Store type Never in summaries.

scheglov · commit-bot@chromium.org · commit ce7232cd0f7a · 2019-07-23T19:30:20.000Z
R=brianwilkerson@google.com, paulberry@google.com Change-Id: I2b0e7cc86844caf2613a8c3e5ea00ce4576e6e8f Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/109987 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
diff --git a/pkg/analyzer/lib/src/summary/resynthesize.dart b/pkg/analyzer/lib/src/summary/resynthesize.dart
@@ -1559,7 +1559,15 @@ class _UnitResynthesizer extends UnitResynthesizer with UnitResynthesizerMixin {
         }
         switch (linkedReference.kind) {
           case ReferenceKind.classOrEnum:
-            element = new ClassElementHandle(summaryResynthesizer, location);
+            if (locationComponents.length == 3 &&
+                locationComponents[0] == 'dart:core' &&
+                locationComponents[1] == 'dart:core' &&
+                locationComponents[2] == 'Never') {
+              element = NeverElementImpl.instance;
+              type = BottomTypeImpl.instance;
+            } else {
+              element = new ClassElementHandle(summaryResynthesizer, location);
+            }
             isDeclarableType = true;
             break;
           case ReferenceKind.constructor:
diff --git a/pkg/analyzer/lib/src/summary/summarize_ast.dart b/pkg/analyzer/lib/src/summary/summarize_ast.dart
@@ -516,7 +516,17 @@ class _SummarizeAstVisitor extends RecursiveAstVisitor {
     b.references = unlinkedReferences;
     b.typedefs = typedefs;
     b.variables = variables;
+
     b.publicNamespace = computePublicNamespace(compilationUnit);
+    if (isCoreLibrary) {
+      b.publicNamespace.names.add(
+        UnlinkedPublicNameBuilder(
+          name: 'Never',
+          kind: ReferenceKind.classOrEnum,
+        ),
+      );
+    }
+
     _computeApiSignature(b);
     return b;
   }
diff --git a/pkg/analyzer/lib/src/summary2/linked_unit_context.dart b/pkg/analyzer/lib/src/summary2/linked_unit_context.dart
@@ -866,7 +866,8 @@ class LinkedUnitContext {
 
     var kind = linkedType.kind;
     if (kind == LinkedNodeTypeKind.bottom) {
-      return BottomTypeImpl.instance;
+      var nullabilitySuffix = _nullabilitySuffix(linkedType.nullabilitySuffix);
+      return BottomTypeImpl.instance.withNullability(nullabilitySuffix);
     } else if (kind == LinkedNodeTypeKind.dynamic_) {
       return DynamicTypeImpl.instance;
     } else if (kind == LinkedNodeTypeKind.function) {
diff --git a/pkg/analyzer/lib/src/summary2/linking_bundle_context.dart b/pkg/analyzer/lib/src/summary2/linking_bundle_context.dart
@@ -80,6 +80,7 @@ class LinkingBundleContext {
     if (type.isBottom) {
       return LinkedNodeTypeBuilder(
         kind: LinkedNodeTypeKind.bottom,
+        nullabilitySuffix: _nullabilitySuffix(type),
       );
     } else if (type.isDynamic) {
       return LinkedNodeTypeBuilder(
diff --git a/pkg/analyzer/lib/src/summary2/named_type_builder.dart b/pkg/analyzer/lib/src/summary2/named_type_builder.dart
@@ -82,6 +82,8 @@ class NamedTypeBuilder extends TypeBuilder {
         var substitution = Substitution.fromPairs(parameters, arguments);
         _type = substitution.substituteType(rawType);
       }
+    } else if (element is NeverElementImpl) {
+      _type = element.type.withNullability(nullabilitySuffix);
     } else if (element is TypeParameterElement) {
       _type = TypeParameterTypeImpl(element);
     } else {
diff --git a/pkg/analyzer/test/src/summary/resynthesize_common.dart b/pkg/analyzer/test/src/summary/resynthesize_common.dart
@@ -9758,6 +9758,28 @@ dynamic v;
 ''');
   }
 
+  test_type_never_disableNnbd() async {
+    featureSet = disableNnbd;
+    var library = await checkLibrary('Never d;');
+    checkElementText(
+        library,
+        r'''
+Never* d;
+''',
+        annotateNullability: true);
+  }
+
+  test_type_never_enableNnbd() async {
+    featureSet = enableNnbd;
+    var library = await checkLibrary('Never d;');
+    checkElementText(
+        library,
+        r'''
+Never d;
+''',
+        annotateNullability: true);
+  }
+
   test_type_param_generic_function_type_nullability_legacy() async {
     featureSet = disableNnbd;
     var library = await checkLibrary('''

Original file line number	Diff line number	Diff line change
`@@ -82,6 +82,8 @@ class NamedTypeBuilder extends TypeBuilder {`
`82`	`82`	`var substitution = Substitution.fromPairs(parameters, arguments);`
`83`	`83`	`_type = substitution.substituteType(rawType);`
`84`	`84`	`}`
	`85`	`+ } else if (element is NeverElementImpl) {`
	`86`	`+ _type = element.type.withNullability(nullabilitySuffix);`
`85`	`87`	`} else if (element is TypeParameterElement) {`
`86`	`88`	`_type = TypeParameterTypeImpl(element);`
`87`	`89`	`} else {`