I have a go_binary in Bazel called dbgen that generates Go files from SQL files. I want to create a new Bazel rule that wraps the dbgen binary to create the Go files in Bazel. However, I hit the following error when building with the new rule.

could not locate runfiles directory

How do I fix this error in the Bazel rule implementation below?

Details

The dbgen command that I want to wrap works if I invoke it with bazel run directly, meaning it can access the runfiles.

bazel run dbgen -- --pggen=./pggen --query-files foo.pggen.sql

Here's the rule I'm attempting to create. The error could not locate runfiles directory is a result calling the bazel.ListRunfiles Go library in rules_go. It seems that when Bazel executes the ctx.actions.run that the command doesn't get the runfiles of the tools dependencies.

rule.bzl

def _erp_pggen_impl(ctx):
    args = ctx.actions.args()
    args.add("--pggen", ctx.executable._pggen.path)
    args.add("--query-files", ",".join([s.path for s in ctx.files.srcs]))
    outs = [
        ctx.actions.declare_file(file.path.replace(".pggen.sql", ".pggen.sql.go"))
        for file in ctx.files.srcs
    ]
    ctx.actions.run(
        inputs = [ctx.executable._pggen] + ctx.files.srcs,
        outputs = outs,
        executable = ctx.attr._dbgen.files_to_run,
        tools = [ctx.executable._dbgen],
        arguments = [args],
        mnemonic = "ErpDbgen",
    )
    return [
        DefaultInfo(files = depset(outs)),
        OutputGroupInfo(go_generated_srcs = outs),
    ]

erp_pggen = rule(
    implementation = _erp_pggen_impl,
    attrs = {
        "srcs": attr.label_list(allow_files = [".pggen.sql"]),
        "_dbgen": attr.label(
            executable = True,
            cfg = "host",
            default = Label("//erp/db/dbgen:dbgen"),
        ),
        "_pggen": attr.label(
            executable = True,
            cfg = "host",
            default = Label("//third_party/go/pggen:pggen"),
        ),
    }
)

Related issues

• https://github.com/bazelbuild/bazel/issues/5463: issue setting the runfiles for the scala toolchain.

Bazel version: 4.2 OS: macOS