Add experiment flag inference-update-3.

I plan to use this to guard my work on
https://github.com/dart-lang/language/issues/3471.

Bug: https://github.com/dart-lang/language/issues/3471
Change-Id: I49afae7260c14b8c6b646ccc0ee39efae3891c34
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/338649
Reviewed-by: Michael Thomsen <mit@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>

pkg/_fe_analyzer_shared/lib/src/experiments/flags.dart

@@ -80,6 +80,13 @@ enum ExperimentalFlag {
       experimentEnabledVersion: const Version(3, 2),
       experimentReleasedVersion: const Version(3, 2)),
 
+  inferenceUpdate3(
+      name: 'inference-update-3',
+      isEnabledByDefault: false,
+      isExpired: false,
+      experimentEnabledVersion: defaultLanguageVersion,
+      experimentReleasedVersion: defaultLanguageVersion),
+
   inlineClass(
       name: 'inline-class',
       isEnabledByDefault: true,

pkg/analyzer/lib/dart/analysis/features.dart

@@ -40,6 +40,9 @@ abstract class Feature {
   /// Feature information for inference-update-2.
   static final inference_update_2 = ExperimentalFeatures.inference_update_2;
 
+  /// Feature information for inference-update-3.
+  static final inference_update_3 = ExperimentalFeatures.inference_update_3;
+
   /// Feature information for inline classes.
   static final inline_class = ExperimentalFeatures.inline_class;
 

pkg/analyzer/lib/src/dart/analysis/driver.dart

@@ -88,7 +88,7 @@ import 'package:analyzer/src/utilities/uri_cache.dart';
 // TODO(scheglov): Clean up the list of implicitly analyzed files.
 class AnalysisDriver implements AnalysisDriverGeneric {
   /// The version of data format, should be incremented on every format change.
-  static const int DATA_VERSION = 322;
+  static const int DATA_VERSION = 323;
 
   /// The number of exception contexts allowed to write. Once this field is
   /// zero, we stop writing any new exception contexts in this process.

pkg/analyzer/lib/src/dart/analysis/experiments.g.dart

@@ -27,6 +27,7 @@ final _knownFeatures = <String, ExperimentalFeature>{
   EnableString.generic_metadata: ExperimentalFeatures.generic_metadata,
   EnableString.inference_update_1: ExperimentalFeatures.inference_update_1,
   EnableString.inference_update_2: ExperimentalFeatures.inference_update_2,
+  EnableString.inference_update_3: ExperimentalFeatures.inference_update_3,
   EnableString.inline_class: ExperimentalFeatures.inline_class,
   EnableString.macros: ExperimentalFeatures.macros,
   EnableString.named_arguments_anywhere:
@@ -81,6 +82,9 @@ class EnableString {
   /// String to enable the experiment "inference-update-2"
   static const String inference_update_2 = 'inference-update-2';
 
+  /// String to enable the experiment "inference-update-3"
+  static const String inference_update_3 = 'inference-update-3';
+
   /// String to enable the experiment "inline-class"
   static const String inline_class = 'inline-class';
 
@@ -238,8 +242,19 @@ class ExperimentalFeatures {
     releaseVersion: Version.parse('3.2.0'),
   );
 
-  static final inline_class = ExperimentalFeature(
+  static final inference_update_3 = ExperimentalFeature(
     index: 10,
+    enableString: EnableString.inference_update_3,
+    isEnabledByDefault: IsEnabledByDefault.inference_update_3,
+    isExpired: IsExpired.inference_update_3,
+    documentation:
+        'Better handling of coercions, conditional expressions, and switch expressions.',
+    experimentalReleaseVersion: null,
+    releaseVersion: null,
+  );
+
+  static final inline_class = ExperimentalFeature(
+    index: 11,
     enableString: EnableString.inline_class,
     isEnabledByDefault: IsEnabledByDefault.inline_class,
     isExpired: IsExpired.inline_class,
@@ -249,7 +264,7 @@ class ExperimentalFeatures {
   );
 
   static final macros = ExperimentalFeature(
-    index: 11,
+    index: 12,
     enableString: EnableString.macros,
     isEnabledByDefault: IsEnabledByDefault.macros,
     isExpired: IsExpired.macros,
@@ -259,7 +274,7 @@ class ExperimentalFeatures {
   );
 
   static final named_arguments_anywhere = ExperimentalFeature(
-    index: 12,
+    index: 13,
     enableString: EnableString.named_arguments_anywhere,
     isEnabledByDefault: IsEnabledByDefault.named_arguments_anywhere,
     isExpired: IsExpired.named_arguments_anywhere,
@@ -269,7 +284,7 @@ class ExperimentalFeatures {
   );
 
   static final native_assets = ExperimentalFeature(
-    index: 13,
+    index: 14,
     enableString: EnableString.native_assets,
     isEnabledByDefault: IsEnabledByDefault.native_assets,
     isExpired: IsExpired.native_assets,
@@ -279,7 +294,7 @@ class ExperimentalFeatures {
   );
 
