Fix isDisplayingAtLeast() matcher to factor in the scale of ancestor views.

espresso/CHANGELOG.md

@@ -20,6 +20,7 @@ The following artifacts were released:
 * Don't suppress AppNotIdleException if dumpThreadStates throws.
 * Remove Espresso.onIdle tracing
 * Fix NullPointerException in UiControllerImpl.
+* Fix `isDisplayingAtLeast` matcher to factor in the scale of ancestor views.
 
 **New Features**
 

espresso/core/java/androidx/test/espresso/matcher/ViewMatchers.java

@@ -994,16 +994,23 @@ protected boolean matchesSafely(View view, Description mismatchDescription) {
 
       Rect screen = getScreenWithoutStatusBarActionBar(view);
 
-      float viewHeight = (view.getHeight() > screen.height()) ? screen.height() : view.getHeight();
-      float viewWidth = (view.getWidth() > screen.width()) ? screen.width() : view.getWidth();
+      float totalScaleX = view.getScaleX();
+      float totalScaleY = view.getScaleY();
+      ViewParent parent = view.getParent();
+      while (parent instanceof View) {
+        View parentView = (View) parent;
+        totalScaleX *= parentView.getScaleX();
+        totalScaleY *= parentView.getScaleY();
+        parent = parentView.getParent();
+      }
 
-      // factor in the View's scaleX and scaleY properties.
-      viewHeight = Math.min(view.getHeight() * Math.abs(view.getScaleY()), screen.height());
-      viewWidth = Math.min(view.getWidth() * Math.abs(view.getScaleX()), screen.width());
+      // factor in the View and its ancestors' scaleX and scaleY properties.
+      float viewHeight = Math.min(view.getHeight() * Math.abs(totalScaleY), screen.height());
+      float viewWidth = Math.min(view.getWidth() * Math.abs(totalScaleX), screen.width());
 
       double maxArea = viewHeight * viewWidth;
       double visibleArea = visibleParts.height() * visibleParts.width();
-      int displayedPercentage = (int) ((visibleArea / maxArea) * 100);
+      int displayedPercentage = maxArea > 0 ? (int) ((visibleArea / maxArea) * 100) : 0;
 
       if (displayedPercentage < areaPercentage) {
         mismatchDescription

espresso/core/javatests/androidx/test/espresso/matcher/ViewMatchers1Test.java

@@ -65,6 +65,7 @@
 import android.widget.CheckBox;
 import android.widget.Checkable;
 import android.widget.CheckedTextView;
+import android.widget.FrameLayout;
 import android.widget.LinearLayout;
 import android.widget.RadioButton;
 import android.widget.RelativeLayout;
@@ -767,6 +768,32 @@ public void isDisplayingAtLeastTest() {
     assertTrue(isDisplayingAtLeast(20).matches(view));
   }
 
+  @Test
+  public void isDisplayingAtLeast_withParentScale() {
+    GlobalVisibleRectProvider providerMock = mock(GlobalVisibleRectProvider.class);
+    FrameLayout parent = new FrameLayout(context);
+    View child = new GlobalVisibleRectTestView(context, providerMock);
+    parent.addView(child);
+
+    // Set the view to be 100x100 with scale(0.5, -0.5): 2,500 pixels
+    child.setVisibility(View.VISIBLE);
+    child.layout(0, 0, 100, 100);
+    child.setScaleX(0.5f);
+    parent.setScaleY(-0.5f);
+    when(providerMock.get(any(), any()))
+        .then(
+            (Answer<Boolean>)
+                invocation -> {
+                  // Set the output rectangle to 40x40: 1,600 pixels
+                  Rect argRect = invocation.getArgument(0);
+                  argRect.set(0, 0, 40, 40);
+                  return true;
+                });
+
+    assertFalse(isDisplayingAtLeast(70).matches(child));
+    assertTrue(isDisplayingAtLeast(60).matches(child));
+  }
+
   @Test
   public void isDisplayingAtLeast_description() {
     assertThat(