private @NotNull ProblemDescriptor createSubstringToCharAtProblemDescriptor(@NotNull PsiMethodCallExpression call, @NotNull PsiElement anchor) {
      final String converted = SubstringToCharAtQuickFix.getTargetString(call, PsiElement::getText);
      assert converted != null : "Message cannot be null";

      return myManager.createProblemDescriptor(anchor,
                                               InspectionGadgetsBundle.message("inspection.x.call.can.be.replaced.with.y", "charAt"),
                                               new SubstringToCharAtQuickFix(getOutermostEquals(call).getText(), converted, true),
                                               ProblemHighlightType.GENERIC_ERROR_OR_WARNING, myIsOnTheFly);
    }
private @NotNull ProblemDescriptor createSubstringToCharAtProblemDescriptor(@NotNull PsiMethodCallExpression call, @NotNull PsiElement anchor)