feat: bun_script

internal/BUILD.bazel

@@ -7,6 +7,7 @@ exports_files([
     "bun_bundle.bzl",
     "bun_dev.bzl",
     "bun_install.bzl",
+    "bun_script.bzl",
     "bun_test.bzl",
     "js_library.bzl",
 ])
@@ -27,6 +28,11 @@ bzl_library(
     srcs = ["bun_dev.bzl"],
 )
 
+bzl_library(
+    name = "bun_script_bzl",
+    srcs = ["bun_script.bzl"],
+)
+
 bzl_library(
     name = "bun_test_bzl",
     srcs = ["bun_test.bzl"],

internal/bun_install.bzl

@@ -19,7 +19,6 @@ def _select_bun_binary(repository_ctx):
 
     fail("Unsupported host platform: os={}, arch={}".format(repository_ctx.os.name, repository_ctx.os.arch))
 
-
 def _bun_install_repository_impl(repository_ctx):
     package_json = repository_ctx.path(repository_ctx.attr.package_json)
     bun_lockfile = repository_ctx.path(repository_ctx.attr.bun_lockfile)
@@ -60,7 +59,6 @@ stderr:
 """,
     )
 
-
 bun_install_repository = repository_rule(
     implementation = _bun_install_repository_impl,
     attrs = {
@@ -74,9 +72,6 @@ bun_install_repository = repository_rule(
     },
 )
 
-_bun_install_repository = bun_install_repository
-
-
 def bun_install(name, package_json, bun_lockfile):
     """Create an external repository containing installed node_modules.
 

internal/bun_script.bzl

@@ -0,0 +1,91 @@
+"""Rule for running package.json scripts with Bun."""
+
+
+def _shell_quote(value):
+    return "'" + value.replace("'", "'\"'\"'") + "'"
+
+
+def _bun_script_impl(ctx):
+    toolchain = ctx.toolchains["//bun:toolchain_type"]
+    bun_bin = toolchain.bun.bun_bin
+    package_json = ctx.file.package_json
+
+    launcher = ctx.actions.declare_file(ctx.label.name)
+    ctx.actions.write(
+        output = launcher,
+        is_executable = True,
+        content = """#!/usr/bin/env bash
+set -euo pipefail
+
+runfiles_dir="${{RUNFILES_DIR:-$0.runfiles}}"
+workspace_root="${{runfiles_dir}}/_main"
+bun_bin="${{runfiles_dir}}/_main/{bun_short_path}"
+package_json="${{runfiles_dir}}/_main/{package_json_short_path}"
+package_dir="$(dirname "${{package_json}}")"
+
+working_dir="{working_dir}"
+if [[ "${{working_dir}}" == "package" ]]; then
+    cd "${{package_dir}}"
+else
+    cd "${{workspace_root}}"
+fi
+
+exec "${{bun_bin}}" --bun run {script} "$@"
+""".format(
+            bun_short_path = bun_bin.short_path,
+            package_json_short_path = package_json.short_path,
+            working_dir = ctx.attr.working_dir,
+            script = _shell_quote(ctx.attr.script),
+        ),
+    )
+
+    transitive_files = []
+    if ctx.attr.node_modules:
+        transitive_files.append(ctx.attr.node_modules[DefaultInfo].files)
+
+    runfiles = ctx.runfiles(
+        files = [bun_bin, package_json] + ctx.files.data,
+        transitive_files = depset(transitive = transitive_files),
+    )
+
+    return [
+        DefaultInfo(
+            executable = launcher,
+            runfiles = runfiles,
+        ),
+    ]
+
+
+bun_script = rule(
+    implementation = _bun_script_impl,
+    doc = """Runs a named `package.json` script with Bun as an executable target.
+
+Use this rule to expose existing package scripts such as `dev`, `build`, or
+`check` via `bazel run` without adding wrapper shell scripts.
+""",
+    attrs = {
+        "script": attr.string(
+            mandatory = True,
+            doc = "Name of the `package.json` script to execute via `bun run <script>`.",
+        ),
+        "package_json": attr.label(
+            mandatory = True,
+            allow_single_file = True,
+            doc = "Label of the `package.json` file containing the named script.",
+        ),
+        "node_modules": attr.label(
+            doc = "Optional label providing Bun/npm package files in runfiles.",
+        ),
+        "data": attr.label_list(
+            allow_files = True,
+            doc = "Additional runtime files required by the script.",
+        ),
+        "working_dir": attr.string(
+            default = "package",
+            values = ["workspace", "package"],
+            doc = "Working directory at runtime: Bazel runfiles `workspace` root or the directory containing `package.json`.",
+        ),
+    },
+    executable = True,
+    toolchains = ["//bun:toolchain_type"],
+)

internal/js_library.bzl

@@ -1,7 +1,9 @@
 """Lightweight JS/TS source grouping rules."""
 
-BunSourcesInfo = provider(fields = ["transitive_sources"])
-
+BunSourcesInfo = provider(
+    "Provides transitive sources for Bun libraries.",
+    fields = ["transitive_sources"],
+)
 
 def _bun_library_impl(ctx):
     transitive_sources = [
@@ -18,7 +20,6 @@ def _bun_library_impl(ctx):
         DefaultInfo(files = all_sources),
     ]
 
-
 js_library = rule(
     implementation = _bun_library_impl,
     doc = "Aggregates JavaScript sources and transitive Bun source dependencies.",