[CFE] Language versioning max/default also setable via compiler options

* Max and default for language version controllable via language options
* Default (if not set) comes from kernel static fields
* Kernel static fields updated to 2.6
* (Also set version for debug expression library)
* Test added that checks that the kernel static fields aren't out-of-date
  (checked against python script "tools/make_version.py").

Change-Id: I65f26053081e4c55c215b677128f37fa970693c6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/114944
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Jens Johansen <jensj@google.com>

pkg/front_end/lib/src/api_prototype/compiler_options.dart

@@ -4,6 +4,8 @@
 
 library front_end.compiler_options;
 
+import 'package:kernel/ast.dart' as kernel show Library;
+
 import 'package:kernel/target/targets.dart' show Target;
 
 import 'diagnostic_message.dart' show DiagnosticMessageHandler;
@@ -215,6 +217,13 @@ class CompilerOptions {
 
   /// Whether to write a file (e.g. a dill file) when reporting a crash.
   bool writeFileOnCrashReport = true;
+
+  /// The current sdk version string, e.g. "2.6.0-edge.sha1hash".
+  /// For instance used for language versioning (specifying the maximum
+  /// version).
+  String currentSdkVersion = "${kernel.Library.defaultLanguageVersionMajor}"
+      "."
+      "${kernel.Library.defaultLanguageVersionMinor}";
 }
 
 /// Parse experimental flag arguments of the form 'flag' or 'no-flag' into a map

pkg/front_end/lib/src/base/processed_options.dart

@@ -306,6 +306,11 @@ class ProcessedOptions {
   /// Whether to write a file (e.g. a dill file) when reporting a crash.
   bool get writeFileOnCrashReport => _raw.writeFileOnCrashReport;
 
+  /// The current sdk version string, e.g. "2.6.0-edge.sha1hash".
+  /// For instance used for language versioning (specifying the maximum
+  /// version).
+  String get currentSdkVersion => _raw.currentSdkVersion;
+
   Target _target;
   Target get target => _target ??=
       _raw.target ?? new NoneTarget(new TargetFlags(legacyMode: legacyMode));

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

@@ -861,6 +861,9 @@ class IncrementalCompiler implements IncrementalKernelGenerator {
         scope: libraryBuilder.scope.createNestedScope("expression"),
         nameOrigin: libraryBuilder.library,
       );
+      debugLibrary.setLanguageVersion(
+          libraryBuilder.library.languageVersionMajor,
+          libraryBuilder.library.languageVersionMinor);
 
       if (libraryBuilder is DillLibraryBuilder) {
         for (LibraryDependency dependency

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

@@ -78,8 +78,11 @@ Uint8List serializeComponent(Component component,
 const String kDebugClassName = "#DebugClass";
 
 Component createExpressionEvaluationComponent(Procedure procedure) {
-  Library fakeLibrary =
-      new Library(new Uri(scheme: 'evaluate', path: 'source'));
+  Library realLibrary = procedure.enclosingLibrary;
+
+  Library fakeLibrary = new Library(new Uri(scheme: 'evaluate', path: 'source'))
+    ..setLanguageVersion(
+        realLibrary.languageVersionMajor, realLibrary.languageVersionMinor);
 
   if (procedure.parent is Class) {
     Class realClass = procedure.parent;

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

@@ -358,7 +358,9 @@ class SourceLibraryBuilder extends LibraryBuilder {
             scope,
             actualOrigin,
             target ??
-                (actualOrigin?.library ?? new Library(uri, fileUri: fileUri)),
+                (actualOrigin?.library ?? new Library(uri, fileUri: fileUri)
+                  ..setLanguageVersion(loader.target.currentSdkVersionMajor,
+                      loader.target.currentSdkVersionMinor)),
             nameOrigin);
 
   @override
@@ -377,7 +379,7 @@ class SourceLibraryBuilder extends LibraryBuilder {
 
   @override
   void setLanguageVersion(int major, int minor,
-      {int offset: 0, int length: noLength, bool explicit}) {
+      {int offset: 0, int length: noLength, bool explicit: false}) {
     if (languageVersionExplicitlySet) return;
     if (explicit) languageVersionExplicitlySet = true;
 
@@ -387,15 +389,15 @@ class SourceLibraryBuilder extends LibraryBuilder {
       return;
     }
 
