flutter test is taking almost the same amount of time on a second run as the first, when the app should already be built.
On iOS this causes every test run to take an additional ~15 seconds.

test is subverting flutter assemble caching logic by passing in a new temp directory target listener.dart path every run, even when running the same test. This causes the build system to create a new build directory from the hash of the inputs including TargetFile.

Every subsequent test run shows the assemble steps as needing a rerun due to InvalidatedReasonKind.inputChanged since each new build directory is missing the file store cache file from the last run:

            [  +31 ms] debug_unpack_ios: Starting due to {InvalidatedReasonKind.inputChanged: The following inputs have updated contents: /Users/m/Projects/flutter/packages/flutter_tools/lib/src/build_system/targets/ios.dart,/Users/magder/Projects/flutter/bin/internal/engine.version}
            [+1026 ms] Skipping target: gen_localizations
            [   +5 ms] gen_dart_plugin_registrant: Starting due to {InvalidatedReasonKind.inputChanged: The following inputs have updated contents: /Users/m/Projects/plugins/packages/google_maps_flutter/google_maps_flutter/example/.dart_tool/package_config_subset}
            [   +4 ms] debug_unpack_ios: Complete
...
            [   +6 ms] gen_dart_plugin_registrant: Complete

For example, in google_maps_flutter example project running the same command twice:

$ flutter --no-color test --machine --start-paused --plain-name testGetVisibleRegion  -v integration_test/google_maps_test.dart

calls identical assemble except for the different -dTargetFiles:

--verbose assemble --no-version-check --output=/Users/m/Projects/plugins/packages/google_maps_flutter/google_maps_flutter/example/build/ios/Debug-iphonesimulator/ -dTargetPlatform=ios -dTargetFile=/var/folders/bx/pyplw7v92lj58gm3_lztz5sc00mfq2/T/flutter_tools.5RYflD/flutter_test_listener.sO5mgy/listener.dart -dBuildMode=debug -dIosArchs=x86_64 -dSdkRoot=/Users/m/Applications/Xcode-14_beta3.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator16.0.sdk -dSplitDebugInfo= -dTreeShakeIcons=false -dTrackWidgetCreation=true -dDartObfuscation=false -dEnableBitcode= --ExtraGenSnapshotOptions= --DartDefines=RkxVVFRFUl9XRUJfQVVUT19ERVRFQ1Q9dHJ1ZQ==,SU5URUdSQVRJT05fVEVTVF9TSE9VTERfUkVQT1JUX1JFU1VMVFNfVE9fTkFUSVZFPWZhbHNl --ExtraFrontEndOptions= -dCodesignIdentity=- debug_ios_bundle_flutter_assets

--verbose assemble --no-version-check --output=/Users/m/Projects/plugins/packages/google_maps_flutter/google_maps_flutter/example/build/ios/Debug-iphonesimulator/ -dTargetPlatform=ios -dTargetFile=/var/folders/bx/pyplw7v92lj58gm3_lztz5sc00mfq2/T/flutter_tools.r0Vvcj/flutter_test_listener.uguobQ/listener.dart -dBuildMode=debug -dIosArchs=x86_64 -dSdkRoot=/Users/m/Applications/Xcode-14_beta3.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator16.0.sdk -dSplitDebugInfo= -dTreeShakeIcons=false -dTrackWidgetCreation=true -dDartObfuscation=false -dEnableBitcode= --ExtraGenSnapshotOptions= --DartDefines=RkxVVFRFUl9XRUJfQVVUT19ERVRFQ1Q9dHJ1ZQ==,SU5URUdSQVRJT05fVEVTVF9TSE9VTERfUkVQT1JUX1JFU1VMVFNfVE9fTkFUSVZFPWZhbHNl --ExtraFrontEndOptions= -dCodesignIdentity=- debug_ios_bundle_flutter_assets