   static final non_nullable = ExperimentalFeature(
-    index: 14,
+    index: 15,
     enableString: EnableString.non_nullable,
     isEnabledByDefault: IsEnabledByDefault.non_nullable,
     isExpired: IsExpired.non_nullable,
@@ -289,7 +304,7 @@ class ExperimentalFeatures {
   );
 
   static final nonfunction_type_aliases = ExperimentalFeature(
-    index: 15,
+    index: 16,
     enableString: EnableString.nonfunction_type_aliases,
     isEnabledByDefault: IsEnabledByDefault.nonfunction_type_aliases,
     isExpired: IsExpired.nonfunction_type_aliases,
@@ -299,7 +314,7 @@ class ExperimentalFeatures {
   );
 
   static final patterns = ExperimentalFeature(
-    index: 16,
+    index: 17,
     enableString: EnableString.patterns,
     isEnabledByDefault: IsEnabledByDefault.patterns,
     isExpired: IsExpired.patterns,
@@ -309,7 +324,7 @@ class ExperimentalFeatures {
   );
 
   static final records = ExperimentalFeature(
-    index: 17,
+    index: 18,
     enableString: EnableString.records,
     isEnabledByDefault: IsEnabledByDefault.records,
     isExpired: IsExpired.records,
@@ -319,7 +334,7 @@ class ExperimentalFeatures {
   );
 
   static final resource_identifiers = ExperimentalFeature(
-    index: 18,
+    index: 19,
     enableString: EnableString.resource_identifiers,
     isEnabledByDefault: IsEnabledByDefault.resource_identifiers,
     isExpired: IsExpired.resource_identifiers,
@@ -329,7 +344,7 @@ class ExperimentalFeatures {
   );
 
   static final sealed_class = ExperimentalFeature(
-    index: 19,
+    index: 20,
     enableString: EnableString.sealed_class,
     isEnabledByDefault: IsEnabledByDefault.sealed_class,
     isExpired: IsExpired.sealed_class,
@@ -339,7 +354,7 @@ class ExperimentalFeatures {
   );
 
   static final set_literals = ExperimentalFeature(
-    index: 20,
+    index: 21,
     enableString: EnableString.set_literals,
     isEnabledByDefault: IsEnabledByDefault.set_literals,
     isExpired: IsExpired.set_literals,
@@ -349,7 +364,7 @@ class ExperimentalFeatures {
   );
 
   static final spread_collections = ExperimentalFeature(
-    index: 21,
+    index: 22,
     enableString: EnableString.spread_collections,
     isEnabledByDefault: IsEnabledByDefault.spread_collections,
     isExpired: IsExpired.spread_collections,
@@ -359,7 +374,7 @@ class ExperimentalFeatures {
   );
 
   static final super_parameters = ExperimentalFeature(
-    index: 22,
+    index: 23,
     enableString: EnableString.super_parameters,
     isEnabledByDefault: IsEnabledByDefault.super_parameters,
     isExpired: IsExpired.super_parameters,
@@ -369,7 +384,7 @@ class ExperimentalFeatures {
   );
 
   static final test_experiment = ExperimentalFeature(
-    index: 23,
+    index: 24,
     enableString: EnableString.test_experiment,
     isEnabledByDefault: IsEnabledByDefault.test_experiment,
     isExpired: IsExpired.test_experiment,
@@ -380,7 +395,7 @@ class ExperimentalFeatures {
   );
 
   static final triple_shift = ExperimentalFeature(
-    index: 24,
+    index: 25,
     enableString: EnableString.triple_shift,
     isEnabledByDefault: IsEnabledByDefault.triple_shift,
     isExpired: IsExpired.triple_shift,
@@ -390,7 +405,7 @@ class ExperimentalFeatures {
   );
 
   static final unnamed_libraries = ExperimentalFeature(
-    index: 25,
+    index: 26,
     enableString: EnableString.unnamed_libraries,
     isEnabledByDefault: IsEnabledByDefault.unnamed_libraries,
     isExpired: IsExpired.unnamed_libraries,
@@ -400,7 +415,7 @@ class ExperimentalFeatures {
   );
 
   static final variance = ExperimentalFeature(
-    index: 26,
+    index: 27,
     enableString: EnableString.variance,
     isEnabledByDefault: IsEnabledByDefault.variance,
     isExpired: IsExpired.variance,
@@ -443,6 +458,9 @@ class IsEnabledByDefault {
   /// Default state of the experiment "inference-update-2"
   static const bool inference_update_2 = true;
 
+  /// Default state of the experiment "inference-update-3"
+  static const bool inference_update_3 = false;
+
   /// Default state of the experiment "inline-class"
   static const bool inline_class = true;
 
@@ -529,6 +547,9 @@ class IsExpired {
   /// Expiration status of the experiment "inference-update-2"
   static const bool inference_update_2 = false;
 
+  /// Expiration status of the experiment "inference-update-3"
+  static const bool inference_update_3 = false;
+
   /// Expiration status of the experiment "inline-class"
   static const bool inline_class = false;
 
@@ -618,6 +639,10 @@ mixin _CurrentState {
   bool get inference_update_2 =>
       isEnabled(ExperimentalFeatures.inference_update_2);
 
