Merge branch 'flaky-test-addtimeviewmodeltest-droid-2101'

1 files changed, 6 insertions, 0 deletions

diff --git a/android/lib/common-test/src/main/java/net/mullvad/mullvadvpn/lib/common/test/TestCoroutineRule.kt b/android/lib/common-test/src/main/java/net/mullvad/mullvadvpn/lib/common/test/TestCoroutineRule.kt
index 34d6739119..c73516f72d 100644
--- a/android/lib/common-test/src/main/java/net/mullvad/mullvadvpn/lib/common/test/TestCoroutineRule.kt
+++ b/android/lib/common-test/src/main/java/net/mullvad/mullvadvpn/lib/common/test/TestCoroutineRule.kt
@@ -10,6 +10,12 @@ import org.junit.jupiter.api.extension.AfterEachCallback
 import org.junit.jupiter.api.extension.BeforeEachCallback
 import org.junit.jupiter.api.extension.ExtensionContext
 
+/**
+ * Should be applied to any test class that has a test subject that uses the main dispatcher. This
+ * is the default dispatcher for coroutines on Android and is for example used by the
+ * viewModelScope. This avoids test flakiness due to the test dispatcher eagerly starting coroutines
+ * instead of waiting for runCurrent for them to start.
+ */
 @OptIn(ExperimentalCoroutinesApi::class)
 class TestCoroutineRule(val testDispatcher: TestDispatcher = UnconfinedTestDispatcher()) :
     BeforeEachCallback, AfterEachCallback {