DefineStatementLexer: improve backslash escape in quotes handling

RELEASE_NOTES.md

@@ -1,5 +1,6 @@
 # Unreleased
 
+  - Fix DefinedAttributeTemplateEngine lexer bug swallowing single-quoted text with escapes (#1906)
   - ANTLr 4.10.1
   - GSON 2.9.0 fixes CVE-2022-25647
 

core/src/main/antlr4/org/jdbi/v3/core/internal/lexer/DefineStatementLexer.g4

@@ -13,21 +13,19 @@
  */
 lexer grammar DefineStatementLexer;
 
-fragment QUOTE: '\'' ;
-fragment ESCAPE: '\\' ;
-fragment ESCAPE_QUOTE: ESCAPE QUOTE ;
+fragment ESCAPE_IN_QUOTE: '\\' ['\\] ;
 fragment DOUBLE_QUOTE: '"' ;
 fragment LT: '<' ;
 fragment GT: '>' ;
 fragment NAME: JAVA_LETTER | [0-9];
 
-/* Lovingly lifted from https://github.com/antlr/grammars-v4/blob/master/java/JavaLexer.g4 */
+/* Lovingly lifted from https://github.com/antlr/grammars-v4/blob/master/java/java/JavaLexer.g4 */
 fragment JAVA_LETTER : [a-zA-Z$_] | ~[\u0000-\u007F\uD800-\uDBFF] | [\uD800-\uDBFF] [\uDC00-\uDFFF];
 
 COMMENT: '/*' .*? '*/' | '--' ~('\r' | '\n')* | '//' ~('\r' | '\n')*;
-QUOTED_TEXT: QUOTE (ESCAPE_QUOTE | ~'\'')* QUOTE;
+QUOTED_TEXT: '\'' (~['\\\r\n] | ESCAPE_IN_QUOTE)* '\'';
 DOUBLE_QUOTED_TEXT: DOUBLE_QUOTE (~'"')+ DOUBLE_QUOTE;
-ESCAPED_TEXT : ESCAPE . ;
+ESCAPED_TEXT : '\\' . ;
 
 DEFINE: LT (NAME)+ GT;
 

core/src/test/java/org/jdbi/v3/core/statement/DefinedAttributeTemplateEngineTest.java

@@ -0,0 +1,48 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jdbi.v3.core.statement;
+
+import org.jdbi.v3.core.Handle;
+import org.jdbi.v3.core.junit5.H2DatabaseExtension;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class DefinedAttributeTemplateEngineTest {
+
+    @RegisterExtension
+    public H2DatabaseExtension h2Extension = H2DatabaseExtension.instance()
+            .withConfig(SqlStatements.class, st -> st.setTemplateEngine(new DefinedAttributeTemplateEngine()));
+
+    String renderedSql;
+
+    @Test
+    public void testBackslash1906() {
+        final Handle handle = h2Extension.getSharedHandle();
+        final SqlLogger captureSql = new SqlLogger() {
+            @Override
+            public void logAfterExecution(final StatementContext context) {
+                renderedSql = context.getRenderedSql();
+            }
+        };
+        handle.setSqlLogger(captureSql);
+        final String backslashSql = "SELECT '\\\\' = '\\\\'";
+        handle
+                .createQuery(backslashSql)
+                .mapTo(boolean.class)
+                .one();
+        assertThat(renderedSql).isEqualTo(backslashSql);
+    }
+}