+  /// Current state for the flag "inference-update-3"
+  bool get inference_update_3 =>
+      isEnabled(ExperimentalFeatures.inference_update_3);
+
   /// Current state for the flag "inline-class"
   bool get inline_class => isEnabled(ExperimentalFeatures.inline_class);
 

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

@@ -139,6 +139,14 @@ class ExperimentalFlag {
       experimentEnabledVersion: const Version(3, 2),
       experimentReleasedVersion: const Version(3, 2));
 
+  static const ExperimentalFlag inferenceUpdate3 = const ExperimentalFlag(
+      name: 'inference-update-3',
+      isEnabledByDefault: false,
+      isExpired: false,
+      enabledVersion: defaultLanguageVersion,
+      experimentEnabledVersion: defaultLanguageVersion,
+      experimentReleasedVersion: defaultLanguageVersion);
+
   static const ExperimentalFlag inlineClass = const ExperimentalFlag(
       name: 'inline-class',
       isEnabledByDefault: true,
@@ -366,6 +374,10 @@ class GlobalFeatures {
   GlobalFeature get inferenceUpdate2 => _inferenceUpdate2 ??=
       _computeGlobalFeature(ExperimentalFlag.inferenceUpdate2);
 
+  GlobalFeature? _inferenceUpdate3;
+  GlobalFeature get inferenceUpdate3 => _inferenceUpdate3 ??=
+      _computeGlobalFeature(ExperimentalFlag.inferenceUpdate3);
+
   GlobalFeature? _inlineClass;
   GlobalFeature get inlineClass =>
       _inlineClass ??= _computeGlobalFeature(ExperimentalFlag.inlineClass);
@@ -504,6 +516,11 @@ class LibraryFeatures {
       _inferenceUpdate2 ??= globalFeatures._computeLibraryFeature(
           ExperimentalFlag.inferenceUpdate2, canonicalUri, libraryVersion);
 
+  LibraryFeature? _inferenceUpdate3;
+  LibraryFeature get inferenceUpdate3 =>
+      _inferenceUpdate3 ??= globalFeatures._computeLibraryFeature(
+          ExperimentalFlag.inferenceUpdate3, canonicalUri, libraryVersion);
+
   LibraryFeature? _inlineClass;
   LibraryFeature get inlineClass =>
       _inlineClass ??= globalFeatures._computeLibraryFeature(
@@ -617,6 +634,8 @@ class LibraryFeatures {
         return inferenceUpdate1;
       case shared.ExperimentalFlag.inferenceUpdate2:
         return inferenceUpdate2;
+      case shared.ExperimentalFlag.inferenceUpdate3:
+        return inferenceUpdate3;
       case shared.ExperimentalFlag.inlineClass:
         return inlineClass;
       case shared.ExperimentalFlag.macros:
@@ -682,6 +701,8 @@ ExperimentalFlag? parseExperimentalFlag(String flag) {
       return ExperimentalFlag.inferenceUpdate1;
     case "inference-update-2":
       return ExperimentalFlag.inferenceUpdate2;
+    case "inference-update-3":
+      return ExperimentalFlag.inferenceUpdate3;
     case "inline-class":
       return ExperimentalFlag.inlineClass;
     case "macros":
@@ -743,6 +764,8 @@ final Map<ExperimentalFlag, bool> defaultExperimentalFlags = {
       ExperimentalFlag.inferenceUpdate1.isEnabledByDefault,
   ExperimentalFlag.inferenceUpdate2:
       ExperimentalFlag.inferenceUpdate2.isEnabledByDefault,
+  ExperimentalFlag.inferenceUpdate3:
+      ExperimentalFlag.inferenceUpdate3.isEnabledByDefault,
   ExperimentalFlag.inlineClass: ExperimentalFlag.inlineClass.isEnabledByDefault,
   ExperimentalFlag.macros: ExperimentalFlag.macros.isEnabledByDefault,
   ExperimentalFlag.namedArgumentsAnywhere:
@@ -796,6 +819,7 @@ const Map<shared.ExperimentalFlag, ExperimentalFlag> sharedExperimentalFlags = {
   shared.ExperimentalFlag.genericMetadata: ExperimentalFlag.genericMetadata,
   shared.ExperimentalFlag.inferenceUpdate1: ExperimentalFlag.inferenceUpdate1,
   shared.ExperimentalFlag.inferenceUpdate2: ExperimentalFlag.inferenceUpdate2,
+  shared.ExperimentalFlag.inferenceUpdate3: ExperimentalFlag.inferenceUpdate3,
   shared.ExperimentalFlag.inlineClass: ExperimentalFlag.inlineClass,
   shared.ExperimentalFlag.macros: ExperimentalFlag.macros,
   shared.ExperimentalFlag.namedArgumentsAnywhere:

tools/experimental_features.yaml

@@ -128,6 +128,9 @@ features:
   resource-identifiers:
     help: "Output arguments used by static functions."
 
+  inference-update-3:
+    help: "Better handling of coercions, conditional expressions, and switch expressions."
+
 # Experiment flag only used for testing.
   test-experiment:
     help: >-