feat(bazel/spec-bundling): generate ESM mjs bundle for node spec bundles

bazel/esbuild/index.bzl

@@ -19,6 +19,33 @@ def esbuild(
         **kwargs
     )
 
+def esbuild_esm_bundle(name, **kwargs):
+    """ESBuild macro supports an ESM/CJS interop.
+
+    Args:
+      name: Name of the target
+      **kwargs: Other arguments passed to the `esbuild` rule.
+    """
+
+    args = dict(
+        resolveExtensions = [".mjs", ".js"],
+        outExtension = {".js": ".mjs"},
+        # Workaround for: https://github.com/evanw/esbuild/issues/1921.
+        banner = {
+            "js": """
+import {createRequire as __cjsCompatRequire} from 'module';
+const require = __cjsCompatRequire(import.meta.url);
+""",
+        },
+    )
+
+    esbuild(
+        name = name,
+        format = "esm",
+        args = args,
+        **kwargs
+    )
+
 def esbuild_amd(name, entry_point, module_name, testonly = False, config = None, deps = [], **kwargs):
     """Generates an AMD bundle for the specified entry-point with the given AMD module name."""
     expand_template(
@@ -47,6 +74,7 @@ def esbuild_amd(name, entry_point, module_name, testonly = False, config = None,
         testonly = testonly,
         deps = deps,
         entry_point = entry_point,
+        format = "iife",
         config = "%s_config_lib" % name,
         **kwargs
     )

bazel/spec-bundling/esbuild.config-tmpl.mjs

@@ -29,8 +29,5 @@ export default {
   conditions: ['es2020', 'es2015', 'module'],
   // This ensures that we prioritize ES2020. RxJS would otherwise use the ESM5 output.
   mainFields: ['es2020', 'es2015', 'module', 'main'],
-  // Use the `iife` format for the test entry-point as tests should run immediately.
-  // For browser tests which are wrapped in an AMD header and footer, this works as well.
-  format: 'iife',
   plugins,
 };

bazel/spec-bundling/index.bzl

@@ -1,5 +1,5 @@
 load("@build_bazel_rules_nodejs//:index.bzl", "js_library")
-load("//bazel/esbuild:index.bzl", "esbuild", "esbuild_amd", "esbuild_config")
+load("//bazel/esbuild:index.bzl", "esbuild_amd", "esbuild_config", "esbuild_esm_bundle")
 load("//bazel/spec-bundling:spec-entrypoint.bzl", "spec_entrypoint")
 load("//bazel/spec-bundling:bundle-config.bzl", "spec_bundle_config_file")
 
@@ -63,16 +63,16 @@ def spec_bundle(
 
     # Browser tests (Karma) need named AMD modules to load.
     # TODO(devversion): consider updating `@bazel/concatjs` to support loading JS files directly.
-    esbuild_rule = esbuild_amd if is_browser_test else esbuild
+    esbuild_rule = esbuild_amd if is_browser_test else esbuild_esm_bundle
     amd_name = "%s/%s/%s" % (workspace_name, package_name, name + "_spec") if is_browser_test else None
 
     esbuild_rule(
         name = "%s_bundle" % name,
         testonly = True,
         config = ":%s_config" % name,
+        output = "%s_spec.%s" % (name, "js" if is_browser_test else "mjs"),
         entry_point = ":%s_spec_entrypoint" % name,
         module_name = amd_name,
-        output = "%s_spec.js" % name,
         target = target,
         platform = platform,
         deps = deps + [":%s_spec_entrypoint" % name],

ng-dev/utils/test/BUILD.bazel

@@ -14,5 +14,8 @@ ts_library(
 
 jasmine_node_test(
     name = "test",
+    data = ["@npm//@yarnpkg/lockfile"],
+    # Same reasoning as in "ng-dev/BUILD.bazel". This package cannot be bundled.
+    external = ["@yarnpkg/lockfile"],
     specs = [":test_lib"],
 )

tools/esbuild.bzl

@@ -1,10 +1,21 @@
-load("//bazel/esbuild:index.bzl", _esbuild = "esbuild", _esbuild_config = "esbuild_config")
+load(
+    "//bazel/esbuild:index.bzl",
+    _esbuild = "esbuild",
+    _esbuild_config = "esbuild_config",
+    _esbuild_esm_bundle = "esbuild_esm_bundle",
+)
 load("//bazel:extract_js_module_output.bzl", "extract_js_module_output")
 load("@build_bazel_rules_nodejs//:index.bzl", "generated_file_test")
 
 esbuild_config = _esbuild_config
 
-def esbuild(name, platform = "node", target = "node14", deps = [], **kwargs):
+def _esbuild_devmode_prioritize(
+        esbuild_rule,
+        name,
+        platform = "node",
+        target = "node14",
+        deps = [],
+        **kwargs):
     # TODO: Rename once devmode and prodmode have been combined.
     # This helps speeding up building as ESBuild (used internally by the rule) would
     # request both devmode and prodmode output flavor (resulting in 2x TS compilations).
@@ -19,39 +30,23 @@ def esbuild(name, platform = "node", target = "node14", deps = [], **kwargs):
         include_declarations = False,
     )
 
-    _esbuild(
+    esbuild_rule(
         name = name,
         platform = platform,
         target = target,
         deps = [":%s_devmode_deps" % name],
         **kwargs
     )
 
-def esbuild_esm_bundle(name, **kwargs):
-    """ESBuild macro that prioritizes ESM output and supports an ESM/CJS interop.
-
-    Args:
-      name: Name of the target
-      deps: List of dependencies
-      **kwargs: Other arguments passed to the `esbuild` rule.
-    """
-
-    args = dict(
-        resolveExtensions = [".mjs", ".js"],
-        outExtension = {".js": ".mjs"},
-        # Workaround for: https://github.com/evanw/esbuild/issues/1921.
-        banner = {
-            "js": """
-import {createRequire as __cjsCompatRequire} from 'module';
-const require = __cjsCompatRequire(import.meta.url);
-""",
-        },
+def esbuild(**kwargs):
+    _esbuild_devmode_prioritize(
+        _esbuild,
+        **kwargs
     )
 
-    esbuild(
-        name = name,
-        format = "esm",
-        args = args,
+def esbuild_esm_bundle(**kwargs):
+    _esbuild_devmode_prioritize(
+        _esbuild_esm_bundle,
         **kwargs
     )