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.
This schema can be used to validate the contents of a Pulumi deployment.
If a deployment validates against this schema, it should be considered
syntactically valid, though it may contain certain classes of semantic
errors (e.g. references to unknown resources in dependency lists,
dependency cycles, etc.).
This schema is not yet used for validation in practice and may not be
entirely accurate.
These changes also add this schema (and the schemas on which it depends)
to the developer documentation. jsonschema2md.go has been updated to
support multi-file schemas.
The Pulumi Package metaschema is a JSON schema definition that describes
the format of a Pulumi Package schema. The metaschema can be used to
validate certain basic properties of a Pulumi Package schema, including
(but not limited to):
- data types (e.g. is this property a string?)
- data formats (e.g. is this string property a valid regex?)
- object shapes (e.g. is this object missing required properties?)
The schema binder has been updated to use the metaschema as its first
validation pass.
In addition to its use in the binder, the metaschema has its own page in
the developer documentation. This page is generated using a small tool,
jsonschema2md.go.