Revert "Tweak public APIs and use them in patch_sdk, dart2js, and kernel-service."

pkg/front_end/lib/src/fasta/fasta.dart

Index: pkg/front_end/lib/src/fasta/fasta.dart
diff --git a/pkg/front_end/lib/src/fasta/fasta.dart b/pkg/front_end/lib/src/fasta/fasta.dart
index 0dfe70dcd31938925872ab4336a9cba52f8f8b56..865192b2aa6fed78a8eaa327703b6683a72d2e65 100644
--- a/pkg/front_end/lib/src/fasta/fasta.dart
+++ b/pkg/front_end/lib/src/fasta/fasta.dart
@@ -8,18 +8,23 @@ import 'dart:async' show Future;
 
 import 'dart:convert' show JSON;
 
-import 'dart:io' show BytesBuilder, File, exitCode;
+import 'dart:io' show BytesBuilder, Directory, File, exitCode;
 
+import 'package:front_end/file_system.dart';
 import 'package:front_end/physical_file_system.dart';
 import 'package:front_end/src/fasta/kernel/utils.dart';
+import 'package:kernel/binary/ast_to_binary.dart'
+    show LibraryFilteringBinaryPrinter;
 
-import 'package:kernel/kernel.dart' show Program, loadProgramFromBytes;
+import 'package:kernel/kernel.dart' show Library, Program, loadProgramFromBytes;
+
+import 'package:kernel/target/targets.dart' show Target;
 
 import 'compiler_command_line.dart' show CompilerCommandLine;
 
 import 'compiler_context.dart' show CompilerContext;
 
-import 'errors.dart' show InputError, inputError;
+import 'errors.dart' show InputError, formatUnexpected, inputError, reportCrash;
 
 import 'kernel/kernel_target.dart' show KernelTarget;
 
@@ -31,6 +36,8 @@ import 'ticker.dart' show Ticker;
 
 import 'translate_uri.dart' show TranslateUri;
 
+import 'vm.dart' show CompilationResult;
+
 const bool summary = const bool.fromEnvironment("summary", defaultValue: false);
 const int iterations = const int.fromEnvironment("iterations", defaultValue: 1);
 
@@ -164,6 +171,69 @@ class CompileTask {
   }
 }
 
+Future<CompilationResult> parseScript(
+    Uri fileName, Uri packages, Uri patchedSdk, Target backendTarget,
+    {bool verbose: false}) async {
+  return parseScriptInFileSystem(fileName, PhysicalFileSystem.instance,
+      packages, patchedSdk, backendTarget,
+      verbose: verbose);
+}
+
+Future<CompilationResult> parseScriptInFileSystem(Uri fileName,
+    FileSystem fileSystem, Uri packages, Uri patchedSdk, Target backendTarget,
+    {bool verbose: false}) async {
+  try {
+    if (!await fileSystem.entityForUri(fileName).exists()) {
+      return new CompilationResult.error(
+          formatUnexpected(fileName, -1, "No such file."));
+    }
+    if (!await new Directory.fromUri(patchedSdk).exists()) {
+      return new CompilationResult.error(
+          formatUnexpected(patchedSdk, -1, "Patched sdk directory not found."));
+    }
+
+    Program program;
+    try {
+      TranslateUri uriTranslator =
+          await TranslateUri.parse(fileSystem, patchedSdk, packages: packages);
+      final Ticker ticker = new Ticker(isVerbose: verbose);
+      final DillTarget dillTarget =
+          new DillTarget(ticker, uriTranslator, backendTarget);
+      _appendDillForUri(dillTarget, patchedSdk.resolve('platform.dill'));
+      final KernelTarget kernelTarget =
+          new KernelTarget(fileSystem, dillTarget, uriTranslator);
+      kernelTarget.read(fileName);
+      await dillTarget.buildOutlines();
+      await kernelTarget.buildOutlines();
+      program = await kernelTarget.buildProgram();
+      if (kernelTarget.errors.isNotEmpty) {
+        return new CompilationResult.errors(kernelTarget.errors);
+      }
+    } on InputError catch (e) {
+      return new CompilationResult.error(e.format());
+    }
+
+    if (program.mainMethod == null) {
+      return new CompilationResult.error("No 'main' method found.");
+    }
+
+    // Write the program to a list of bytes and return it.  Do not include
+    // libraries that have a dart: import URI.
+    //
+    // TODO(kmillikin): This is intended to exclude platform libraries that are
+    // included in the Kernel binary platform platform.dill.  It does not
+    // necessarily exclude exactly the platform libraries.  Use a better
+    // predicate that knows what is included in platform.dill.
+    var sink = new ByteSink();
+    bool predicate(Library library) => !library.importUri.isScheme('dart');
+    new LibraryFilteringBinaryPrinter(sink, predicate)
+        .writeProgramFile(program);
+    return new CompilationResult.ok(sink.builder.takeBytes());
+  } catch (e, s) {
+    return reportCrash(e, s, fileName);
+  }
+}
+
 Future compilePlatform(Uri patchedSdk, Uri fullOutput,
     {Uri outlineOutput,
     Uri packages,
@@ -183,16 +253,16 @@ Future compilePlatform(Uri patchedSdk, Uri fullOutput,
   });
 }
 
-// TODO(sigmund): reimplement this API using the directive listener intead.
-Future<List<Uri>> getDependencies(Uri script,
+Future writeDepsFile(Uri script, Uri depsFile, Uri output,
     {Uri sdk,
     Uri packages,
     Uri platform,
+    Iterable<Uri> extraDependencies,
     bool verbose: false,
     String backendTarget}) async {
   backendTarget ??= "vm_fasta";
   Ticker ticker = new Ticker(isVerbose: verbose);
-  return await CompilerCommandLine.withGlobalOptions("", [""],
+  await CompilerCommandLine.withGlobalOptions("", [""],
       (CompilerContext c) async {
     c.options.options["--target"] = backendTarget;
     c.options.options["--strong-mode"] = false;
@@ -208,14 +278,15 @@ Future<List<Uri>> getDependencies(Uri script,
     ticker.logMs("Read packages file");
     DillTarget dillTarget =
         new DillTarget(ticker, uriTranslator, c.options.target);
-    if (platform != null) _appendDillForUri(dillTarget, platform);
+    _appendDillForUri(dillTarget, platform);
     KernelTarget kernelTarget = new KernelTarget(
         PhysicalFileSystem.instance, dillTarget, uriTranslator, c.uriToSource);
 
     kernelTarget.read(script);
     await dillTarget.buildOutlines();
     await kernelTarget.loader.buildOutlines();
-    return await kernelTarget.loader.getDependencies();
+    await kernelTarget.writeDepsFile(output, depsFile,
+        extraDependencies: extraDependencies);
   });
 }