Fixes https://github.com/pulumi/pulumi/issues/12738https://github.com/pulumi/pulumi/pull/11834 turned on the prealloc
linter and changed a load of slice uses from just `var x T[]` to `x :=
make([]T, 0, preallocSize)`. This was good for performance but it turns
out there are a number of places in the codebase that treat a `nil`
slice as semnatically different to an empty slice.
Trying to test that, or even reason that through for every callsite is
untractable, so this PR replaces all expressions of the form `make([]T,
0, size)` with a call to `slice.Prealloc[T](size)`. When size is 0 that
returns a nil array, rather than an empty array.
Per team discussion, switching to gofumpt.
[gofumpt][1] is an alternative, stricter alternative to gofmt.
It addresses other stylistic concerns that gofmt doesn't yet cover.
[1]: https://github.com/mvdan/gofumpt
See the full list of [Added rules][2], but it includes:
- Dropping empty lines around function bodies
- Dropping unnecessary variable grouping when there's only one variable
- Ensuring an empty line between multi-line functions
- simplification (`-s` in gofmt) is always enabled
- Ensuring multi-line function signatures end with
`) {` on a separate line.
[2]: https://github.com/mvdan/gofumpt#Added-rules
gofumpt is stricter, but there's no lock-in.
All gofumpt output is valid gofmt output,
so if we decide we don't like it, it's easy to switch back
without any code changes.
gofumpt support is built into the tooling we use for development
so this won't change development workflows.
- golangci-lint includes a gofumpt check (enabled in this PR)
- gopls, the LSP for Go, includes a gofumpt option
(see [installation instrutions][3])
[3]: https://github.com/mvdan/gofumpt#installation
This change was generated by running:
```bash
gofumpt -w $(rg --files -g '*.go' | rg -v testdata | rg -v compilation_error)
```
The following files were manually tweaked afterwards:
- pkg/cmd/pulumi/stack_change_secrets_provider.go:
one of the lines overflowed and had comments in an inconvenient place
- pkg/cmd/pulumi/destroy.go:
`var x T = y` where `T` wasn't necessary
- pkg/cmd/pulumi/policy_new.go:
long line because of error message
- pkg/backend/snapshot_test.go:
long line trying to assign three variables in the same assignment
I have included mention of gofumpt in the CONTRIBUTING.md.
Removes unnecessary appends in pkg.
There were two instances:
- append into a slice that's never used again
- append with nothing to append (`append([]{foo}) == []{foo}`)
Issue found by staticcheck:
```
testing/integration/program.go:2190:15: SA4021: x = append(y) is equivalent to x = y (staticcheck)
testing/integration/program.go:2192:15: SA4021: x = append(y) is equivalent to x = y (staticcheck)
codegen/pcl/utilities.go:158:11: SA4010: this result of append is never used, except maybe in other appends (staticcheck)
```
Refs #11808