go-jsonnet fails as a dependency in bzlmod using Gazelle

[antholeole]

x-post from stackoverflow

I've put together an MVP for a build failure relating to gazelle and com_github_google_go_jsonnet: https://github.com/antholeole/bug-repro/tree/bazel

in short, I have a BUILD.bazel that looks like this:

go_library(
    name = "src_lib",
    srcs = ["main.go"],
    importpath = "repro/src",
    visibility = ["//visibility:private"],
    deps = ["@com_github_google_go_jsonnet//:go-jsonnet"],
)

building the target (in the repro, //src:src) gives the following output:

no such package '@@[unk
nown repo 'cpp_jsonnet' requested from @@gazelle++go_deps+com_github_google_go_jsonnet]//stdlib': The repository '@@[unknown repo 'cpp_jsonnet' requested from @@gazelle++go_deps+com_
github_google_go_jsonnet]' could not be resolved: No repository visible as '@cpp_jsonnet' from repository '@@gazelle++go_deps+com_github_google_go_jsonnet' and referenced by '@@gazel
le++go_deps+com_github_google_go_jsonnet//astgen:dumpstdlibast'

is there any way to supply the dependency with @cpp_jsonnet? I've tried to add a module that looks like that to the MODULE.bazel (the error changed but did not go away completely), but it smells like an antipattern. Hopefully there's an easier way to get jsonnet with gazelle.

[linhua11]

is there any fix to this?

[linhua11]

@antholeole

For anyone having the similiar issue, fixed it by
#keep
go_repository(
name = "com_github_google_go_jsonnet",
importpath = "github.com/google/go-jsonnet",
repo_mapping = {"@cpp_jsonnet": "@com_github_google_jsonnet"},
sum = "h1:WG4TTSARuV7bSm4PMB4ohjxe33IHT5WVTrJSU33uT4g=",
version = "v0.20.0",
)

#keep
go_repository(
name = "com_github_google_jsonnet",
importpath = "github.com/google/jsonnet",
sum = "h1:JZkvqvtuPRJ3l6aqlhMAHeYR3SOzaD8VpCR5GVpaR/0=",
version = "v0.20.0",
)

[antholeole]

@linhua11 thanks! I haven't tried this yet. once i do I'll close if it works.

[zaka634]

@linhua11 , where do you put the fix into ? MODULE.bazel ?

[dbanetto]

For those coming across this, the above go_repository example will not work for bzlmod as the repo_mapping attribute is not supported with bzlmod.

However, bazel-contrib/bazel-gazelle#1802 solves the underlying problem here that go-jsonnet already has existing BUILD.bazel files. The existing BUILD.bazel files the rules for keeping the source code in sync cpp_jsonnet can be removed safely cleaned up.

A minimal example is:

# In a MODULE.bazel file
go_deps = use_extension("@gazelle//:extensions.bzl", "go_deps")

# ... usual prelude ... #

go_deps.gazelle_override(
    build_file_generation = "clean",
    path = "github.com/google/go-jsonnet",
)

go_deps.from_file(go_mod = "//:go.mod")
use_repo(
    go_deps,
    # ... rest of your go.mod deps
)

[aran]

@dbanetto this is a helpful tip, thank you. We were using a patch but this is better.