Fix index-out-of-range panic in wrapError at EOF (#272)

`wrapError` walks `p.lexer.input[i]` for `i < int(p.Pos())` to compute the
error line/column. At EOF `p.Pos()` can exceed `len(input)`, so on input like
`CREATE--` (a trailing comment leaves the position past the end) it panics
with "index out of range".

Clamp the loop bound to `len(p.lexer.input)`.

Add `CREATE--` to TestParser_InvalidSyntax to reproduce: it panicked before
the fix and now returns a proper error.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: 3 people

parser/parser_common.go

@@ -384,7 +384,13 @@ func (p *Parser) wrapError(err error) error {
 	lineNo := 0
 	column := 0
 
-	for i := 0; i < int(p.Pos()); i++ {
+	// p.Pos() can exceed the input length when the lexer is at EOF,
+	// so clamp the upper bound to avoid an index-out-of-range panic.
+	upperBound := int(p.Pos())
+	if upperBound > len(p.lexer.input) {
+		upperBound = len(p.lexer.input)
+	}
+	for i := 0; i < upperBound; i++ {
 		if p.lexer.input[i] == '\n' {
 			lineNo++
 			column = 0

parser/parser_test.go

@@ -186,7 +186,8 @@ func TestParser_InvalidSyntax(t *testing.T) {
 		// Invalid ARRAY JOIN types (only ARRAY JOIN, LEFT ARRAY JOIN, and INNER ARRAY JOIN are valid)
 		"SELECT * FROM t RIGHT ARRAY JOIN arr AS a", // RIGHT ARRAY JOIN not supported
 		"SELECT * FROM t FULL ARRAY JOIN arr AS a",  // FULL ARRAY JOIN not supported
-		"00e1d", // invalid number that leaves lastToken nil
+		"00e1d",    // invalid number that leaves lastToken nil
+		"CREATE--", // trailing comment pushes p.Pos() past end of input (wrapError out-of-range)
 		// Inputs that previously caused a nil-pointer dereference while
 		// formatting the error message at EOF (p.last() is nil).
 		"ALTER ",