-    // If trying to set a langauge version that is higher than the "sdk-one"
-    // it's an error.
-    if (major > Library.defaultLanguageVersionMajor ||
-        (major == Library.defaultLanguageVersionMajor &&
-            minor > Library.defaultLanguageVersionMinor)) {
+    // If trying to set a langauge version that is higher than the current sdk
+    // version it's an error.
+    if (major > loader.target.currentSdkVersionMajor ||
+        (major == loader.target.currentSdkVersionMajor &&
+            minor > loader.target.currentSdkVersionMinor)) {
       addPostponedProblem(
           templateLanguageVersionTooHigh.withArguments(
-              Library.defaultLanguageVersionMajor,
-              Library.defaultLanguageVersionMinor),
+              loader.target.currentSdkVersionMajor,
+              loader.target.currentSdkVersionMinor),
           offset,
           length,
           fileUri);

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

@@ -214,9 +214,6 @@ class SourceLoader extends Loader {
             enableExtensionMethods: target.enableExtensionMethods,
             enableNonNullable: target.enableNonNullable),
         languageVersionChanged: (_, LanguageVersionToken version) {
-      // TODO(jensj): What if we have several? What if it is unsupported?
-      // What if the language version was already set via packages and this is
-      // higher? Etc
       library.setLanguageVersion(version.major, version.minor,
           offset: version.offset, length: version.length, explicit: true);
     });

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

@@ -153,4 +153,37 @@ abstract class TargetImplementation extends Target {
     }
     return rewriteSeverity(severity, message.code, fileUri);
   }
+
+  String get currentSdkVersion {
+    return CompilerContext.current.options.currentSdkVersion;
+  }
+
+  int _currentSdkVersionMajor;
+  int _currentSdkVersionMinor;
+  int get currentSdkVersionMajor {
+    if (_currentSdkVersionMajor != null) return _currentSdkVersionMajor;
+    _parseCurrentSdkVersion();
+    return _currentSdkVersionMajor;
+  }
+
+  int get currentSdkVersionMinor {
+    if (_currentSdkVersionMinor != null) return _currentSdkVersionMinor;
+    _parseCurrentSdkVersion();
+    return _currentSdkVersionMinor;
+  }
+
+  void _parseCurrentSdkVersion() {
+    bool good = false;
+    if (currentSdkVersion != null) {
+      List<String> dotSeparatedParts = currentSdkVersion.split(".");
+      if (dotSeparatedParts.length >= 2) {
+        _currentSdkVersionMajor = int.tryParse(dotSeparatedParts[0]);
+        _currentSdkVersionMinor = int.tryParse(dotSeparatedParts[1]);
+        good = true;
+      }
+    }
+    if (!good) {
+      throw new StateError("Unparsable sdk version given: $currentSdkVersion");
+    }
+  }
 }

pkg/front_end/lib/src/testing/id_testing_helper.dart

@@ -44,6 +44,8 @@ class TestConfig {
   final Map<ExperimentalFlag, bool> experimentalFlags;
 
   const TestConfig(this.marker, this.name, {this.experimentalFlags = const {}});
+
+  void customizeCompilerOptions(CompilerOptions options) {}
 }
 
 // TODO(johnniwinther): Support annotations for compile-time errors.
@@ -240,6 +242,7 @@ Future<bool> runTestForConfig<T>(
   };
   options.debugDump = printCode;
   options.experimentalFlags.addAll(config.experimentalFlags);
+  config.customizeCompilerOptions(options);
   InternalCompilerResult compilerResult = await compileScript(
       testData.memorySourceFiles,
       options: options,

pkg/front_end/test/language_versioning/language_versioning_test.dart

@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:io' show Directory, Platform;
+import 'package:front_end/src/api_prototype/compiler_options.dart';
 import 'package:front_end/src/fasta/messages.dart' show FormattedMessage;
 import 'package:front_end/src/testing/id.dart' show ActualData, Id;
 import 'package:front_end/src/testing/id_testing.dart'
@@ -11,9 +12,9 @@ import 'package:front_end/src/testing/id_testing.dart';
 import 'package:front_end/src/testing/id_testing_helper.dart'
     show
         CfeDataExtractor,
-        InternalCompilerResult,
         DataComputer,
-        defaultCfeConfig,
+        InternalCompilerResult,
+        TestConfig,
         createUriForFileName,
         onFailure,
         runTestFor;
@@ -21,8 +22,9 @@ import 'package:kernel/ast.dart' show Library;
 
 main(List<String> args) async {
   // Fix default/max major and minor version so we can test it.
-  Library.defaultLanguageVersionMajor = 2;
-  Library.defaultLanguageVersionMinor = 8;
+  // This config sets it to 2.8.
+  TestConfigWithLanguageVersion cfeConfig =
+      new TestConfigWithLanguageVersion(cfeMarker, "cfe");
 
