Swift: Add an AST class for possible method declarations.

Author: MathiasVP

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

@@ -0,0 +1,24 @@
+private import swift
+
+private Decl getAMember(IterableDeclContext ctx) {
+  ctx.getAMember() = result
+  or
+  exists(VarDecl var |
+    ctx.getAMember() = var and
+    var.getAnAccessorDecl() = result
+  )
+}
+
+class MethodDecl extends AbstractFunctionDecl {
+  MethodDecl() {
+    this = getAMember(any(ClassDecl c))
+    or
+    this = getAMember(any(StructDecl c))
+    or
+    this = getAMember(any(ExtensionDecl c))
+    or
+    this = getAMember(any(EnumDecl c))
+    or
+    this = getAMember(any(ProtocolDecl c))
+  }
+}

swift/ql/lib/swift.qll

@@ -2,3 +2,4 @@
 
 import codeql.swift.elements
 import codeql.swift.elements.expr.LogicalOperation
+import codeql.swift.elements.decl.MethodDecl