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# Description
Fixes#14054
This PR fixes a problem that the engine cannot forward a cancellation
signal to the provider, because the plugin context is already closed. An
[earlier
commit](a9ae602867)
made the plugin context be closed too eagerly, with the intent of
cancelling plugin installation. This PR attempts to decouple the
cancellation of plugin installation from the lifecycle of the plugin
context, so that plugin installation may be cancelled during the
cancelation phase as opposed to the termination phase. Then, it closes
the plugin context in termination phase.
There's an existing test case in the engine lifecycle tests called
`TestProviderCancellation`, but it didn't catch the problem because it
uses a fake plugin host that behaves differently after being closed. The
issue was fixed in https://github.com/pulumi/pulumi/pull/14063 and the
test was temporarily disabled. This PR re-enables the test case.
A new test case `TestSourceFuncCancellation` is added to test
cancellation of the source func (where plugin installation happens, see
[update.go](https://github.com/pulumi/pulumi/pull/14057/files#diff-7d2ca3e83a05073b332435271496050e28466b4f7af8c0c91bbc77947a75a3a2R378)),
as this was the original motivation of
a9ae602867.
## Checklist
- [x] I have run `make tidy` to update any new dependencies
- [x] I have run `make lint` to verify my code passes the lint check
- [ ] I have formatted my code using `gofumpt`
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- [x] I have added tests that prove my fix is effective or that my
feature works
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- [x] I have run `make changelog` and committed the
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