   Directory dataDir = new Directory.fromUri(Platform.script.resolve('data'));
   await runTests(dataDir,
@@ -30,8 +32,17 @@ main(List<String> args) async {
       supportedMarkers: [cfeMarker],
       createUriForFileName: createUriForFileName,
       onFailure: onFailure,
-      runTest: runTestFor(
-          const LanguageVersioningDataComputer(), [defaultCfeConfig]));
+      runTest: runTestFor(const LanguageVersioningDataComputer(), [cfeConfig]));
+}
+
+class TestConfigWithLanguageVersion extends TestConfig {
+  TestConfigWithLanguageVersion(String marker, String name)
+      : super(marker, name);
+
+  @override
+  void customizeCompilerOptions(CompilerOptions options) {
+    options.currentSdkVersion = "2.8";
+  }
 }
 
 class LanguageVersioningDataComputer extends DataComputer<String> {

pkg/front_end/test/language_versioning/language_versioning_up_to_date_test.dart

@@ -0,0 +1,61 @@
+// Copyright (c) 2019, 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 'dart:io' show Platform, Process, ProcessResult;
+import 'package:front_end/src/api_prototype/compiler_options.dart';
+import 'package:kernel/ast.dart' as kernel show Library;
+
+import '../utils/io_utils.dart';
+
+final String repoDir = computeRepoDir();
+
+String get dartVm => Platform.executable;
+
+main(List<String> args) async {
+  ProcessResult result = await Process.run(
+      "python", ["tools/make_version.py", "--no_git", "-q"],
+      workingDirectory: repoDir);
+
+  String stdout = result.stdout.toString();
+  String stderr = result.stderr.toString();
+  int exitCode = result.exitCode;
+
+  print("--- stdout ---");
+  print(stdout);
+  print("--- stderr ---");
+  print(stderr);
+  print("---exit code ---");
+  print(exitCode);
+
+  // E.g. "2.6.0-edge" (without the quotes).
+  String versionString = stdout.split("\n")[0];
+  List<String> dotSeparatedParts = versionString.split(".");
+  int major = int.tryParse(dotSeparatedParts[0]);
+  int minor = int.tryParse(dotSeparatedParts[1]);
+
+  if (kernel.Library.defaultLanguageVersionMajor != major ||
+      kernel.Library.defaultLanguageVersionMinor != minor) {
+    throw "Kernel defaults "
+        "${kernel.Library.defaultLanguageVersionMajor}"
+        "."
+        "${kernel.Library.defaultLanguageVersionMinor}"
+        " does not match output from make_version.py ($major.$minor)";
+  } else {
+    print("Kernel version matches.");
+  }
+
+  CompilerOptions compilerOptions = new CompilerOptions();
+
+  List<String> dotSeparatedPartsFromOptions =
+      compilerOptions.currentSdkVersion.split(".");
+  int majorFromOptions = int.tryParse(dotSeparatedPartsFromOptions[0]);
+  int minorFromOptions = int.tryParse(dotSeparatedPartsFromOptions[1]);
+  if (majorFromOptions != major || minorFromOptions != minor) {
+    throw "CompilerOptions defaults "
+        "${majorFromOptions}.${minorFromOptions}"
+        " does not match output from make_version.py ($major.$minor)";
+  } else {
+    print("CompilerOptions default version matches.");
+  }
+}

pkg/front_end/test/spell_checking_list_code.txt

@@ -709,6 +709,7 @@ server
 service
 setaf
 sh
+sha1hash
 shadowed
 shallow
 shas

pkg/front_end/test/spell_checking_list_common.txt

@@ -621,6 +621,7 @@ curly
 current
 currently
 custom
+customize
 cyan
 cycle
 cycles
@@ -1623,6 +1624,7 @@ mathematical
 matter
 maturity
 max
+maximum
 may
 maybe
 mean
@@ -2828,6 +2830,7 @@ unmodified
 unnamed
 unnecessarily
 unnecessary
+unparsable
 unpromoted
 unread
 unrecognized
@@ -2901,6 +2904,7 @@ verifies
 verify
 verifying
 version
+versioning
 versions
 vertex
 vertical

pkg/front_end/test/spell_checking_list_tests.txt

@@ -270,6 +270,7 @@ pubspec
 pv
 px
 py
+python
 quot
 r"\s
 rd

pkg/kernel/lib/ast.dart

@@ -280,7 +280,7 @@ class Library extends NamedNode
 
   // TODO(jensj): Do we have a better option than this?
   static int defaultLanguageVersionMajor = 2;
-  static int defaultLanguageVersionMinor = 4;
+  static int defaultLanguageVersionMinor = 6;
 
   int _languageVersionMajor;
   int _languageVersionMinor;