fix: use token.SEMICOLON constant instead of string comparison

The parser was comparing token.Type (which is token.Type alias for string)
with string literals "SEMICOLON" and checking non-existent Literal field.
Fixed to use proper token.SEMICOLON constant for both Parse() and ParseContext().

This resolves the validation errors on SQL files with trailing semicolons.

Author: Ajit Pratap Singh

pkg/sql/parser/parser.go

@@ -60,9 +60,9 @@ func (p *Parser) Parse(tokens []token.Token) (*ast.AST, error) {
 	result.Statements = make([]ast.Statement, 0, estimatedStmts)
 
 	// Parse statements
-	for p.currentPos < len(tokens) && p.currentToken.Type != "EOF" {
+	for p.currentPos < len(tokens) && p.currentToken.Type != token.EOF {
 		// Skip semicolons between statements
-		if p.currentToken.Type == "SEMICOLON" || p.currentToken.Literal == ";" {
+		if p.currentToken.Type == token.SEMICOLON {
 			p.advance()
 			continue
 		}
@@ -76,7 +76,7 @@ func (p *Parser) Parse(tokens []token.Token) (*ast.AST, error) {
 		result.Statements = append(result.Statements, stmt)
 
 		// Optionally consume semicolon after statement
-		if p.currentToken.Type == "SEMICOLON" || p.currentToken.Literal == ";" {
+		if p.currentToken.Type == token.SEMICOLON {
 			p.advance()
 		}
 	}
@@ -134,7 +134,7 @@ func (p *Parser) ParseContext(ctx context.Context, tokens []token.Token) (*ast.A
 	result.Statements = make([]ast.Statement, 0, estimatedStmts)
 
 	// Parse statements
-	for p.currentPos < len(tokens) && p.currentToken.Type != "EOF" {
+	for p.currentPos < len(tokens) && p.currentToken.Type != token.EOF {
 		// Check context before each statement
 		if err := ctx.Err(); err != nil {
 			// Clean up the AST on error
@@ -143,7 +143,7 @@ func (p *Parser) ParseContext(ctx context.Context, tokens []token.Token) (*ast.A
 		}
 
 		// Skip semicolons between statements
-		if p.currentToken.Type == "SEMICOLON" || p.currentToken.Literal == ";" {
+		if p.currentToken.Type == token.SEMICOLON {
 			p.advance()
 			continue
 		}
@@ -157,7 +157,7 @@ func (p *Parser) ParseContext(ctx context.Context, tokens []token.Token) (*ast.A
 		result.Statements = append(result.Statements, stmt)
 
 		// Optionally consume semicolon after statement
-		if p.currentToken.Type == "SEMICOLON" || p.currentToken.Literal == ";" {
+		if p.currentToken.Type == token.SEMICOLON {
 			p.advance()
 		}
 	}