Fix crash in SplashScreenManagerTests

cbracken · cbracken · commit 71cf91005b39 · 2026-04-24T09:16:53.000+09:00
Tests passed locally but
testLoadDefaultSplashScreenViewFailsWhenStoryboardNotFound crashed in
*some* CI runs with:

```
Test Case '-[ios_test_flutter_swift.SplashScreenManagerTests testLoadDefaultSplashScreenViewFailsWhenStoryboardNotFound]' started.
IosUnitTests(19638,0x10b879200) malloc: enabling scribbling to detect mods to free blocks
IosUnitTests(19638) MallocStackLogging: could not tag MSL-related memory as no_footprint, so those pages will be included in process footprint - (null)
IosUnitTests(19638) MallocStackLogging: recording malloc (and VM allocation) stacks using lite mode
2026-04-23 08:57:59.075045-0700 IosUnitTests[19638:136527] [General] Failed to send CA Event for app launch measurements for ca_event_type: 0 event_name: com.apple.app_launch_measurement.FirstFramePresentationMetric
2026-04-23 08:57:59.145240-0700 IosUnitTests[19638:136528] [General] Failed to send CA Event for app launch measurements for ca_event_type: 1 event_name: com.apple.app_launch_measurement.ExtendedLaunchMetrics
```

MockBundle subclassed Bundle, but relied on the default initializer.
Bundle is a class cluster and the default initializer really wants a
real bundle with a physical directory on disk. The mock overrides the
infoDictionary and path(forResource:ofType:) methods, but any other
methods will be on some uninitialised garbage version of Bundle.

To work around this, I bootstrapped it with the bundle for the tests
themselves. We still mock out the two methods we care about for the
test, but this should avoid the crash.
diff --git a/engine/src/flutter/shell/platform/darwin/ios/framework/Source/SplashScreenManagerTests.swift b/engine/src/flutter/shell/platform/darwin/ios/framework/Source/SplashScreenManagerTests.swift
@@ -14,6 +14,12 @@ final class MockBundle: Bundle {
   var mockInfoDictionary: [String: Any]?
   var mockPaths: [String: String] = [:]
 
+  override init() {
+    // Use the path of the test bundle to ensure valid internal state
+    let testBundle = Bundle(for: MockBundle.self)
+    super.init(path: testBundle.bundlePath)!
+  }
+
   override var infoDictionary: [String: Any]? {
     return mockInfoDictionary
   }
