Store explicitly declared members ahead of inherited members

internal/checker/checker.go

@@ -21351,20 +21351,44 @@ func (c *Checker) getDefaultOrUnknownFromTypeParameter(t *Type) *Type {
 	return core.IfElse(result != nil, result, c.unknownType)
 }
 
-func (c *Checker) getNamedMembers(members ast.SymbolTable) []*ast.Symbol {
+func (c *Checker) getNamedMembers(members ast.SymbolTable, container *ast.Symbol) []*ast.Symbol {
 	if len(members) == 0 {
 		return nil
 	}
+	// For classes and interfaces, we store explicitly declared members ahead of inherited members. This ensures we process
+	// explicitly declared members first in type relations, which is beneficial because explicitly declared members are more
+	// likely to contain discriminating differences. See for example https://github.com/microsoft/typescript-go/issues/1968.
 	result := make([]*ast.Symbol, 0, len(members))
+	var containedCount int
+	if container != nil && container.Flags&(ast.SymbolFlagsClass|ast.SymbolFlagsInterface) != 0 {
+		for id, symbol := range members {
+			if c.isNamedMember(symbol, id) && c.isDeclarationContainedBy(symbol, container) {
+				result = append(result, symbol)
+			}
+		}
+		containedCount = len(result)
+	}
 	for id, symbol := range members {
-		if c.isNamedMember(symbol, id) {
+		if c.isNamedMember(symbol, id) && (container == nil || container.Flags&(ast.SymbolFlagsClass|ast.SymbolFlagsInterface) == 0 || !c.isDeclarationContainedBy(symbol, container)) {
 			result = append(result, symbol)
 		}
 	}
-	c.sortSymbols(result)
+	c.sortSymbols(result[:containedCount])
+	c.sortSymbols(result[containedCount:])
 	return result
 }
 
+func (c *Checker) isDeclarationContainedBy(symbol *ast.Symbol, container *ast.Symbol) bool {
+	if declaration := symbol.ValueDeclaration; declaration != nil {
+		for _, d := range container.Declarations {
+			if declaration.Loc.ContainedBy(d.Loc) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 func (c *Checker) isNamedMember(symbol *ast.Symbol, id string) bool {
 	return !isReservedMemberName(id) && c.symbolIsValue(symbol)
 }
@@ -24338,7 +24362,7 @@ func (c *Checker) setStructuredTypeMembers(t *Type, members ast.SymbolTable, cal
 	t.objectFlags |= ObjectFlagsMembersResolved
 	data := t.AsStructuredType()
 	data.members = members
-	data.properties = c.getNamedMembers(members)
+	data.properties = c.getNamedMembers(members, t.symbol)
 	if len(callSignatures) != 0 {
 		if len(constructSignatures) != 0 {
 			data.signatures = core.Concatenate(callSignatures, constructSignatures)

internal/checker/services.go

@@ -271,7 +271,7 @@ func (c *Checker) getAugmentedPropertiesOfType(t *Type) []*ast.Symbol {
 			}
 		}
 	}
-	return c.getNamedMembers(propsByName)
+	return c.getNamedMembers(propsByName, nil)
 }
 
 func (c *Checker) TryGetMemberInModuleExportsAndProperties(memberName string, moduleSymbol *ast.Symbol) *ast.Symbol {

