Ignore comments when deciding when to replace quetion marks.

dialects/filter.go

@@ -23,13 +23,45 @@ type SeqFilter struct {
 func convertQuestionMark(sql, prefix string, start int) string {
 	var buf strings.Builder
 	var beginSingleQuote bool
+	var isLineComment bool
+	var isComment bool
+	var isMaybeLineComment bool
+	var isMaybeComment bool
+	var isMaybeCommentEnd bool
 	var index = start
 	for _, c := range sql {
-		if !beginSingleQuote && c == '?' {
+		if !beginSingleQuote && !isLineComment && !isComment && c == '?' {
 			buf.WriteString(fmt.Sprintf("%s%v", prefix, index))
 			index++
 		} else {
-			if c == '\'' {
+			if isMaybeLineComment {
+				if c == '-' {
+					isLineComment = true
+				}
+				isMaybeLineComment = false
+			} else if isMaybeComment {
+				if c == '*' {
+					isComment = true
+				}
+				isMaybeComment = false
+			} else if isMaybeCommentEnd {
+				if c == '/' {
+					isComment = false
+				}
+				isMaybeCommentEnd = false
+			} else if isLineComment {
+				if c == '\n' {
+					isLineComment = false
+				}
+			} else if isComment {
+				if c == '*' {
+					isMaybeCommentEnd = true
+				}
+			} else if !beginSingleQuote && c == '-' {
+				isMaybeLineComment = true
+			} else if !beginSingleQuote && c == '/' {
+				isMaybeComment = true
+			} else if c == '\'' {
 				beginSingleQuote = !beginSingleQuote
 			}
 			buf.WriteRune(c)

dialects/filter_test.go

@@ -19,3 +19,60 @@ func TestSeqFilter(t *testing.T) {
 		assert.EqualValues(t, result, convertQuestionMark(sql, "$", 1))
 	}
 }
+
+func TestSeqFilterLineComment(t *testing.T) {
+	var kases = map[string]string{
+		`SELECT *
+		FROM TABLE1
+		WHERE foo='bar'
+		AND a=? -- it's a comment
+		AND b=?`: `SELECT *
+		FROM TABLE1
+		WHERE foo='bar'
+		AND a=$1 -- it's a comment
+		AND b=$2`,
+		`SELECT *
+		FROM TABLE1
+		WHERE foo='bar'
+		AND a=? -- it's a comment?
+		AND b=?`: `SELECT *
+		FROM TABLE1
+		WHERE foo='bar'
+		AND a=$1 -- it's a comment?
+		AND b=$2`,
+		`SELECT *
+		FROM TABLE1
+		WHERE a=? -- it's a comment? and that's okay?
+		AND b=?`: `SELECT *
+		FROM TABLE1
+		WHERE a=$1 -- it's a comment? and that's okay?
+		AND b=$2`,
+	}
+	for sql, result := range kases {
+		assert.EqualValues(t, result, convertQuestionMark(sql, "$", 1))
+	}
+}
+
+func TestSeqFilterComment(t *testing.T) {
+	var kases = map[string]string{
+		`SELECT *
+		FROM TABLE1
+		WHERE a=? /* it's a comment */
+		AND b=?`: `SELECT *
+		FROM TABLE1
+		WHERE a=$1 /* it's a comment */
+		AND b=$2`,
+		`SELECT /* it's a comment * ?
+		More comment on the next line! */ *
+		FROM TABLE1
+		WHERE a=? /**/
+		AND b=?`: `SELECT /* it's a comment * ?
+		More comment on the next line! */ *
+		FROM TABLE1
+		WHERE a=$1 /**/
+		AND b=$2`,
+	}
+	for sql, result := range kases {
+		assert.EqualValues(t, result, convertQuestionMark(sql, "$", 1))
+	}
+}