Merge pull request square#1046 from square/dimitris/leak-fix

Fix potential leak with deferred request creators

Author: dnkoutso

picasso/src/main/java/com/squareup/picasso/DeferredRequestCreator.java

@@ -61,6 +61,7 @@ class DeferredRequestCreator implements ViewTreeObserver.OnPreDrawListener {
   }
 
   void cancel() {
+    creator.clearTag();
     callback = null;
     ImageView target = this.target.get();
     if (target == null) {
@@ -72,4 +73,8 @@ void cancel() {
     }
     vto.removeOnPreDrawListener(this);
   }
+
+  Object getTag() {
+    return creator.getTag();
+  }
 }

picasso/src/main/java/com/squareup/picasso/Picasso.java

@@ -227,14 +227,28 @@ public void cancelRequest(RemoteViews remoteViews, int viewId) {
    */
   public void cancelTag(Object tag) {
     checkMain();
+    if (tag == null) {
+      throw new IllegalArgumentException("Cannot cancel requests with null tag.");
+    }
+
     List<Action> actions = new ArrayList<Action>(targetToAction.values());
     //noinspection ForLoopReplaceableByForEach
     for (int i = 0, n = actions.size(); i < n; i++) {
       Action action = actions.get(i);
-      if (action.getTag().equals(tag)) {
+      if (tag.equals(action.getTag())) {
         cancelExistingRequest(action.getTarget());
       }
     }
+
+    List<DeferredRequestCreator> deferredRequestCreators =
+        new ArrayList<DeferredRequestCreator>(targetToDeferredRequestCreator.values());
+    //noinspection ForLoopReplaceableByForEach
+    for (int i = 0, n = deferredRequestCreators.size(); i < n; i++) {
+      DeferredRequestCreator deferredRequestCreator = deferredRequestCreators.get(i);
+      if (tag.equals(deferredRequestCreator.getTag())) {
+        deferredRequestCreator.cancel();
+      }
+    }
   }
 
   /**

picasso/src/main/java/com/squareup/picasso/RequestCreator.java

@@ -206,6 +206,17 @@ RequestCreator unfit() {
     return this;
   }
 
+  /** Internal use only. Used by {@link DeferredRequestCreator}. */
+  RequestCreator clearTag() {
+    this.tag = null;
+    return this;
+  }
+
+  /** Internal use only. Used by {@link DeferredRequestCreator}. */
+  Object getTag() {
+    return tag;
+  }
+
   /** Resize the image to the specified dimension size. */
   public RequestCreator resizeDimen(int targetWidthResId, int targetHeightResId) {
     Resources resources = picasso.context.getResources();

picasso/src/test/java/com/squareup/picasso/DeferredRequestCreatorTest.java

@@ -46,26 +46,26 @@ public class DeferredRequestCreatorTest {
 
   @Captor ArgumentCaptor<Action> actionCaptor;
 
-  @Before public void setUp() throws Exception {
+  @Before public void setUp() {
     initMocks(this);
   }
 
-  @Test public void initAttachesLayoutListener() throws Exception {
+  @Test public void initAttachesLayoutListener() {
     ImageView target = mockFitImageViewTarget(true);
     ViewTreeObserver observer = target.getViewTreeObserver();
     DeferredRequestCreator request = new DeferredRequestCreator(mock(RequestCreator.class), target);
     verify(observer).addOnPreDrawListener(request);
   }
 
-  @Test public void cancelRemovesLayoutListener() throws Exception {
+  @Test public void cancelRemovesLayoutListener() {
     ImageView target = mockFitImageViewTarget(true);
     ViewTreeObserver observer = target.getViewTreeObserver();
     DeferredRequestCreator request = new DeferredRequestCreator(mock(RequestCreator.class), target);
     request.cancel();
     verify(observer).removeOnPreDrawListener(request);
   }
 
-  @Test public void cancelClearsCallback() throws Exception {
+  @Test public void cancelClearsCallback() {
     ImageView target = mockFitImageViewTarget(true);
     Callback callback = mockCallback();
     DeferredRequestCreator request =
@@ -75,7 +75,16 @@ public class DeferredRequestCreatorTest {
     assertThat(request.callback).isNull();
   }
 
-  @Test public void onLayoutSkipsIfTargetIsNull() throws Exception {
+  @Test public void cancelClearsTag() {
+    ImageView target = mockFitImageViewTarget(true);
+    RequestCreator creator = mock(RequestCreator.class);
+    when(creator.getTag()).thenReturn("TAG");
+    DeferredRequestCreator request = new DeferredRequestCreator(creator, target);
+    request.cancel();
+    verify(creator).clearTag();
+  }
+
+  @Test public void onLayoutSkipsIfTargetIsNull() {
     ImageView target = mockFitImageViewTarget(true);
     RequestCreator creator = mock(RequestCreator.class);
     DeferredRequestCreator request = new DeferredRequestCreator(creator, target);
@@ -87,7 +96,7 @@ public class DeferredRequestCreatorTest {
     verifyNoMoreInteractions(viewTreeObserver);
   }
 
-  @Test public void onLayoutSkipsIfViewTreeObserverIsDead() throws Exception {
+  @Test public void onLayoutSkipsIfViewTreeObserverIsDead() {
     ImageView target = mockFitImageViewTarget(false);
     RequestCreator creator = mock(RequestCreator.class);
     DeferredRequestCreator request = new DeferredRequestCreator(creator, target);
@@ -99,7 +108,7 @@ public class DeferredRequestCreatorTest {
     verifyZeroInteractions(creator);
   }
 
-  @Test public void waitsForAnotherLayoutIfWidthOrHeightIsZero() throws Exception {
+  @Test public void waitsForAnotherLayoutIfWidthOrHeightIsZero() {
     ImageView target = mockFitImageViewTarget(true);
     when(target.getWidth()).thenReturn(0);
     when(target.getHeight()).thenReturn(0);
@@ -110,7 +119,7 @@ public class DeferredRequestCreatorTest {
     verifyZeroInteractions(creator);
   }
 
-  @Test public void cancelSkipsWithNullTarget() throws Exception {
+  @Test public void cancelSkipsWithNullTarget() {
     ImageView target = mockFitImageViewTarget(true);
     RequestCreator creator = mock(RequestCreator.class);
     DeferredRequestCreator request = new DeferredRequestCreator(creator, target);
@@ -119,15 +128,15 @@ public class DeferredRequestCreatorTest {
     verify(target.getViewTreeObserver(), never()).removeOnPreDrawListener(request);
   }
 
-  @Test public void cancelSkipsIfViewTreeObserverIsDead() throws Exception {
+  @Test public void cancelSkipsIfViewTreeObserverIsDead() {
     ImageView target = mockFitImageViewTarget(false);
     RequestCreator creator = mock(RequestCreator.class);
     DeferredRequestCreator request = new DeferredRequestCreator(creator, target);
     request.cancel();
     verify(target.getViewTreeObserver(), never()).removeOnPreDrawListener(request);
   }
 
-  @Test public void onGlobalLayoutSubmitsRequestAndCleansUp() throws Exception {
+  @Test public void onGlobalLayoutSubmitsRequestAndCleansUp() {
     Picasso picasso = mock(Picasso.class);
     when(picasso.transformRequest(any(Request.class))).thenAnswer(TRANSFORM_REQUEST_ANSWER);