testdata/baselines/reference/compiler/explicitMembersBeforeInherited.symbols

@@ -0,0 +1,76 @@
+//// [tests/cases/compiler/explicitMembersBeforeInherited.ts] ////
+
+=== explicitMembersBeforeInherited.ts ===
+// https://github.com/microsoft/typescript-go/issues/1968
+
+type IndentationTree<L> = TopNode<L> | VirtualNode<L> | LineNode<L> | BlankNode<L>;
+>IndentationTree : Symbol(IndentationTree, Decl(explicitMembersBeforeInherited.ts, 0, 0))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 2, 21))
+>TopNode : Symbol(TopNode, Decl(explicitMembersBeforeInherited.ts, 11, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 2, 21))
+>VirtualNode : Symbol(VirtualNode, Decl(explicitMembersBeforeInherited.ts, 7, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 2, 21))
+>LineNode : Symbol(LineNode, Decl(explicitMembersBeforeInherited.ts, 15, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 2, 21))
+>BlankNode : Symbol(BlankNode, Decl(explicitMembersBeforeInherited.ts, 19, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 2, 21))
+
+type IndentationSubTree<L> = Exclude<IndentationTree<L>, TopNode<L>>;
+>IndentationSubTree : Symbol(IndentationSubTree, Decl(explicitMembersBeforeInherited.ts, 2, 83))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 3, 24))
+>Exclude : Symbol(Exclude, Decl(lib.es5.d.ts, --, --))
+>IndentationTree : Symbol(IndentationTree, Decl(explicitMembersBeforeInherited.ts, 0, 0))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 3, 24))
+>TopNode : Symbol(TopNode, Decl(explicitMembersBeforeInherited.ts, 11, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 3, 24))
+
+interface NodeBase<L> {
+>NodeBase : Symbol(NodeBase, Decl(explicitMembersBeforeInherited.ts, 3, 69))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 5, 19))
+
+	subs: IndentationSubTree<L>[];
+>subs : Symbol(NodeBase.subs, Decl(explicitMembersBeforeInherited.ts, 5, 23))
+>IndentationSubTree : Symbol(IndentationSubTree, Decl(explicitMembersBeforeInherited.ts, 2, 83))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 5, 19))
+}
+
+interface VirtualNode<L> extends NodeBase<L> {
+>VirtualNode : Symbol(VirtualNode, Decl(explicitMembersBeforeInherited.ts, 7, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 9, 22))
+>NodeBase : Symbol(NodeBase, Decl(explicitMembersBeforeInherited.ts, 3, 69))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 9, 22))
+
+	type: 'virtual';
+>type : Symbol(VirtualNode.type, Decl(explicitMembersBeforeInherited.ts, 9, 46))
+}
+
+interface TopNode<L> extends NodeBase<L> {
+>TopNode : Symbol(TopNode, Decl(explicitMembersBeforeInherited.ts, 11, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 13, 18))
+>NodeBase : Symbol(NodeBase, Decl(explicitMembersBeforeInherited.ts, 3, 69))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 13, 18))
+
+	type: 'top';
+>type : Symbol(TopNode.type, Decl(explicitMembersBeforeInherited.ts, 13, 42))
+}
+
+interface LineNode<L> extends NodeBase<L> {
+>LineNode : Symbol(LineNode, Decl(explicitMembersBeforeInherited.ts, 15, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 17, 19))
+>NodeBase : Symbol(NodeBase, Decl(explicitMembersBeforeInherited.ts, 3, 69))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 17, 19))
+
+	type: 'line';
+>type : Symbol(LineNode.type, Decl(explicitMembersBeforeInherited.ts, 17, 43))
+}
+
+interface BlankNode<L> extends NodeBase<L> {
+>BlankNode : Symbol(BlankNode, Decl(explicitMembersBeforeInherited.ts, 19, 1))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 21, 20))
+>NodeBase : Symbol(NodeBase, Decl(explicitMembersBeforeInherited.ts, 3, 69))
+>L : Symbol(L, Decl(explicitMembersBeforeInherited.ts, 21, 20))
+
+	type: 'blank';
+>type : Symbol(BlankNode.type, Decl(explicitMembersBeforeInherited.ts, 21, 44))
+}
+

testdata/baselines/reference/compiler/explicitMembersBeforeInherited.types

@@ -0,0 +1,36 @@
+//// [tests/cases/compiler/explicitMembersBeforeInherited.ts] ////
+
+=== explicitMembersBeforeInherited.ts ===
+// https://github.com/microsoft/typescript-go/issues/1968
+
+type IndentationTree<L> = TopNode<L> | VirtualNode<L> | LineNode<L> | BlankNode<L>;
+>IndentationTree : IndentationTree<L>
+
+type IndentationSubTree<L> = Exclude<IndentationTree<L>, TopNode<L>>;
+>IndentationSubTree : IndentationSubTree<L>
+
+interface NodeBase<L> {
+	subs: IndentationSubTree<L>[];
+>subs : IndentationSubTree<L>[]
+}
+
+interface VirtualNode<L> extends NodeBase<L> {
+	type: 'virtual';
+>type : "virtual"
+}
+
+interface TopNode<L> extends NodeBase<L> {
+	type: 'top';
+>type : "top"
+}
+
+interface LineNode<L> extends NodeBase<L> {
+	type: 'line';
+>type : "line"
+}
+
+interface BlankNode<L> extends NodeBase<L> {
+	type: 'blank';
+>type : "blank"
+}
+

