Store the async-await compiled pub code directly in the repo.

sdk/lib/_internal/pub_generated/test/snapshot/doesnt_snapshot_path_dependency_test.dart

+library pub_tests;
+import 'package:path/path.dart' as p;
+import 'package:scheduled_test/scheduled_test.dart';
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+main() {
+  initConfig();
+  integration("doesn't create a snapshot for a path dependency", () {
+    d.dir(
+        "foo",
+        [
+            d.libPubspec("foo", "1.2.3"),
+            d.dir(
+                "bin",
+                [
+                    d.dir(
+                        "bin",
+                        [d.file("hello.dart", "void main() => print('hello!');")])])]).create();
+    d.appDir({
+      "foo": {
+        "path": "../foo"
+      }
+    }).create();
+    pubGet();
+    d.nothing(p.join(appPath, '.pub', 'bin')).validate();
+  });
+}