opt selector start err msg

Author: DQinYuan

src/main/antlr4/QLexer.g4

@@ -15,6 +15,8 @@ lexer grammar QLexer;
     }
 
     protected void consumeSelectorVariable() { }
+
+    protected void throwScannerException(String lexeme, String reason) { }
 }
 
 // lexer
@@ -372,7 +374,7 @@ SELECTOR_START: ('${' | '$[' | '#{' | '#[') {
     if (getSelectorStart().equals(getText())) {
         pushMode(SelectorVariable);
     } else {
-        setType(CATCH_ALL);
+        throwScannerException(getText(), "invalid selector start, expect '" + getSelectorStart() + "'");
     }
 };
 

src/main/java/com/alibaba/qlexpress4/aparser/QLExtendLexer.java

@@ -46,13 +46,7 @@ protected void consumeSelectorVariable() {
             int curChInt = _input.LA(1);
             if (curChInt == Token.EOF || curChInt == '\n') {
                 // mismatch
-                throw QLException.reportScannerErr(script,
-                    this._tokenStartCharIndex,
-                    this._tokenStartLine,
-                    this._tokenStartCharPositionInLine,
-                    t.toString(),
-                    QLErrorCodes.SYNTAX_ERROR.name(),
-                    "unterminated selector");
+                throwScannerException(t.toString(), "unterminated selector");
             }
             char curCh = (char)curChInt;
             t.append(curCh);
@@ -70,6 +64,17 @@ protected void consumeSelectorVariable() {
         }
     }
 
+    @Override
+    protected void throwScannerException(String lexeme, String reason) {
+        throw QLException.reportScannerErr(script,
+            this._tokenStartCharIndex,
+            this._tokenStartLine,
+            this._tokenStartCharPositionInLine,
+            lexeme,
+            QLErrorCodes.SYNTAX_ERROR.name(),
+            reason);
+    }
+    
     private boolean checkEndsWith(StringBuilder sb, String suffix) {
         int suffixLength = suffix.length();
         int sbLength = sb.length();

src/test/java/com/alibaba/qlexpress4/Express4RunnerTest.java

@@ -1140,10 +1140,8 @@ public void customSelectorWhenNoCloseTest() {
         Express4Runner express4Runner =
             new Express4Runner(InitOptions.builder().selectorStart("#[").selectorEnd("]").build());
 
-        Map<String, Object> context = new HashMap<>();
-        context.put("0", "World");
-        
         assertErrorCode(express4Runner, "'Hello ' + #[0grg", QLErrorCodes.SYNTAX_ERROR.name());
+        assertErrorCode(express4Runner, "'Hello ' + ${pl}", QLErrorCodes.SYNTAX_ERROR.name());
     }
 
     private void assertResultEquals(Express4Runner express4Runner, String script, Object expect) {