From 6c2d53de6eb95458c9698c08ada2e29ece75f005 Mon Sep 17 00:00:00 2001
From: Brett Chabot <brettchabot@google.com>
Date: Mon, 17 Nov 2025 10:06:33 -0800
Subject: [PATCH] Remove tracing from `Espresso.onIdle`.

Espresso.onIdle can be called many times through the life of a test,
creating memory issues for long running tests and providing questionable
value.

With this commit, the `Espresso.onIdle` method no longer creates a tracing span. Corresponding tests for the span are also removed.

PiperOrigin-RevId: 833388360
---
 espresso/CHANGELOG.md                         |  1 +
 .../java/androidx/test/espresso/Espresso.java | 60 +++++++++----------
 .../androidx/test/espresso/EspressoTest.java  |  6 --
 3 files changed, 30 insertions(+), 37 deletions(-)

diff --git a/espresso/CHANGELOG.md b/espresso/CHANGELOG.md
index 3763cf58b..89a4f06b1 100644
--- a/espresso/CHANGELOG.md
+++ b/espresso/CHANGELOG.md
@@ -18,6 +18,7 @@ The following artifacts were released:
 
 * Replace now-unnecessary reflection from TestLooperManagerCompat when using Android SDK 36 APIs
 * Don't suppress AppNotIdleException if dumpThreadStates throws.
+* Remove Espresso.onIdle tracing
 
 **New Features**
 
diff --git a/espresso/core/java/androidx/test/espresso/Espresso.java b/espresso/core/java/androidx/test/espresso/Espresso.java
index 83f2b03c9..3eadd0efb 100644
--- a/espresso/core/java/androidx/test/espresso/Espresso.java
+++ b/espresso/core/java/androidx/test/espresso/Espresso.java
@@ -323,39 +323,37 @@ private static void waitUntilNextFrame(int times) {
    * @throws AppNotIdleException when app does not go Idle within the master policies timeout.
    */
   public static <T> T onIdle(Callable<T> action) {
-    try (Span ignored = tracer.beginSpan("Espresso.onIdle")) {
-      if (Thread.currentThread().equals(Looper.getMainLooper().getThread())) {
-        BASE.controlledLooper().drainMainThreadUntilIdle();
-        BASE.uiController().loopMainThreadUntilIdle();
-        try {
-          return action.call();
-        } catch (Exception e) {
-          throw new RuntimeException("Callable action in onIdle reported an exception.", e);
-        }
-      }
-      FutureTask<T> actionTask = new FutureTask<>(action);
-      ListenableFutureTask<Void> idleFuture =
-          ListenableFutureTask.create(
-              () -> {
-                BASE.uiController().loopMainThreadUntilIdle();
-                return null;
-              });
-      Executor mainThreadExecutor = BASE.mainThreadExecutor();
-      idleFuture.addListener(actionTask, mainThreadExecutor);
-      mainThreadExecutor.execute(idleFuture);
+    if (Thread.currentThread().equals(Looper.getMainLooper().getThread())) {
       BASE.controlledLooper().drainMainThreadUntilIdle();
-
+      BASE.uiController().loopMainThreadUntilIdle();
       try {
-        idleFuture.get();
-        return actionTask.get();
-      } catch (InterruptedException ie) {
-        throw new RuntimeException(ie);
-      } catch (ExecutionException ee) {
-        if (ee.getCause() instanceof AppNotIdleException) {
-          throw (AppNotIdleException) ee.getCause();
-        } else {
-          throw new RuntimeException(ee);
-        }
+        return action.call();
+      } catch (Exception e) {
+        throw new RuntimeException("Callable action in onIdle reported an exception.", e);
+      }
+    }
+    FutureTask<T> actionTask = new FutureTask<>(action);
+    ListenableFutureTask<Void> idleFuture =
+        ListenableFutureTask.create(
+            () -> {
+              BASE.uiController().loopMainThreadUntilIdle();
+              return null;
+            });
+    Executor mainThreadExecutor = BASE.mainThreadExecutor();
+    idleFuture.addListener(actionTask, mainThreadExecutor);
+    mainThreadExecutor.execute(idleFuture);
+    BASE.controlledLooper().drainMainThreadUntilIdle();
+
+    try {
+      idleFuture.get();
+      return actionTask.get();
+    } catch (InterruptedException ie) {
+      throw new RuntimeException(ie);
+    } catch (ExecutionException ee) {
+      if (ee.getCause() instanceof AppNotIdleException) {
+        throw (AppNotIdleException) ee.getCause();
+      } else {
+        throw new RuntimeException(ee);
       }
     }
   }
diff --git a/espresso/core/javatests/androidx/test/espresso/EspressoTest.java b/espresso/core/javatests/androidx/test/espresso/EspressoTest.java
index 58e293dfc..1ef054b3b 100644
--- a/espresso/core/javatests/androidx/test/espresso/EspressoTest.java
+++ b/espresso/core/javatests/androidx/test/espresso/EspressoTest.java
@@ -428,9 +428,6 @@ public void onData_throwsFromScenarioOnActivity() {
   @Test
   public void onIdle_worksFromScenarioOnActivity() {
     rule.getScenario().onActivity(activity -> onIdle());
-
-    assertThat(
-        tracer.getSpans(), contains("beginSpan: Espresso.onIdle", "+-endSpan: Espresso.onIdle"));
   }
 
   @Test
@@ -445,9 +442,6 @@ public void onIdle_worksFromMainThread() throws Exception {
         });
 
     latch.await();
-
-    assertThat(
-        tracer.getSpans(), contains("beginSpan: Espresso.onIdle", "+-endSpan: Espresso.onIdle"));
   }
 
   private static class DummyIdlingResource implements IdlingResource {