refactor away the ComparisonOp ast class

Author: erik-krogh

ql/src/codeql_ql/ast/Ast.qll

@@ -1153,23 +1153,6 @@ class Disjunction extends TDisjunction, AstNode, Formula {
   }
 }
 
-/**
- * A comparison operator, such as `<` or `=`.
- */
-class ComparisonOp extends TComparisonOp, AstNode {
-  QL::Compop op;
-
-  ComparisonOp() { this = TComparisonOp(op) }
-
-  /**
-   * Gets a string representing the operator.
-   * E.g. "<" or "=".
-   */
-  ComparisonSymbol getSymbol() { result = op.getValue() }
-
-  override string getAPrimaryQlClass() { result = "ComparisonOp" }
-}
-
 /**
  * A literal expression, such as `6` or `true` or `"foo"`.
  */
@@ -1266,10 +1249,7 @@ class ComparisonFormula extends TComparisonFormula, Formula {
   Expr getAnOperand() { result in [this.getLeftOperand(), this.getRightOperand()] }
 
   /** Gets the operator of this comparison. */
-  ComparisonOp getOperator() { toQL(result) = comp.getChild() }
-
-  /** Gets the symbol of this comparison (as a string). */
-  ComparisonSymbol getSymbol() { result = this.getOperator().getSymbol() }
+  ComparisonSymbol getOperator() { result = comp.getChild().getValue() }
 
   override string getAPrimaryQlClass() { result = "ComparisonFormula" }
 
@@ -1279,8 +1259,6 @@ class ComparisonFormula extends TComparisonFormula, Formula {
     pred = directMember("getLeftOperand") and result = this.getLeftOperand()
     or
     pred = directMember("getRightOperand") and result = this.getRightOperand()
-    or
-    pred = directMember("getOperator") and result = this.getOperator()
   }
 }
 

ql/src/codeql_ql/ast/internal/AstNodes.qll

@@ -22,7 +22,6 @@ newtype TAstNode =
   TDisjunction(QL::Disjunction disj) or
   TConjunction(QL::Conjunction conj) or
   TComparisonFormula(QL::CompTerm comp) or
-  TComparisonOp(QL::Compop op) or
   TQuantifier(QL::Quantified quant) or
   TFullAggregate(QL::Aggregate agg) { agg.getChild(_) instanceof QL::FullAggregateBody } or
   TExprAggregate(QL::Aggregate agg) { agg.getChild(_) instanceof QL::ExprAggregateBody } or
@@ -91,7 +90,6 @@ private QL::AstNode toQLFormula(AST::AstNode n) {
   n = TConjunction(result) or
   n = TDisjunction(result) or
   n = TComparisonFormula(result) or
-  n = TComparisonOp(result) or
   n = TQuantifier(result) or
   n = TFullAggregate(result) or
   n = TIdentifier(result) or

ql/src/queries/performance/ClassPredicateDoesntMentionThis.ql

@@ -25,7 +25,7 @@ predicate usesThis(ClassPredicate pred) {
 
 predicate isLiteralComparison(ComparisonFormula eq) {
   exists(Expr lhs, Expr rhs |
-    eq.getSymbol() = "=" and
+    eq.getOperator() = "=" and
     eq.getAnOperand() = lhs and
     eq.getAnOperand() = rhs and
     (

ql/src/queries/performance/PrefixSuffixEquality.ql

@@ -29,7 +29,7 @@ class SuffixPredicateCall extends Call {
 }
 
 class EqFormula extends ComparisonFormula {
-  EqFormula() { this.getSymbol() = "=" }
+  EqFormula() { this.getOperator() = "=" }
 }
 
 bindingset[s]

ql/src/queries/performance/TransitiveStep.ql

@@ -78,7 +78,7 @@ predicate transitivePred(Predicate p, AstNode tc) {
     or
     exists(ComparisonFormula eq, Call c |
       body = eq and
-      eq.getSymbol() = "=" and
+      eq.getOperator() = "=" and
       transitiveCall(c, tc) and
       getArg(c, _) instanceof Identifier and
       eq.getAnOperand() = c and
@@ -141,7 +141,7 @@ predicate valueStep(Expr e1, Expr e2) {
   )
   or
   exists(ComparisonFormula eq |
-    eq.getSymbol() = "=" and
+    eq.getOperator() = "=" and
     eq.getAnOperand() = e1 and
     eq.getAnOperand() = e2 and
     e1 != e2

ql/src/queries/style/ToStringInQueryLogic.ql

@@ -227,7 +227,7 @@ module DataFlow {
     )
     or
     exists(ComparisonFormula eq |
-      eq.getSymbol() = "=" and
+      eq.getOperator() = "=" and
       eq.getAnOperand() = e1 and
       eq.getAnOperand() = e2 and
       e1 != e2