Change runtime.interactions API to use an ofType: argument instead of…

… a block.

Summary: This simplifies the API and reduces the syntactical overhead of using it.

Reviewers: O2 Material Motion, O4 Material Apple platform reviewers, #material_motion, markwei

Reviewed By: O2 Material Motion, O4 Material Apple platform reviewers, #material_motion, markwei

Subscribers: markwei

Tags: #material_motion

Differential Revision: http://codereview.cc/D3099

src/MotionRuntime.swift

@@ -83,13 +83,21 @@ public final class MotionRuntime {
 
    Example usage:
 
-       let draggables = runtime.interactions(for: view) { $0 as? Draggable }
+       let draggables = runtime.interactions(for: view, type: Draggable.self)
    */
+  public func interactions<I>(for target: I.Target, ofType: I.Type) -> [I] where I: Interaction, I.Target: AnyObject {
+    guard let interactions = targets[ObjectIdentifier(target)] else {
+      return []
+    }
+    return interactions.flatMap { $0 as? I }
+  }
+
+  @available(*, deprecated, message: "Use interactions(for:ofType:) instead.")
   public func interactions<I>(for target: I.Target, filter: (Any) -> I?) -> [I] where I: Interaction, I.Target: AnyObject {
     guard let interactions = targets[ObjectIdentifier(target)] else {
       return []
     }
-    return interactions.flatMap(filter)
+    return interactions.flatMap { $0 as? I }
   }
 
   /**

tests/unit/MotionRuntimeTests.swift

@@ -34,7 +34,7 @@ class MotionRuntimeTests: XCTestCase {
   func testInteractionsReturnsEmptyArrayWithoutAnyAddedInteractions() {
     let runtime = MotionRuntime(containerView: UIView())
 
-    let results = runtime.interactions(for: UIView()) { $0 as? Draggable }
+    let results = runtime.interactions(for: UIView(), ofType: Draggable.self)
     XCTAssertEqual(results.count, 0)
   }
 
@@ -45,7 +45,7 @@ class MotionRuntimeTests: XCTestCase {
     runtime.add(Draggable(), to: view)
     runtime.add(Rotatable(), to: view)
 
-    let results = runtime.interactions(for: view) { $0 as? Draggable }
+    let results = runtime.interactions(for: view, ofType: Draggable.self)
     XCTAssertEqual(results.count, 1)
   }
 }