diff --git a/lib/src/barback/asset_environment.dart b/lib/src/barback/asset_environment.dart
index c07d8600244d3ae048ae7aa933d5e6ceea805b75..e3c8d26d9b590f8338d912d17e7567da1b4a803d 100644
--- a/lib/src/barback/asset_environment.dart
+++ b/lib/src/barback/asset_environment.dart
@@ -60,15 +60,19 @@ class AssetEnvironment {
/// entrypoints are loaded. Each entrypoint is expected to refer to a Dart
/// library.
///
+ /// If [environmentConstants] is passed, the constants it defines are passed
+ /// on to the built-in dart2js transformer.
+ ///
/// Returns a [Future] that completes to the environment once the inputs,
/// transformers, and server are loaded and ready.
static Future<AssetEnvironment> create(Entrypoint entrypoint,
BarbackMode mode, {WatcherType watcherType, String hostname, int basePort,
Iterable<String> packages, Iterable<AssetId> entrypoints,
- bool useDart2JS: true}) {
+ Map<String, String> environmentConstants, bool useDart2JS: true}) {
if (watcherType == null) watcherType = WatcherType.NONE;
if (hostname == null) hostname = "localhost";
if (basePort == null) basePort = 0;
+ if (environmentConstants == null) environmentConstants = {};
return log.progress("Loading asset environment", () async {
var graph = await entrypoint.loadPackageGraph();
@@ -77,7 +81,7 @@ class AssetEnvironment {
barback.log.listen(_log);
var environment = new AssetEnvironment._(graph, barback, mode,
- watcherType, hostname, basePort);
+ watcherType, hostname, basePort, environmentConstants);
await environment._load(entrypoints: entrypoints, useDart2JS: useDart2JS);
return environment;
@@ -125,6 +129,9 @@ class AssetEnvironment {
/// The mode to run the transformers in.
final BarbackMode mode;
+ /// Constants to passed to the built-in dart2js transformer.
+ final Map<String, String> environmentConstants;
+
/// The [Transformer]s that should be appended by default to the root
/// package's transformer cascade. Will be empty if there are none.
final _builtInTransformers = <Transformer>[];
@@ -158,7 +165,8 @@ class AssetEnvironment {
Set<AssetId> _modifiedSources;
AssetEnvironment._(this.graph, this.barback, this.mode,
- this._watcherType, this._hostname, this._basePort);
+ this._watcherType, this._hostname, this._basePort,
+ this.environmentConstants);
/// Gets the built-in [Transformer]s that should be added to [package].
///
diff --git a/lib/src/barback/dart2js_transformer.dart b/lib/src/barback/dart2js_transformer.dart
index 8c7ff14c0ebc63467759ac3ca87c8bc4f7dbe34a..9097e0747d2d38c37826e1478e9091d0f47fe76a 100644
--- a/lib/src/barback/dart2js_transformer.dart
+++ b/lib/src/barback/dart2js_transformer.dart
@@ -166,13 +166,15 @@ class Dart2JSTransformer extends Transformer implements LazyTransformer {
/// Parses and returns the "environment" configuration option.
Map<String, String> get _configEnvironment {
- if (!_settings.configuration.containsKey('environment')) return null;
+ if (!_settings.configuration.containsKey('environment')) {
+ return _environment.environmentConstants;
+ }
var environment = _settings.configuration['environment'];
if (environment is Map &&
environment.keys.every((key) => key is String) &&
environment.values.every((key) => key is String)) {
- return environment;
+ return mergeMaps(environment, _environment.environmentConstants);
}
throw new FormatException('Invalid value for \$dart2js.environment: '
diff --git a/lib/src/command/build.dart b/lib/src/command/build.dart
index 1a88922c2fc695bd85274821596ada401681426a..b07cd95d617b7c054fd607f49dba7d198cf5dc3c 100644
--- a/lib/src/command/build.dart
+++ b/lib/src/command/build.dart
@@ -35,6 +35,10 @@ class BuildCommand extends BarbackCommand {
int builtFiles = 0;
BuildCommand() {
+ argParser.addOption("define", abbr: "D",
+ help: "Defines an environment constant for dart2js.",
+ allowMultiple: true, splitCommas: false);
+
argParser.addOption("format",
help: "How output should be displayed.",
allowed: ["text", "json"], defaultsTo: "text");
@@ -50,10 +54,16 @@ class BuildCommand extends BarbackCommand {
var errorsJson = [];
var logJson = [];
+ var environmentConstants = new Map.fromIterable(argResults["define"],
+ key: (pair) => pair.split("=").first,
+ value: (pair) => pair.split("=").last);
+
// Since this server will only be hit by the transformer loader and isn't
// user-facing, just use an IPv4 address to avoid a weird bug on the
// OS X buildbots.
