Sprintf("DROP INDEX IF EXISTS %s", indexName)
+	return fmt.Sprintf("DROP INDEX IF EXISTS %s", d.QuoteIdentifier(indexName))
 }
 
 func (d *postgresDriver) DropForeignKeySQL(tableName, constraintName string) string {
-	return fmt.Sprintf("DROP CONSTRAINT %s", constraintName)
+	return fmt.Sprintf("DROP CONSTRAINT %s", d.QuoteIdentifier(constraintName))
+}
+
+func (d *postgresDriver) DropColumnSQL(tableName, columnName string) string {
+	return fmt.Sprintf("DROP COLUMN %s", d.QuoteIdentifier(columnName))
 }

cmd/limen/migration_generator.go

@@ -38,13 +38,28 @@ func (s *sqlMigrationGenerator) generateDownMigration(schema *limen.SchemaDefini
 	if diff != nil && diff.HasChanges() {
 		return s.generateAlterDownMigration(schema.GetTableName(), diff)
 	}
-	return fmt.Sprintf("DROP TABLE IF EXISTS %s;", schema.GetTableName()), nil
+	return fmt.Sprintf("DROP TABLE IF EXISTS %s;", s.quote(string(schema.GetTableName()))), nil
+}
+
+// quote quotes a single identifier for the target database.
+func (s *sqlMigrationGenerator) quote(name string) string {
+	return s.driver.QuoteIdentifier(name)
+}
+
+// quoteAll quotes each identifier and joins them with separator, for the
+// column lists in PRIMARY KEY and CREATE INDEX.
+func quoteAll[T ~string](s *sqlMigrationGenerator, names []T, separator string) string {
+	quoted := make([]string, len(names))
+	for i := range names {
+		quoted[i] = s.quote(string(names[i]))
+	}
+	return strings.Join(quoted, separator)
 }
 
 func (s *sqlMigrationGenerator) generateCreateTable(schema *limen.SchemaDefinition) (string, error) {
 	var buf strings.Builder
 
-	fmt.Fprintf(&buf, "CREATE TABLE IF NOT EXISTS %s (\n", schema.GetTableName())
+	fmt.Fprintf(&buf, "CREATE TABLE IF NOT EXISTS %s (\n", s.quote(string(schema.GetTableName())))
 
 	columns := make([]string, 0, len(schema.Columns))
 	for _, field := range schema.Columns {
@@ -61,7 +76,7 @@ func (s *sqlMigrationGenerator) generateCreateTable(schema *limen.SchemaDefiniti
 	}
 
 	if len(pkFields) > 0 {
-		fmt.Fprintf(&buf, ",\n  PRIMARY KEY (%s)", strings.Join(pkFields, ", "))
+		fmt.Fprintf(&buf, ",\n  PRIMARY KEY (%s)", quoteAll(s, pkFields, ", "))
 	}
 
 	for _, fk := range schema.ForeignKeys {
@@ -107,7 +122,11 @@ func (s *sqlMigrationGenerator) generateAlterDownMigration(tableName limen.Schem
 	statements := []string{}
 
 	for _, idx := range diff.AddedIndexes {
-		dropSQL := s.driver.DropIndexSQL(string(tableName), idx.Name)
+		// DropIndexSQL is a standalone statement but carries no terminator,
+		// unlike DropColumnSQL and DropForeignKeySQL, which are fragments of
+		// the ALTER TABLE appended below. Without the semicolon the two run
+		// together into one statement the database rejects.
+		dropSQL := s.driver.DropIndexSQL(string(tableName), idx.Name) + ";"
 		statements = append(statements, dropSQL)
 	}
 
@@ -135,7 +154,7 @@ func (s *sqlMigrationGenerator) generateUpAlterTableStatement(tableName limen.Sc
 	var buf strings.Builder
 	statements := []string{}
 
-	fmt.Fprintf(&buf, "ALTER TABLE %s\n", tableName)
+	fmt.Fprintf(&buf, "ALTER TABLE %s\n", s.quote(string(tableName)))
 	for _, col := range diff.AddedColumns {
 		colDef := s.generateColumnDefinition(&col)
 		statements = append(statements, fmt.Sprintf("ADD COLUMN %s", colDef))
@@ -161,7 +180,7 @@ func (s *sqlMigrationGenerator) generateDownAlterTableStatement(tableName limen.
 	var buf strings.Builder
 	statements := []string{}
 
-	fmt.Fprintf(&buf, "ALTER TABLE %s\n", tableName)
+	fmt.Fprintf(&buf, "ALTER TABLE %s\n", s.quote(string(tableName)))
 
 	for _, fk := range diff.AddedForeignKeys {
 		dropOp := s.driver.DropForeignKeySQL(string(tableName), fk.Name)
@@ -181,7 +200,7 @@ func (s *sqlMigrationGenerator) generateDownAlterTableStatement(tableName limen.
 }
 
 func (s *sqlMigrationGenerator) generateColumnDefinition(field *limen.ColumnDefinition) string {
-	parts := []string{field.Name}
+	parts := []string{s.quote(field.Name)}
 
 	isAutoIncrement := field.LogicalField == limen.SchemaIDField && s.useAutoIncrementIDs
 
@@ -214,10 +233,12 @@ func (s *sqlMigrationGenerator) generateForeignKeyStatement(fk *limen.ForeignKey
 
 	if alterTable {
 		fmt.Fprintf(&buf, "ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)",
-			fk.Name, fk.Column, string(fk.ReferencedSchema), string(fk.ReferencedField))
+			s.quote(fk.Name), s.quote(string(fk.Column)),
+			s.quote(string(fk.ReferencedSchema)), s.quote(string(fk.ReferencedField)))
 	} else {
 		fmt.Fprintf(&buf, ",\nCONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)",
-			fk.Name, fk.Column, string(fk.ReferencedSchema), string(fk.ReferencedField))
+			s.quote(fk.Name), s.quote(string(fk.Column)),
+			s.quote(string(fk.ReferencedSchema)), s.quote(string(fk.ReferencedField)))
 	}
 
 	if fk.OnDelete != "" {
@@ -234,20 +255,9 @@ func (s *sqlMigrationGenerator) generateForeignKeyStatement(fk *limen.ForeignKey
 func (s *sqlMigrationGenerator) generateCreateIndexStatement(idx *limen.IndexDefinition, tableName limen.SchemaTableName) string {
 	if idx.Unique {
 		return fmt.Sprintf("CREATE UNIQUE INDEX %s ON %s (%s);",
-			idx.Name, tableName, joinCustomStringSlice(idx.Columns, ", "))
+			s.quote(idx.Name), s.quote(string(tableName)), quoteAll(s, idx.Columns, ", "))
 	}
 
 	return fmt.Sprintf("CREATE INDEX %s ON %s (%s);",
-		idx.Name, tableName, joinCustomStringSlice(idx.Columns, ", "))
-}
-
-func joinCustomStringSlice[T ~string](fields []T, separator string) string {
-	var joined string
-	for i := range fields {
-		joined += string(fields[i])
-		if i < len(fields)-1 {
-			joined += separator
-		}
-	}
-	return joined
+		s.quote(idx.Name), s.quote(string(tableName)), quoteAll(s, idx.Columns, ", "))
 }