testdata/baselines/reference/submodule/compiler/arrayAssignmentTest1.errors.txt

@@ -1,6 +1,6 @@
 arrayAssignmentTest1.ts(46,5): error TS2741: Property 'IM1' is missing in type 'undefined[]' but required in type 'I1'.
 arrayAssignmentTest1.ts(47,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C1': IM1, C1M1
-arrayAssignmentTest1.ts(48,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': IM1, C1M1, C2M1
+arrayAssignmentTest1.ts(48,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': C2M1, IM1, C1M1
 arrayAssignmentTest1.ts(49,5): error TS2741: Property 'CM3M1' is missing in type 'undefined[]' but required in type 'C3'.
 arrayAssignmentTest1.ts(60,1): error TS2322: Type 'C3[]' is not assignable to type 'I1[]'.
   Property 'IM1' is missing in type 'C3' but required in type 'I1'.
@@ -11,9 +11,9 @@ arrayAssignmentTest1.ts(65,1): error TS2322: Type 'C3[]' is not assignable to ty
 arrayAssignmentTest1.ts(68,1): error TS2322: Type 'C1[]' is not assignable to type 'C2[]'.
   Property 'C2M1' is missing in type 'C1' but required in type 'C2'.
 arrayAssignmentTest1.ts(69,1): error TS2322: Type 'I1[]' is not assignable to type 'C2[]'.
-  Type 'I1' is missing the following properties from type 'C2': C1M1, C2M1
+  Type 'I1' is missing the following properties from type 'C2': C2M1, C1M1
 arrayAssignmentTest1.ts(70,1): error TS2322: Type 'C3[]' is not assignable to type 'C2[]'.
-  Type 'C3' is missing the following properties from type 'C2': IM1, C1M1, C2M1
+  Type 'C3' is missing the following properties from type 'C2': C2M1, IM1, C1M1
 arrayAssignmentTest1.ts(75,1): error TS2322: Type 'C2[]' is not assignable to type 'C3[]'.
   Property 'CM3M1' is missing in type 'C2' but required in type 'C3'.
 arrayAssignmentTest1.ts(76,1): error TS2322: Type 'C1[]' is not assignable to type 'C3[]'.
@@ -83,7 +83,7 @@ arrayAssignmentTest1.ts(85,1): error TS2740: Type 'I1' is missing the following
 !!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C1': IM1, C1M1
     var c2_error: C2 = []; // should be an error - is
         ~~~~~~~~
-!!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': IM1, C1M1, C2M1
+!!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': C2M1, IM1, C1M1
     var c3_error: C3 = []; // should be an error - is
         ~~~~~~~~
 !!! error TS2741: Property 'CM3M1' is missing in type 'undefined[]' but required in type 'C3'.
@@ -125,11 +125,11 @@ arrayAssignmentTest1.ts(85,1): error TS2740: Type 'I1' is missing the following
     arr_c2 = arr_i1; // should be an error - subtype relationship - is
     ~~~~~~
 !!! error TS2322: Type 'I1[]' is not assignable to type 'C2[]'.
-!!! error TS2322:   Type 'I1' is missing the following properties from type 'C2': C1M1, C2M1
+!!! error TS2322:   Type 'I1' is missing the following properties from type 'C2': C2M1, C1M1
     arr_c2 = arr_c3; // should be an error - is
     ~~~~~~
 !!! error TS2322: Type 'C3[]' is not assignable to type 'C2[]'.
-!!! error TS2322:   Type 'C3' is missing the following properties from type 'C2': IM1, C1M1, C2M1
+!!! error TS2322:   Type 'C3' is missing the following properties from type 'C2': C2M1, IM1, C1M1
 
