update kernel worker to support -D environment defines

Change-Id: Ic73cfcc8dc0bd8b721733e0696b028aa572125e0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121927
Reviewed-by: Johnni Winther <[email protected]>
Commit-Queue: Jake Macdonald <[email protected]>

Author: jakemac53

pkg/front_end/lib/src/api_unstable/bazel_worker.dart

@@ -68,6 +68,7 @@ Future<InitializedCompilerState> initializeIncrementalCompiler(
     FileSystem fileSystem,
     Iterable<String> experiments,
     bool outlineOnly,
+    Map<String, String> environmentDefines,
     {bool trackNeededDillLibraries: false}) async {
   List<Component> outputLoadedInputSummaries =
       new List<Component>(summaryInputs.length);
@@ -88,7 +89,8 @@ Future<InitializedCompilerState> initializeIncrementalCompiler(
       experimentalFlags: experimentalFlags,
       outlineOnly: outlineOnly,
       omitPlatform: true,
-      trackNeededDillLibraries: trackNeededDillLibraries);
+      trackNeededDillLibraries: trackNeededDillLibraries,
+      environmentDefines: environmentDefines);
 }
 
 Future<InitializedCompilerState> initializeCompiler(
@@ -100,7 +102,8 @@ Future<InitializedCompilerState> initializeCompiler(
     List<Uri> linkedInputs,
     Target target,
     FileSystem fileSystem,
-    Iterable<String> experiments) async {
+    Iterable<String> experiments,
+    Map<String, String> environmentDefines) async {
   // TODO(sigmund): use incremental compiler when it supports our use case.
   // Note: it is common for the summary worker to invoke the compiler with the
   // same input summary URIs, but with different contents, so we'd need to be
@@ -114,7 +117,7 @@ Future<InitializedCompilerState> initializeCompiler(
     ..linkedDependencies = linkedInputs
     ..target = target
     ..fileSystem = fileSystem
-    ..environmentDefines = const {}
+    ..environmentDefines = environmentDefines
     ..experimentalFlags = parseExperimentalFlags(
         parseExperimentalArguments(experiments),
         onError: (e) => throw e);

utils/bazel/kernel_worker.dart

@@ -142,7 +142,8 @@ final summaryArgsParser = new ArgParser()
   ..addOption('used-inputs')
   ..addFlag('track-widget-creation', defaultsTo: false)
   ..addMultiOption('enable-experiment',
-      help: 'Enable a language experiment when invoking the CFE.');
+      help: 'Enable a language experiment when invoking the CFE.')
+  ..addMultiOption('define', abbr: 'D');
 
 class ComputeKernelResult {
   final bool succeeded;
@@ -166,6 +167,7 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
     fe.InitializedCompilerState previousState}) async {
   dynamic out = outputBuffer ?? stderr;
   bool succeeded = true;
+
   var parsedArgs = summaryArgsParser.parse(args);
 
   if (parsedArgs['help']) {
@@ -244,6 +246,8 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
   fe.InitializedCompilerState state;
   bool usingIncrementalCompiler = false;
   bool recordUsedInputs = parsedArgs["used-inputs"] != null;
+  var environmentDefines = _parseEnvironmentDefines(parsedArgs['define']);
+
   if (parsedArgs['use-incremental-compiler']) {
     usingIncrementalCompiler = true;
 
@@ -286,6 +290,7 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
         fileSystem,
         (parsedArgs['enable-experiment'] as List<String>),
         summaryOnly,
+        environmentDefines,
         trackNeededDillLibraries: recordUsedInputs);
   } else {
     state = await fe.initializeCompiler(
@@ -298,7 +303,8 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
         linkedInputs,
         target,
         fileSystem,
-        (parsedArgs['enable-experiment'] as List<String>));
+        parsedArgs['enable-experiment'] as List<String>,
+        environmentDefines);
   }
 
   void onDiagnostic(fe.DiagnosticMessage message) {
@@ -448,3 +454,20 @@ Uri _toUri(String uriString) {
   // concatenated with Unix-style paths.
   return Uri.base.resolve(uriString.replaceAll("\\", "/"));
 }
+
+Map<String, String> _parseEnvironmentDefines(List<String> args) {
+  var environment = <String, String>{};
+
+  for (var arg in args) {
+    var eq = arg.indexOf('=');
+    if (eq <= 0) {
+      var kind = eq == 0 ? 'name' : 'value';
+      throw FormatException('no $kind given to -D option `$arg`');
+    }
+    var name = arg.substring(0, eq);
+    var value = arg.substring(eq + 1);
+    environment[name] = value;
+  }
+
+  return environment;
+}