ruby: drop the CallableCfgNode classes

Author: alexrford

ruby/ql/lib/codeql/ruby/controlflow/CfgNodes.qll

@@ -751,23 +751,4 @@ module ExprNodes {
     /** Gets a pair of this hash literal. */
     PairCfgNode getAKeyValuePair() { result = this.getAnArgument() }
   }
-
-  private class CallableExprChildMapping extends ExprChildMapping, Callable {
-    // TODO: parameters?, callable body?
-    override predicate relevantChild(AstNode n) { none() }
-  }
-
-  /** A control-flow node that wraps a `Callable` AST expression. */
-  class CallableCfgNode extends ExprCfgNode {
-    override CallableExprChildMapping e;
-
-    override Callable getExpr() { result = super.getExpr() }
-  }
-
-  /** A control-flow node that wraps a `MethodBase` AST expression. */
-  class MethodBaseCfgNode extends CallableCfgNode {
-    MethodBaseCfgNode() { super.getExpr() instanceof MethodBase }
-
-    override MethodBase getExpr() { result = super.getExpr() }
-  }
 }

ruby/ql/lib/codeql/ruby/experimental/Rbi.qll

@@ -231,13 +231,13 @@ module Rbi {
     /**
      * Gets the method whose type signature is defined by this call.
      */
-    ExprNodes::MethodBaseCfgNode getAssociatedMethod() {
+    Method getAssociatedMethod() {
       result =
-        min(ExprNodes::MethodBaseCfgNode m, int i |
-          methodSignatureSuccessorNodeRanked(this, m, i)
+        min(ExprCfgNode methodCfgNode, int i |
+          methodSignatureSuccessorNodeRanked(this, methodCfgNode, i)
         |
-          m order by i
-        )
+          methodCfgNode order by i
+        ).getExpr()
     }
 
     /**
@@ -397,13 +397,13 @@ module Rbi {
 
     private SignatureCall getOuterMethodSignatureCall() { this = result.getAParameterType() }
 
-    private ExprNodes::MethodBaseCfgNode getAssociatedMethod() {
+    private Method getAssociatedMethod() {
       result = this.getOuterMethodSignatureCall().(MethodSignatureCall).getAssociatedMethod()
     }
 
     /** Gets the parameter to which this type applies. */
     NamedParameter getParameter() {
-      result = this.getAssociatedMethod().getExpr().getAParameter() and
+      result = this.getAssociatedMethod().getAParameter() and
       result.getName() = this.getKey().getConstantValue().getStringlikeValue()
     }
   }

ruby/ql/test/library-tests/experimental/Rbi.ql

@@ -43,9 +43,7 @@ query predicate procParameterTypes(
   pc = prtc.getProcCall()
 }
 
-query predicate sigMethods(MethodSignatureCall sig, ExprNodes::MethodBaseCfgNode m) {
-  m = sig.getAssociatedMethod()
-}
+query predicate sigMethods(MethodSignatureCall sig, Method m) { m = sig.getAssociatedMethod() }
 
 query predicate sigAttrReaders(MethodSignatureCall sig, ExprNodes::MethodCallCfgNode attr_reader) {
   attr_reader = sig.getAssociatedAttrReaderCall()