When rendering a set of version constraints to a string, we normalize
partially-constrained versions. This means converting a version
like 2.68.* to 2.68.0.
Prior to this commit, this normalization was done after deduplication.
This could result in a version constraints string with duplicate
entries, if multiple partially-constrained versions are equivalent. This
commit fixes this by normalizing before deduplicating and sorting.
An earlier commit made this remove duplicates, which set the precedent
that this function is trying to canonically represent the _meaning_ of
the version constraints rather than exactly how they were expressed in
the configuration.
Continuing in that vein, now we'll also apply a consistent (though perhaps
often rather arbitrary) ordering to the terms, so that it doesn't change
due to irrelevant details like declarations being written in a different
order in the configuration.
The ordering here is intended to be reasonably intuitive for simple cases,
but constraint strings with many different constraints are hard to
interpret no matter how we order them so the main goal is consistency,
so those watching how the constraints change over time (e.g. in logs of
Terraform output, or in the dependency log file) will see fewer noisy
changes that don't actually mean anything.
A set of version constraints can contain duplicates. This can happen if
multiple identical constraints are specified throughout a configuration.
When rendering the set, it is confusing to display redundant
constraints. This commit changes the string renderer to only show the
first instance of a given constraint, and adds unit tests for this
function to cover this change.
This also fixes a bug with the locks file generation: previously, a
configuration with redundant constraints would result in this error on
second init:
Error: Invalid provider version constraints
on .terraform.lock.hcl line 6:
(source code not available)
The recorded version constraints for provider
registry.terraform.io/hashicorp/random must be written in normalized form:
"3.0.0".
Alisdair McDiarmid