Prevent NullPointerException when parsing annotations

Author: fergal-whyte

base/src/main/java/proguard/ConfigurationParser.java

@@ -850,7 +850,7 @@ public ClassSpecification parseClassSpecificationArguments(boolean readFirstWord
         int requiredUnsetClassAccessFlags = 0;
 
         // Parse the class annotations and access modifiers until the class keyword.
-        while (!ConfigurationConstants.CLASS_KEYWORD.equals(nextWord))
+        while (!ConfigurationConstants.CLASS_KEYWORD.equals(nextWord) && !configurationEnd(true))
         {
             // Strip the negating sign, if any.
             boolean negated =

base/src/test/kotlin/proguard/ConfigurationParserTest.kt

@@ -82,6 +82,17 @@ class ConfigurationParserTest : FreeSpec({
         }
     }
 
+    "A ParseException should be thrown with invalid annotation config at the end of the file" - {
+        // This is a parse error without any further config after it.
+        val configStr = ("-keep @MyAnnotation @ThisShouldBeInterfaceKeyword")
+
+        "Then the option should throw a ParseException" {
+            shouldThrow<ParseException> {
+                configStr.asConfiguration()
+            }
+        }
+    }
+
     "Wildcard type tests" - {
         class TestConfig(
             val configOption: String,