[cfe] Implement subtype relationship for record types

Part of #49713

Change-Id: I736a4e4f4ba09a80dda1409a1c6640a64ab560f4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/256480
Reviewed-by: Johnni Winther <[email protected]>
Commit-Queue: Chloe Stefantsova <[email protected]>

Author: chloestefantsova

pkg/front_end/messages.status

@@ -217,10 +217,6 @@ DuplicatedNamedArgument/example: Fail
 DuplicatedParameterName/example: Fail
 DuplicatedRecordLiteralFieldName/analyzerCode: Fail
 DuplicatedRecordTypeFieldName/analyzerCode: Fail
-EmptyRecordTypeFieldsList/part_wrapped_script: Crash # Missing subtyping for record types
-EmptyRecordTypeFieldsList/script: Crash # Missing subtyping for record types
-EmptyRecordTypeNamedFieldsList/part_wrapped_script: Crash # Missing subtyping for record types
-EmptyRecordTypeNamedFieldsList/script: Crash # Missing subtyping for record types
 Encoding/analyzerCode: Fail
 EnumAbstractMember/analyzerCode: Fail
 EnumAbstractMember/example: Fail
@@ -752,8 +748,6 @@ NullableTearoffError/analyzerCode: Fail
 NullableTearoffError/example: Fail
 NullableTearoffWarning/analyzerCode: Fail
 NullableTearoffWarning/example: Fail
-OnlyOneRecordTypeFieldsList/part_wrapped_script: Crash # Missing subtyping for record types
-OnlyOneRecordTypeFieldsList/script: Crash # Missing subtyping for record types
 OperatorMinusParameterMismatch/example: Fail
 OperatorParameterMismatch0/analyzerCode: Fail
 OperatorParameterMismatch0/example: Fail

pkg/front_end/messages.yaml

@@ -330,7 +330,7 @@ EmptyRecordTypeFieldsList:
   experiments: records
   script: >
     main() {
-      (/*missing*/) record = (1, 2,);
+      (/*missing*/) record = ((1, 2,) as dynamic);
     }
 
 EmptyRecordTypeNamedFieldsList:
@@ -350,7 +350,7 @@ OnlyOneRecordTypeFieldsList:
   experiments: records
   script: >
     main() {
-      (int /*missing*/) record = (1, 2,);
+      (int /*missing*/) record = ((1, 2,) as dynamic);
     }
 
 DuplicatedRecordTypeFieldName:

pkg/front_end/test/fasta/types/kernel_type_parser_test.dart

@@ -76,6 +76,8 @@ class String extends self::Object {
 }
 class bool extends self::Object {
 }
+class Record extends self::Object {
+}
 class DefaultTypes<S extends self::Object? = dynamic, T extends self::Object, U extends self::List<self::DefaultTypes::S%> = self::List<dynamic>, V extends self::List<self::DefaultTypes::T> = self::List<self::Object>, W extends self::Comparable<self::DefaultTypes::W> = self::Comparable<dynamic>, X extends (self::DefaultTypes::W) → void = (Never) → void, Y extends () → self::DefaultTypes::W = () → self::Comparable<dynamic>> extends self::Object {
 }
 class Super extends self::Object implements self::Comparable<self::Sub> {

pkg/front_end/test/fasta/types/shared_type_tests.dart

@@ -1071,5 +1071,61 @@ abstract class SubtypeTest<T, E> {
     isSubtype("ExtendedClass", "Extension");
     isSubtype("ExtendedGenericClass<num>", "GenericExtension<num>");
     isSubtype("ExtendedSubclass", "Extension");
+
+    // Records.
+    isSubtype("Never", "(int, String)");
+    isSubtype("(int, String)", "Object");
+    isSubtype("(int, String)", "(Object, Object)");
+    isSubtype("(Never, Never)", "(int, String)");
+    isSubtype("(int, String)", "(num, Object)");
+    isSubtype("Never", "(int, {String foo})");
+    isSubtype("(int, {String foo})", "Object");
+    isSubtype("(int, {String foo})", "(Object, {Object foo})");
+    isSubtype("(Never, {Never foo})", "(int, {String foo})");
+    isSubtype("(int, {String foo})", "(num, {Object foo})");
+    isObliviousSubtype("Null", "(int, String)");
+    isNotSubtype("(int, String)", "Null");
+    isNotSubtype("(int, String, bool)", "(int, String)");
+    isNotSubtype("(int, String)", "(int, String, bool)");
+    isNotSubtype("(int, {String foo})", "(int, {String foo, bool bar})");
+    isNotSubtype("(int, {String foo, bool bar})", "(int, {String foo})");
+    isNotSubtype("(int, Never)", "Never");
+    isSubtype("((int, String), bool)", "((num, Object), Object)");
+    isNotSubtype("((int, String), bool)", "(num, (Object, Object))");
+    isSubtype("(int, String)", "Record");
+    isSubtype("(int, {String foo})", "Record");
+    isSubtype("({int foo, String bar})", "Record");
+    isNotSubtype("Record", "(int, String)");
+    isSubtype("Record", "Object");
+    isSubtype("Never", "Record");
+    isObliviousSubtype("Null", "Record");
+    isNotSubtype("(int, String)", "Function");
+    isNotSubtype("Function", "(int, String)");
+    isNotSubtype("(int, String)", "(int, String) -> void");
+    isNotSubtype("(int, String) -> void", "(int, String)");
+    isNotSubtype("(int, String)", "int");
+    isNotSubtype("int", "(int, String)");
+    isSubtype("(int, String)", "FutureOr<(int, String)>");
+    isNotSubtype("FutureOr<(int, String)>", "(int, String)");
+    isSubtype("T", "(int, String)", typeParameters: "T extends (int, String)");
+    isNotSubtype("(int, String)", "T",
+        typeParameters: "T extends (int, String)");
+    isSubtype("T & (int, String)", "(int, String)",
+        typeParameters: "T extends Record");
+    isSubtype("T & (int, String)", "(int, String)",
+        typeParameters: "T extends Object?");
+    isSubtype("T & (int, double)", "(num, num)",
+        typeParameters: "T extends Record");
+    isSubtype("T & (int, double)", "(num, num)",
+        typeParameters: "T extends Object?");
+    isNotSubtype("(int, String)", "T & (int, String)",
+        typeParameters: "T extends Record");
+    isNotSubtype("(int, String)", "T & (int, String)",
+        typeParameters: "T extends Object?");
+    isSubtype("(int, String)", "(int, String)?");
+    isObliviousSubtype("(int, String)?", "(int, String)");
+    isSubtype("Null", "(int, String)?");
+    isObliviousSubtype("Null", "(int, String)");
+    isObliviousSubtype("(int, String)?", "Record");
   }
 }

pkg/kernel/lib/core_types.dart

@@ -134,6 +134,8 @@ class CoreTypes {
 
   late final Class functionClass = index.getClass('dart:core', 'Function');
 
+  late final Class recordClass = index.getClass('dart:core', 'Record');
+
   late final Class futureClass = index.getClass('dart:core', 'Future');
 
   late final Procedure futureSyncFactory =