The ability to pin versions is handy when having to deal to packages that
bootstrap themselves through a chain of former versions. Not using pinned
versions in these case could introduce dependency cycles.
* guix/build-system/go.scm (guix)
(%go-version-rx): Rename to...
(%go-pseudo-version-rx): ... this. Simplify the regular expression, which in
turns makes it more robust.
* guix/build-system/go.scm (go-version->git-ref): Adjust following the above
rename.
(go-pseudo-version?): New predicate.
(go-module-latest-version): Rename to ...
(go-module-version-string): ... this. Rename goproxy-url argument to just
goproxy. Add a VERSION keyword argument, update docstring and adjust to have
it used.
(go-module-available-versions): New procedure.
(%go.mod-require-directive-rx): Document regexp.
(parse-go.mod): Harmonize the way dependencies are recorded to a list of lists
rather than a list of pairs, as done for other importers. Rewrite to directly pass
multiple values rather than a record object. Filter the replaced modules in a
functional style.
(go-module->guix-package): Add docstring.
[version, pin-versions?]: New arguments. Rename the GOPROXY-URL argument to
GOPROXY. Adjust to the new returned value of fetch-go.mod, which is a string.
Fail when the provided version doesn't exist. Return a list dependencies and
their versions when in pinned versions mode, else just the dependencies.
(go-module-recursive-import)[version, pin-versions?]: New arguments.
Honor the new arguments and guard against network errors.
* guix/scripts/import/go.scm (%default-options): Register a default value for
the goproxy argument.
(show-help): Document that a version can be specified. Remove the --version
argument and add a --pin-versions argument.
(%options)[version]: Remove option.
[pin-versions]: Add option.
(guix-import-go): Adjust so the version provided from the module name is
honored, along the new pin-versions? argument.
* tests/go.scm: Adjust and add new tests.