- return AssetEnvironment.create(entrypoint, mode, useDart2JS: true)
+ return AssetEnvironment.create(entrypoint, mode,
+ environmentConstants: environmentConstants,
+ useDart2JS: true)
.then((environment) {
// Show in-progress errors, but not results. Those get handled
// implicitly by getAllAssets().
diff --git a/lib/src/command/serve.dart b/lib/src/command/serve.dart
index 32074fc90fbd20bb3479b8148d5a21c5cd091b42..c5b47469379f7a510c2f5288c34d6e165c6ae0c5 100644
--- a/lib/src/command/serve.dart
+++ b/lib/src/command/serve.dart
@@ -59,6 +59,9 @@ class ServeCommand extends BarbackCommand {
final _completer = new Completer();
ServeCommand() {
+ argParser.addOption("define", abbr: "D",
+ help: "Defines an environment constant for dart2js.",
+ allowMultiple: true, splitCommas: false);
argParser.addOption('hostname', defaultsTo: 'localhost',
help: 'The hostname to listen on.');
argParser.addOption('port', defaultsTo: '8080',
@@ -88,9 +91,13 @@ class ServeCommand extends BarbackCommand {
var watcherType = argResults['force-poll'] ?
WatcherType.POLLING : WatcherType.AUTO;
+ var environmentConstants = new Map.fromIterable(argResults["define"],
+ key: (pair) => pair.split("=").first,
+ value: (pair) => pair.split("=").last);
+
var environment = await AssetEnvironment.create(entrypoint, mode,
watcherType: watcherType, hostname: hostname, basePort: port,
- useDart2JS: useDart2JS);
+ useDart2JS: useDart2JS, environmentConstants: environmentConstants);
var directoryLength = sourceDirectories.map((dir) => dir.length)
.reduce(math.max);
diff --git a/lib/src/utils.dart b/lib/src/utils.dart
index 14d81a67a4138ea4e2c6aac75429c1a6cc05a132..d0eb936f7f818d5e0b4eac6013e3952cbb251cd0 100644
--- a/lib/src/utils.dart
+++ b/lib/src/utils.dart
@@ -371,6 +371,16 @@ Future<Map> mapFromIterableAsync(Iterable iter, {key(element),
})).then((_) => map);
}
+/// Returns a new map with all entries in both [map1] and [map2].
+///
+/// If there are overlapping keys, [map2]'s value wins.
+Map mergeMaps(Map map1, Map map2) {
+ var result = {};
+ result.addAll(map1);
+ result.addAll(map2);
+ return result;
+}
+
/// Returns the transitive closure of [graph].
///
/// This assumes [graph] represents a graph with a vertex for each key and an
diff --git a/test/dart2js/environment_constant_test.dart b/test/dart2js/environment_constant_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..dab1260f1abca74a83a6c0d0786caf98a5c46b0c
--- /dev/null
+++ b/test/dart2js/environment_constant_test.dart
@@ -0,0 +1,65 @@
+// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:scheduled_test/scheduled_test.dart';
+
+import '../descriptor.dart' as d;
+import '../serve/utils.dart';
+import '../test_pub.dart';
+
+main() {
+ initConfig();
+ group("passes environment constants to dart2js", () {
+ setUp(() {
+ // Dart2js can take a long time to compile dart code, so we increase the
+ // timeout to cope with that.
+ currentSchedule.timeout *= 3;
+
+ d.dir(appPath, [
+ d.appPubspec(),
+ d.dir('web', [
+ d.file('file.dart',
+ 'void main() => print(const String.fromEnvironment("name"));')
+ ])
+ ]).create();
+ });
+
+ integration('from "pub build"', () {
+ schedulePub(args: ["build", "--define", "name=fblthp"],
+ output: new RegExp(r'Built 1 file to "build".'));
+
+ d.dir(appPath, [
+ d.dir('build', [
+ d.dir('web', [
+ d.matcherFile('file.dart.js', contains('fblthp')),
+ ])
+ ])
+ ]).validate();
+ });
+
+ integration('from "pub serve"', () {
+ pubServe(args: ["--define", "name=fblthp"]);
+ requestShouldSucceed("file.dart.js", contains("fblthp"));
+ endPubServe();
+ });
+
+ integration('which takes precedence over the pubspec', () {
+ d.dir(appPath, [
+ d.pubspec({
+ "name": "myapp",
+ "transformers": [
+ {"\$dart2js": {"environment": {"name": "slartibartfast"}}}
+ ]
+ })
+ ]).create();
+
+ pubServe(args: ["--define", "name=fblthp"]);
+ requestShouldSucceed("file.dart.js", allOf([
+ contains("fblthp"),
+ isNot(contains("slartibartfast"))
+ ]));
+ endPubServe();
+ });
+ });
+}