The issue is related to this code:
https://github.com/pulumi/pulumi/blob/v0.16.4/pkg/workspace/plugins.go#L155-L195
Note that we use `defer` to ensure we close our handle to the file we
are unpacking when we encounter a file in the tarball. However, the
defers don't run until the containing function ends, so when we go to
do the rename, or process still has a bunch of open file handles, which
prevents the directory from being renamed because it is "in use".
By doing all of the work in an anonymous function, we ensure that the
defer statements run before we go to rename the directory
Fixes#2217
In the Pulumi Cloud, there is no guarantee that two stacks will share
the same encryption key. This means that encrypted config can not be
shared across stacks (in the Pulumi.yaml) file. To mimic this behavior
in the local experience, we now use a unique key per stack.
When upgrading an existing project, for any stack with existing
secrets, we copy the existing key into this stack. Future stacks will
get thier own encryption key. This strikes a balance between
expediency of implementation, the end user UX and not having to make a
breaking change.
As part of this change, I have introduced a CHANGELOG.md file in the
root of the repository and added a small note about the change to it.
Fixes#769
