Swift: subsume IterableDeclContext into Decl [hand-written]

Author: d10c

swift/extractor/translators/DeclTranslator.cpp

@@ -354,7 +354,7 @@ void DeclTranslator::fillTypeDecl(const swift::TypeDecl& decl, codeql::TypeDecl&
 }
 
 void DeclTranslator::fillIterableDeclContext(const swift::IterableDeclContext& decl,
-                                             codeql::IterableDeclContext& entry) {
+                                             codeql::Decl& entry) {
   entry.members = dispatcher.fetchRepeatedLabels(decl.getAllMembers());
 }
 

swift/extractor/translators/DeclTranslator.h

@@ -55,8 +55,7 @@ class DeclTranslator : public AstTranslatorBase<DeclTranslator> {
                                 codeql::AbstractFunctionDecl& entry);
   void fillOperatorDecl(const swift::OperatorDecl& decl, codeql::OperatorDecl& entry);
   void fillTypeDecl(const swift::TypeDecl& decl, codeql::TypeDecl& entry);
-  void fillIterableDeclContext(const swift::IterableDeclContext& decl,
-                               codeql::IterableDeclContext& entry);
+  void fillIterableDeclContext(const swift::IterableDeclContext& decl, codeql::Decl& entry);
   void fillVarDecl(const swift::VarDecl& decl, codeql::VarDecl& entry);
   void fillNominalTypeDecl(const swift::NominalTypeDecl& decl, codeql::NominalTypeDecl& entry);
   void fillGenericContext(const swift::GenericContext& decl, codeql::GenericContext& entry);

swift/ql/lib/codeql/swift/dataflow/ExternalFlow.qll

@@ -424,33 +424,33 @@ private Element interpretElement0(
     )
     or
     // Member functions
-    exists(NominalTypeDecl nomTypeDecl, IterableDeclContext decl, MethodDecl method |
+    exists(NominalTypeDecl nomTypeDecl, Decl decl, MethodDecl method |
       method.getName() = name and
       method = decl.getAMember() and
       nomTypeDecl.getFullName() = type and
       matchesSignature(method, signature) and
       result = method
     |
       subtypes = true and
-      decl.getNominalTypeDecl() = nomTypeDecl.getADerivedTypeDecl*()
+      decl.asNominalTypeDecl() = nomTypeDecl.getADerivedTypeDecl*()
       or
       subtypes = false and
-      decl.getNominalTypeDecl() = nomTypeDecl
+      decl.asNominalTypeDecl() = nomTypeDecl
     )
     or
     // Fields
     signature = "" and
-    exists(NominalTypeDecl nomTypeDecl, IterableDeclContext decl, FieldDecl field |
+    exists(NominalTypeDecl nomTypeDecl, Decl decl, FieldDecl field |
       field.getName() = name and
       field = decl.getAMember() and
       nomTypeDecl.getFullName() = type and
       result = field
     |
       subtypes = true and
-      decl.getNominalTypeDecl() = nomTypeDecl.getADerivedTypeDecl*()
+      decl.asNominalTypeDecl() = nomTypeDecl.getADerivedTypeDecl*()
       or
       subtypes = false and
-      decl.getNominalTypeDecl() = nomTypeDecl
+      decl.asNominalTypeDecl() = nomTypeDecl
     )
   )
 }

swift/ql/lib/codeql/swift/elements/decl/Decl.qll

@@ -1,5 +1,22 @@
 private import codeql.swift.generated.decl.Decl
+private import codeql.swift.elements.decl.NominalTypeDecl
+private import codeql.swift.elements.decl.ExtensionDecl
 
 class Decl extends Generated::Decl {
   override string toString() { result = super.toString() }
+
+  /**
+   * Gets the `NominalTypeDecl` corresponding to this `Decl`, if any. This
+   * resolves an `ExtensionDecl` to the `NominalTypeDecl` that it extends.
+   */
+  NominalTypeDecl asNominalTypeDecl() {
+    result = this
+    or
+    result = this.(ExtensionDecl).getExtendedTypeDecl()
+  }
+
+  /**
+   * Gets the declaration that declares this declaration as a member, if any.
+   */
+  Decl getDeclaringDecl() { this = result.getAMember() }
 }

swift/ql/lib/codeql/swift/elements/decl/IterableDeclContext.qll

@@ -1,6 +1,6 @@
 private import swift
 
-private Decl getAMember(IterableDeclContext ctx) {
+private Decl getAMember(Decl ctx) {
   ctx.getAMember() = result
   or
   exists(VarDecl var |

swift/ql/lib/codeql/swift/elements/decl/MethodDecl.qll

@@ -1,6 +1,6 @@
 private import codeql.swift.generated.decl.VarDecl
 private import codeql.swift.elements.expr.DeclRefExpr
-private import codeql.swift.elements.decl.IterableDeclContext
+private import codeql.swift.elements.decl.Decl
 
 class VarDecl extends Generated::VarDecl {
   override string toString() { result = this.getName() }
@@ -9,5 +9,5 @@ class VarDecl extends Generated::VarDecl {
 }
 
 class FieldDecl extends VarDecl {
-  FieldDecl() { this = any(IterableDeclContext ctx).getAMember() }
+  FieldDecl() { this = any(Decl ctx).getAMember() }
 }

swift/ql/lib/codeql/swift/elements/decl/VarDecl.qll

@@ -77,6 +77,7 @@ class Type(Element):
 @group("decl")
 class Decl(AstNode):
     module: "ModuleDecl"
+    members: list["Decl"] | child
 
 @group("expr")
 class Expr(AstNode):
@@ -95,14 +96,10 @@ class Stmt(AstNode):
 class GenericContext(Element):
     generic_type_params: list["GenericTypeParamDecl"] | child
 
-@group("decl")
-class IterableDeclContext(Element):
-    members: list[Decl] | child
-
 class EnumCaseDecl(Decl):
     elements: list["EnumElementDecl"]
 
-class ExtensionDecl(GenericContext, IterableDeclContext, Decl):
+class ExtensionDecl(GenericContext, Decl):
     extended_type_decl: "NominalTypeDecl"
     protocols: list["ProtocolDecl"]
 
@@ -303,7 +300,7 @@ class ConcreteVarDecl(VarDecl):
 class GenericTypeParamDecl(AbstractTypeParamDecl):
     pass
 
-class NominalTypeDecl(GenericTypeDecl, IterableDeclContext):
+class NominalTypeDecl(GenericTypeDecl):
     type: Type
 
 class OpaqueTypeDecl(GenericTypeDecl):