     // "clean up bug" occurs at this point
     // if you move these three expressions to another file, they raise an error

testdata/baselines/reference/submodule/compiler/arrayAssignmentTest1.errors.txt.diff

@@ -0,0 +1,45 @@
+--- old.arrayAssignmentTest1.errors.txt
++++ new.arrayAssignmentTest1.errors.txt
+@@= skipped -0, +0 lines =@@
+ arrayAssignmentTest1.ts(46,5): error TS2741: Property 'IM1' is missing in type 'undefined[]' but required in type 'I1'.
+ arrayAssignmentTest1.ts(47,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C1': IM1, C1M1
+-arrayAssignmentTest1.ts(48,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': IM1, C1M1, C2M1
++arrayAssignmentTest1.ts(48,5): error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': C2M1, IM1, C1M1
+ arrayAssignmentTest1.ts(49,5): error TS2741: Property 'CM3M1' is missing in type 'undefined[]' but required in type 'C3'.
+ arrayAssignmentTest1.ts(60,1): error TS2322: Type 'C3[]' is not assignable to type 'I1[]'.
+   Property 'IM1' is missing in type 'C3' but required in type 'I1'.
+@@= skipped -10, +10 lines =@@
+ arrayAssignmentTest1.ts(68,1): error TS2322: Type 'C1[]' is not assignable to type 'C2[]'.
+   Property 'C2M1' is missing in type 'C1' but required in type 'C2'.
+ arrayAssignmentTest1.ts(69,1): error TS2322: Type 'I1[]' is not assignable to type 'C2[]'.
+-  Type 'I1' is missing the following properties from type 'C2': C1M1, C2M1
++  Type 'I1' is missing the following properties from type 'C2': C2M1, C1M1
+ arrayAssignmentTest1.ts(70,1): error TS2322: Type 'C3[]' is not assignable to type 'C2[]'.
+-  Type 'C3' is missing the following properties from type 'C2': IM1, C1M1, C2M1
++  Type 'C3' is missing the following properties from type 'C2': C2M1, IM1, C1M1
+ arrayAssignmentTest1.ts(75,1): error TS2322: Type 'C2[]' is not assignable to type 'C3[]'.
+   Property 'CM3M1' is missing in type 'C2' but required in type 'C3'.
+ arrayAssignmentTest1.ts(76,1): error TS2322: Type 'C1[]' is not assignable to type 'C3[]'.
+@@= skipped -72, +72 lines =@@
+ !!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C1': IM1, C1M1
+     var c2_error: C2 = []; // should be an error - is
+         ~~~~~~~~
+-!!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': IM1, C1M1, C2M1
++!!! error TS2739: Type 'undefined[]' is missing the following properties from type 'C2': C2M1, IM1, C1M1
+     var c3_error: C3 = []; // should be an error - is
+         ~~~~~~~~
+ !!! error TS2741: Property 'CM3M1' is missing in type 'undefined[]' but required in type 'C3'.
+@@= skipped -42, +42 lines =@@
+     arr_c2 = arr_i1; // should be an error - subtype relationship - is
+     ~~~~~~
+ !!! error TS2322: Type 'I1[]' is not assignable to type 'C2[]'.
+-!!! error TS2322:   Type 'I1' is missing the following properties from type 'C2': C1M1, C2M1
++!!! error TS2322:   Type 'I1' is missing the following properties from type 'C2': C2M1, C1M1
+     arr_c2 = arr_c3; // should be an error - is
+     ~~~~~~
+ !!! error TS2322: Type 'C3[]' is not assignable to type 'C2[]'.
+-!!! error TS2322:   Type 'C3' is missing the following properties from type 'C2': IM1, C1M1, C2M1
++!!! error TS2322:   Type 'C3' is missing the following properties from type 'C2': C2M1, IM1, C1M1
+
+     // "clean up bug" occurs at this point
+     // if you move these three expressions to another file, they raise an error

testdata/baselines/reference/submodule/compiler/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.errors.txt

@@ -1,5 +1,5 @@
 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,64): error TS2741: Property 'z' is missing in type 'B' but required in type 'C'.
-chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,81): error TS2739: Type 'A' is missing the following properties from type 'C': y, z
+chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,81): error TS2739: Type 'A' is missing the following properties from type 'C': z, y
 
