Swift: CFG for 'yield'.

Author: MathiasVP

swift/ql/lib/codeql/swift/controlflow/internal/ControlFlowGraphImpl.qll

@@ -203,6 +203,14 @@ module Stmts {
     }
   }
 
+  private class YieldStmtTree extends AstStandardPostOrderTree {
+    override YieldStmt ast;
+
+    final override ControlFlowElement getChildElement(int i) {
+      result.asAstNode() = ast.getResult(i).getFullyConverted()
+    }
+  }
+
   private class FailTree extends AstLeafTree {
     override FailStmt ast;
   }

swift/ql/test/library-tests/controlflow/graph/Cfg.expected

@@ -5139,6 +5139,11 @@ cfg.swift:
 #  394| enter set
 #-----|  -> set
 
+#  394| exit (unnamed function decl)
+
+#  394| exit (unnamed function decl) (normal)
+#-----|  -> exit (unnamed function decl)
+
 #  394| exit get
 
 #  394| exit get (normal)
@@ -5156,6 +5161,9 @@ cfg.swift:
 
 #  394| value
 
+#  394| yield ...
+#-----|  -> exit (unnamed function decl) (normal)
+
 #  395| deinit
 #-----|  -> self