build: add an npm_package rule for @angular/bazel (#22628)

PR Close #22628

packages/bazel/BUILD.bazel

@@ -1 +1,23 @@
-# Empty marker file, indicating this directory is a Bazel package.
+load("@build_bazel_rules_nodejs//:defs.bzl", "npm_package")
+
+genrule(
+    name = "workspace",
+    outs = ["WORKSPACE"],
+    cmd = "echo 'workspace(name=\"angular\")' > $@",
+)
+
+npm_package(
+    name = "npm_package",
+    srcs = [
+        "package.json",
+        "index.bzl",
+        "//packages/bazel/src:package_assets",
+    ],
+    deps = [":workspace"],
+    # Re-host //packages/bazel/ which is just // in the public distro
+    replacements = {
+        "//packages/bazel/": "//",
+        "angular/packages/bazel/": "angular/",
+    },
+    stamp_data = "//tools:stamp_data",
+)

packages/bazel/src/BUILD.bazel

@@ -1,5 +1,14 @@
 package(default_visibility = ["//visibility:public"])
 
+filegroup(
+    name = "package_assets",
+    srcs = glob(["*"]) + [
+        "//packages/bazel/src/ng_package:package_assets",
+        "//packages/bazel/src/ngc-wrapped:package_assets",
+    ],
+    visibility = ["//packages/bazel:__subpackages__"],
+)
+
 load("@build_bazel_rules_nodejs//:defs.bzl", "nodejs_binary")
 
 nodejs_binary(

packages/bazel/src/ng_package/BUILD.bazel

@@ -1,5 +1,11 @@
 package(default_visibility = ["//visibility:public"])
 
+filegroup(
+    name = "package_assets",
+    srcs = glob(["*"]),
+    visibility = ["//packages/bazel:__subpackages__"],
+)
+
 load("@build_bazel_rules_nodejs//:defs.bzl", "nodejs_binary")
 load("@build_bazel_rules_typescript//:defs.bzl", "ts_library")
 

packages/bazel/src/ngc-wrapped/BUILD.bazel

@@ -1,6 +1,12 @@
 load("@build_bazel_rules_nodejs//:defs.bzl", "nodejs_binary")
 load("@build_bazel_rules_typescript//:defs.bzl", "ts_library")
 
+filegroup(
+    name = "package_assets",
+    srcs = glob(["*"]),
+    visibility = ["//packages/bazel:__subpackages__"],
+)
+
 ts_library(
     name = "ngc_lib",
     srcs = [