Predicate locator added in IOSDriver, IOSElement, and iOSFindBy

src/main/java/io/appium/java_client/ios/IOSDriver.java

@@ -19,6 +19,7 @@
 import static io.appium.java_client.MobileCommand.prepareArguments;
 
 import io.appium.java_client.AppiumDriver;
+import io.appium.java_client.FindsByIosNSPredicate;
 import io.appium.java_client.FindsByIosUIAutomation;
 import io.appium.java_client.ios.internal.JsonToIOSElementConverter;
 import io.appium.java_client.remote.MobilePlatform;
@@ -50,7 +51,7 @@
 public class IOSDriver<T extends WebElement>
     extends AppiumDriver<T>
     implements IOSDeviceActionShortcuts,
-        FindsByIosUIAutomation<T>, LocksIOSDevice {
+        FindsByIosUIAutomation<T>, FindsByIosNSPredicate<T>, LocksIOSDevice {
 
     private static final String IOS_PLATFORM = MobilePlatform.IOS;
 

src/main/java/io/appium/java_client/ios/IOSElement.java

@@ -16,9 +16,11 @@
 
 package io.appium.java_client.ios;
 
+import io.appium.java_client.FindsByIosNSPredicate;
 import io.appium.java_client.FindsByIosUIAutomation;
 import io.appium.java_client.MobileElement;
 
 public class IOSElement extends MobileElement
-    implements FindsByIosUIAutomation<MobileElement> {
+    implements FindsByIosUIAutomation<MobileElement>,
+        FindsByIosNSPredicate<MobileElement> {
 }

src/main/java/io/appium/java_client/pagefactory/bys/builder/Strategies.java

@@ -40,6 +40,15 @@ enum Strategies {
             return super.getBy(annotation);
         }
     },
+    BYPREDICATE("predicate") {
+        @Override By getBy(Annotation annotation) {
+            String value = getValue(annotation, this);
+            if (annotation.annotationType().equals(iOSFindBy.class)) {
+                return MobileBy.iOSNsPredicateString(value);
+            }
+            return super.getBy(annotation);
+        }
+    },
     BYACCESSABILITY("accessibility") {
         @Override By getBy(Annotation annotation) {
             return MobileBy.AccessibilityId(getValue(annotation, this));

src/main/java/io/appium/java_client/pagefactory/iOSFindBy.java

@@ -27,7 +27,7 @@
  * element or a list of elements. Used in conjunction with
  * {@link org.openqa.selenium.support.PageFactory}
  * this allows users to quickly and easily create PageObjects.
- * using iOS UI selectors, accessibility, id, name, class name, tag and xpath
+ * using iOS UI selectors, predicate, accessibility, id, name, class name, tag and xpath
  */
 @Retention(RetentionPolicy.RUNTIME) @Target({ElementType.FIELD, ElementType.TYPE})
 public @interface iOSFindBy {
@@ -38,6 +38,13 @@
      */
     String uiAutomator() default "";
 
+    /**
+     * It is a properly formatted string for an NSPredicate.
+     * {@link "https://developer.apple.com/library/content/documentation/Cocoa/
+     * Conceptual/Predicates/AdditionalChapters/Introduction.html"}
+     */
+    String predicate() default "";
+
     /**
      * It an UI automation accessibility Id which is a convenient to iOS.
      * About iOS accessibility

src/test/java/io/appium/java_client/ios/IOSElementTest.java

@@ -34,6 +34,12 @@ public class IOSElementTest extends BaseIOSTest {
             .findElementByIosUIAutomation(".elements().withName(\"Answer\")").getText(), null);
     }
 
+    @Test public void findByPredicateTest() {
+        assertNotEquals(((IOSElement) driver.findElementsByClassName("UIAWindow")
+            .get(1))
+            .findElementByIosNsPredicate("label CONTAINS 'Compute'").getText(), null);
+    }
+
     @Test public void setValueNunslaughterTest() {
         IOSElement slider = (IOSElement) driver.findElementByClassName("UIASlider");
         slider.setValue("0%");

src/test/java/io/appium/java_client/ios/IOSSearchingTest.java

@@ -39,4 +39,14 @@ public class IOSSearchingTest extends BaseIOSTest {
                 .findElementsByIosUIAutomation(".elements().withName(\"Answer\")")
                 .size(), 0);
     }
+
+    @Test public void findByPredicateTest() {
+        assertNotEquals(driver
+            .findElementByIosNsPredicate("label CONTAINS 'Compute'")
+            .getText(), null);
+        assertNotEquals(driver
+                .findElementsByIosNsPredicate("label CONTAINS 'Compute'")
+                .size(), 0);
+    }
+
 }

src/test/java/io/appium/java_client/pagefactory_tests/IOSPageFactoryTest.java

@@ -63,6 +63,8 @@ public class IOSPageFactoryTest {
 
     @iOSFindBy(uiAutomator = ".elements()[0]") private List<WebElement> iosUIAutomatorButtons;
 
+    @iOSFindBy(predicate = "label CONTAINS 'Compute'") private List<WebElement> iosPredicateButtons;
+
     @iOSFindBy(uiAutomator = ".elements()[0]") @AndroidFindBy(className = "android.widget.TextView")
     private List<WebElement> androidOriOsTextViews;
 
@@ -87,6 +89,8 @@ public class IOSPageFactoryTest {
 
     @iOSFindBy(uiAutomator = ".elements()[0]") private WebElement iosUIAutomatorButton;
 
+    @iOSFindBy(predicate = "label CONTAINS 'Compute'") private WebElement iosPredicateButton;
+
     @AndroidFindBy(className = "android.widget.TextView") @iOSFindBy(uiAutomator = ".elements()[0]")
     private WebElement androidOriOsTextView;
 
@@ -216,6 +220,14 @@ public class IOSPageFactoryTest {
         assertNotEquals(null, iosUIAutomatorButton.getText());
     }
 
+    @Test public void iosFindByPredicateElementsTest() {
+        assertNotEquals(0, iosPredicateButtons.size());
+    }
+
+    @Test public void iosFindByPredicateElementTest() {
+        assertNotEquals(null, iosPredicateButton.getText());
+    }
+
     @Test public void areMobileElementsTest() {
         assertNotEquals(0, mobileButtons.size());
     }