Swift: Add tests.

swift/ql/test/library-tests/dataflow/flowsources/uikit.swift

@@ -1,33 +1,82 @@
 // --- stubs ---
 
 class NSObject { }
-class NSAttributedString: NSObject {}
-class UIResponder: NSObject {}
-class UIView: UIResponder {}
-class UIControl: UIView {}
+
+struct _NSRange { }
+
+typealias NSRange = _NSRange
+
+class NSAttributedString: NSObject { }
+
+class UIResponder: NSObject { }
+
+class UIView: UIResponder { }
+
+class UIControl: UIView { }
+
+class UITextRange : NSObject {
+}
+
+protocol UITextInput {
+	func text(in range: UITextRange) -> String?
+
+  func shouldChangeText(in range: UITextRange, replacementText text: String) -> Bool
+}
+
 class UITextField: UIControl {
   var text: String? {
     get { nil }
     set { }
   }
+
   var attributedText: NSAttributedString? {
     get { nil }
     set { }
   }
+
   var placeholder: String? {
     get { nil }
     set { }
   }
 }
+
 class UISearchTextField : UITextField {
 }
 
+protocol UITextFieldDelegate {
+	func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool
+}
+
 // --- tests ---
 
-func testUITextField(textField: UITextField, searchTextField: UISearchTextField) {
+func sink(arg: Any) { }
+
+class MyTextInput : UITextInput {
+	func text(in range: UITextRange) -> String? { return nil }
+	func harmless(in range: UITextRange) -> String? { return nil }
+
+	func shouldChangeText(in range: UITextRange, replacementText text: String) -> Bool { // $ MISSING: source=local
+		sink(arg: text) // $ MISSING: tainted=
+
+		return true
+	}
+}
+
+class MyUITextFieldDelegate : UITextFieldDelegate {
+	func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool { // $ MISSING: source=local
+		sink(arg: string) // $ MISSING: tainted=
+
+		return true
+	}
+}
+
+func test(textField: UITextField, searchTextField: UISearchTextField, myTextInput: MyTextInput, range: UITextRange) {
   _ = textField.text // $ source=local
   _ = textField.attributedText // $ source=local
   _ = textField.placeholder // GOOD (not input)
   _ = textField.text?.uppercased() // $ source=local
   _ = searchTextField.text // $ source=local
+
+  _ = myTextInput.text(in: range)! // $ MISSING: source=local
+  _ = myTextInput.harmless(in: range)! // GOOD (not input)
 }