MAT-7995 filter out err msg when define lacks name

src/main/java/gov/cms/mat/cql_elm_translation/service/filters/CqlTranslatorExceptionFilter.java

@@ -48,11 +48,17 @@ public List<CqlCompilerException> filter() {
 
     filteredList = filterBySyntax(filteredCqlTranslatorExceptions);
     if (CollectionUtils.isNotEmpty(filteredList)) {
-      newList.addAll(filteredList);
+      newList.addAll(filterOutCustomErrors(filteredList));
     }
     return newList;
   }
 
+  /*
+   * MAT-7995: error: "No Viable Input at 'define :'"
+   * should be customized as: "Definition is missing a name."
+   * This is done in cql-antlr-parse, so on the frontend we don't want a duplicate error message
+   * therefore we are filtering it out here.
+   */
   private List<CqlCompilerException> filterOutWarnings() {
     if (showWarnings) {
       return cqlTranslatorExceptions;
@@ -111,4 +117,14 @@ private List<CqlCompilerException> filterBySyntax(
                     .contains("org.cqframework.cql.cql2elm.CqlSyntaxException"))
         .toList();
   }
+
+  private List<CqlCompilerException> filterOutCustomErrors(
+      List<CqlCompilerException> filteredCqlTranslatorExceptions) {
+    return filteredCqlTranslatorExceptions.stream()
+        .filter(
+            cqlCompilerException ->
+                !"no viable alternative at input 'define :'"
+                    .equalsIgnoreCase(cqlCompilerException.getMessage()))
+        .toList();
+  }
 }