feat(rollup): add args attribute to rollup_bundle rule (#1681)

Arguments passed to rollup. These can be used to override config file settings.

These argument are appended to the command line before all arguments that are always added by the
rule such as `--output.dir` or `--output.file`, `--format`, `--config` and `--preserveSymlinks` and
also those that are optionally added by the rule such as `--sourcemap`.

See rollup CLI docs https://rollupjs.org/guide/en/#command-line-flags for complete list of supported arguments.

Author: gregmagolan

packages/rollup/src/rollup_bundle.bzl

@@ -65,6 +65,16 @@ You must not repeat file(s) passed to entry_point/entry_points.
         # Don't try to constrain the filenames, could be json, svg, whatever
         allow_files = True,
     ),
+    "args": attr.string_list(
+        doc = """Command line arguments to pass to rollup. Can be used to override config file settings.
+
+These argument passed on the command line before all arguments that are always added by the
+rule such as `--output.dir` or `--output.file`, `--format`, `--config` and `--preserveSymlinks` and
+also those that are optionally added by the rule such as `--sourcemap`.
+
+See rollup CLI docs https://rollupjs.org/guide/en/#command-line-flags for complete list of supported arguments.""",
+        default = [],
+    ),
     "config_file": attr.label(
         doc = """A rollup.config.js file
 
@@ -286,6 +296,9 @@ def _rollup_bundle(ctx):
     # See CLI documentation at https://rollupjs.org/guide/en/#command-line-reference
     args = ctx.actions.args()
 
+    # Add user specified arguments *before* rule supplied arguments
+    args.add_all(ctx.attr.args)
+
     # List entry point argument first to save some argv space
     # Rollup doc says
     # When provided as the first options, it is equivalent to not prefix them with --input

packages/rollup/test/sourcemaps/BUILD.bazel

@@ -4,6 +4,11 @@ load("@npm_bazel_rollup//:index.from_src.bzl", "rollup_bundle")
 rollup_bundle(
     name = "bundle",
     srcs = ["s.js"],
+    # Test existance of args attribute
+    args = [
+        "--environment",
+        "FOO,BAR:baz",
+    ],
     # Use the desugared form to assert that it works
     entry_points = {"input.js": "bundle"},
     sourcemap = "true",