Refactor NumericLiteral and UserDefinedLiteral classes for improved clarity and functionality

Author: mbaluda

cpp/common/src/codingstandards/cpp/Cpp14Literal.qll

@@ -11,12 +11,7 @@ module Cpp14Literal {
   abstract class NumericLiteral extends StandardLibrary::Literal {
     NumericLiteral() {
       // exclude user-defined literals as they define custom suffixes
-      not exists(StandardLibrary::FunctionCall fc |
-        this = fc.getArgument(0) and
-        fc.getTarget() instanceof UserDefinedLiteral
-      ) and
-      // exclude literals derived from template instantiations
-      not this.isFromTemplateInstantiation(_)
+      not this instanceof UserDefinedLiteral 
     }
   }
 

cpp/common/src/codingstandards/cpp/UserDefinedLiteral.qll

@@ -4,8 +4,8 @@
 
 import cpp
 
-class UserDefinedLiteral extends Function {
-  UserDefinedLiteral() {
+class UserDefinedLiteralDeclaration extends Function {
+  UserDefinedLiteralDeclaration() {
     // We use the '?' in this regexp because CodeQL CLI 2.4.6 and earlier reported these operators
     // using a single ", i.e `operator "`. This has been fixed in 2.5.9 (at the latest), but I
     // don't know if upgraded older databases will still have the broken version in. I've therefore
@@ -16,3 +16,12 @@ class UserDefinedLiteral extends Function {
   /** Holds if `this` has a compliant suffix. */
   predicate hasCompliantSuffix() { this.getName().regexpMatch("operator \"\"?_\\p{Alpha}+") }
 }
+
+class UserDefinedLiteral extends Literal {
+  UserDefinedLiteral() {
+    exists(FunctionCall fc |
+      this = fc.getArgument(0) and
+      fc.getTarget() instanceof UserDefinedLiteralDeclaration
+    )
+  }
+}

cpp/common/src/codingstandards/cpp/rules/unsignedintegerliteralsnotappropriatelysuffixed/UnsignedIntegerLiteralsNotAppropriatelySuffixed.qll

@@ -26,6 +26,8 @@ query predicate problems(Cpp14Literal::NumericLiteral nl, string message) {
     nl.getType().getUnspecifiedType().(IntegralType).isUnsigned() and
     // The literal already has a `u` or `U` suffix.
     not nl.getValueText().regexpMatch(".*[lL]*[uU][lL]*") and
+    // exclude literals derived from template instantiations
+    not nl.isFromTemplateInstantiation(_) and
     message = literalKind + " literal is an unsigned integer but does not include a 'U' suffix."
   )
 }