Chris Bracken c947cfce7e [macOS] Clean up resources in ViewController tests (flutter/engine#47792)
Wraps all FlutterViewController tests in an autorelease pool to ensure
resources are cleaned up.

Adds a MockFlutterEngineTest subclass of AutoreleasePoolTest that
creates an OCPartialMock FlutterEngine and shuts it down at the end of
the test. Previously we were not shutting down any FlutterEngine
instances we allocated, resulting in potentially thousands of threads
and graphics contexts being allocated.

Prior to this change, running these tests via:

    ../out/host_debug_unopt_arm64/flutter_desktop_darwin_unittests \
        --gtest_filter='FlutterViewController.*' --gtest_repeat=1000

resulted in test failures and sometimes segfaults. This ensures
resources are cleaned up

Eventually all unit tests should configure their FlutterEngine via
either FlutterEngineTest (which should be an AutoreleasePoolTest) or
MockFlutterEngineTest, and the CreateMockFlutterEngine function moved to
a static used in the implementation of these.

Issue: https://github.com/flutter/flutter/issues/104789
Issue: https://github.com/flutter/flutter/issues/127441
Issue: https://github.com/flutter/flutter/issues/124840

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- [x] I read and followed the [Flutter Style Guide] and the [C++,
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- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I added new tests to check the change I am making or feature I am
adding, or the PR is [test-exempt]. See [testing the engine] for
instructions on writing and running engine tests.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I signed the [CLA].
- [x] All existing and new tests are passing.

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2023-11-07 23:50:31 -08:00
..

Flutter Engine

OpenSSF Scorecard SLSA 1

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