Fixed issue: Invalid escape sequences in string literals not raising errors (e.g. \q)

core/src/main/java/org/luaj/vm2/compiler/LexState.java

@@ -552,9 +552,12 @@ public class LexState extends Constants {
 							continue;
 						}
 						default: {
-							if (!isdigit(current))
-								save_and_next(); /* handles \\, \", \', and \? */
-							else { /* \xxx */
+							if (!isdigit(current)) {
+								if (current == '\\' || current == '"' || current == '\'')
+									save_and_next();
+								else
+									lexerror("invalid escape sequence", TK_STRING);
+							} else { /* \xxx */
 								int i = 0;
 								c = 0;
 								do {
@@ -2150,4 +2153,4 @@ public class LexState extends Constants {
 
 	/* }====================================================================== */
 
-}
+}

jse/src/test/java/org/luaj/vm2/compiler/SimpleTests.java

@@ -4,6 +4,7 @@ import junit.framework.TestCase;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LuaDouble;
 import org.luaj.vm2.LuaInteger;
+import org.luaj.vm2.LuaError;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.libs.jse.JsePlatform;
 
@@ -61,7 +62,17 @@ public class SimpleTests extends TestCase {
 			"print( 2 )\n";
 		doTest( s );
 	}
-	
+
+	public void testInvalidStringEscapeFails() {
+		try {
+			globals.load("local s = \"bad\\qescape\"\nprint(s)\n", "script");
+			fail("expected invalid escape sequence");
+		} catch (LuaError e) {
+			assertTrue("unexpected error: " + e.getMessage(),
+					e.getMessage().indexOf("invalid escape sequence") >= 0);
+		}
+	}
+
 	public void testInlineTable() {
 		String s = "A = {g=10}\n"+
 			"print( A )\n";