Initial API for the Dart front_end package.

pkg/front_end/lib/kernel_generator.dart

Index: pkg/front_end/lib/kernel_generator.dart
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+// Copyright (c) 2016, 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.
+
+/// Defines the front-end API for converting source code to Dart Kernel objects.
+library front_end.kernel_generator;
+
+import 'dart:async';
+import 'compiler_options.dart';
+import 'package:kernel/kernel.dart' as kernel;
+
+/// Generates a kernel representation of the program whose main library is in
+/// the given [source].
+///
+/// Intended for whole program (non-modular) compilation.
+///
+/// Given the Uri of a file containing a program's `main` method, this function
+/// follows `import`, `export`, and `part` declarations to discover the whole
+/// program, and converts the result to Dart Kernel format.
+///
+/// If summaries are provided in [options], they may be used to speed up
+/// analysis, but they will not take the place of Dart source code (since the
+/// Dart source code is still needed to access the contents of method bodies).
+///
+/// TODO(paulberry): will the VM have a pickled version of the SDK inside it? If
+/// so, then maybe this method should not convert SDK libraries to kernel.
+Future<kernel.Program> kernelForProgram(Uri source, CompilerOptions options) =>
+    throw new UnimplementedError();
+
+/// Generates a kernel representation of the build unit whose source files are
+/// in [sources].
+///
+/// Intended for modular compilation.
+///
+/// [sources] should be the complete set of source files for a build unit
+/// (including both library and part files).  All of the library files are
+/// transformed into Dart Kernel Library objects.
+///
+/// The compilation process is hermetic, meaning that the only files which will
+/// be read are those listed in [sources], [CompilerOptions.inputSummaries], and
+/// [CompilerOptions.sdkSummary].  If a source file attempts to refer to a file
+/// which is not obtainable from these paths, that will result in an error, even
+/// if the file exists on the filesystem.
+///
+/// Any `part` declarations found in [sources] must refer to part files which
+/// are also listed in [sources], otherwise an error results.  (It is not
+/// permitted to refer to a part file declared in another build unit).
+///
+/// The return value is a [kernel.Program] object with no main method set.
+/// TODO(paulberry): would it be better to define a data type in kernel to
+/// represent a bundle of all the libraries in a given build unit?
+///
+/// TODO(paulberry): does additional information need to be output to allow the
+/// caller to match up referenced elements to the summary files they were
+/// obtained from?
+Future<kernel.Program> kernelForBuildUnit(
+        List<Uri> sources, CompilerOptions options) =>
+    throw new UnimplementedError();