 
 ==== chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts (2 errors) ====
@@ -27,5 +27,5 @@ chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,81): error TS
 !!! related TS2728 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:15:5: 'z' is declared here.
 !!! related TS6502 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:3:27: The expected type comes from the return type of this signature.
                                                                                     ~~~~~
-!!! error TS2739: Type 'A' is missing the following properties from type 'C': y, z
+!!! error TS2739: Type 'A' is missing the following properties from type 'C': z, y
 !!! related TS6502 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:3:27: The expected type comes from the return type of this signature.

testdata/baselines/reference/submodule/compiler/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.errors.txt.diff

@@ -0,0 +1,16 @@
+--- old.chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.errors.txt
++++ new.chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.errors.txt
+@@= skipped -0, +0 lines =@@
+ chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,64): error TS2741: Property 'z' is missing in type 'B' but required in type 'C'.
+-chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,81): error TS2739: Type 'A' is missing the following properties from type 'C': y, z
++chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts(19,81): error TS2739: Type 'A' is missing the following properties from type 'C': z, y
+
+
+ ==== chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts (2 errors) ====
+@@= skipped -26, +26 lines =@@
+ !!! related TS2728 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:15:5: 'z' is declared here.
+ !!! related TS6502 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:3:27: The expected type comes from the return type of this signature.
+                                                                                     ~~~~~
+-!!! error TS2739: Type 'A' is missing the following properties from type 'C': y, z
++!!! error TS2739: Type 'A' is missing the following properties from type 'C': z, y
+ !!! related TS6502 chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.ts:3:27: The expected type comes from the return type of this signature.

testdata/baselines/reference/submodule/compiler/emitClassExpressionInDeclarationFile.js

@@ -90,17 +90,17 @@ export declare class FooItem {
 export type Constructor<T> = new (...args: any[]) => T;
 export declare function WithTags<T extends Constructor<FooItem>>(Base: T): {
     new (...args: any[]): {
+        tags(): void;
         foo(): void;
         name?: string;
-        tags(): void;
     };
     getTags(): void;
 } & T;
 declare const Test_base: {
     new (...args: any[]): {
+        tags(): void;
         foo(): void;
         name?: string;
-        tags(): void;
     };
     getTags(): void;
 } & typeof FooItem;

testdata/baselines/reference/submodule/compiler/emitClassExpressionInDeclarationFile.js.diff

@@ -25,4 +25,24 @@
 +        tags(c: any): any;
      };
  };
- export declare class FooItem {
+ export declare class FooItem {
+@@= skipped -10, +10 lines =@@
+ export type Constructor<T> = new (...args: any[]) => T;
+ export declare function WithTags<T extends Constructor<FooItem>>(Base: T): {
+     new (...args: any[]): {
++        tags(): void;
+         foo(): void;
+         name?: string;
+-        tags(): void;
+     };
+     getTags(): void;
+ } & T;
+ declare const Test_base: {
+     new (...args: any[]): {
++        tags(): void;
+         foo(): void;
+         name?: string;
+-        tags(): void;
+     };
+     getTags(): void;
+ } & typeof FooItem;

testdata/baselines/reference/submodule/compiler/emitClassExpressionInDeclarationFile2.js

@@ -83,19 +83,19 @@ export declare class FooItem {
 export type Constructor<T> = new (...args: any[]) => T;
 export declare function WithTags<T extends Constructor<FooItem>>(Base: T): {
     new (...args: any[]): {
+        tags(): void;
         foo(): void;
         name?: string;
         property: string;
-        tags(): void;
     };
     getTags(): void;
 } & T;
 declare const Test_base: {
     new (...args: any[]): {
+        tags(): void;
         foo(): void;
         name?: string;
         property: string;
-        tags(): void;
     };
     getTags(): void;
 } & typeof FooItem;

testdata/baselines/reference/submodule/compiler/emitClassExpressionInDeclarationFile2.js.diff

@@ -65,19 +65,19 @@
 +export type Constructor<T> = new (...args: any[]) => T;
 +export declare function WithTags<T extends Constructor<FooItem>>(Base: T): {
 +    new (...args: any[]): {
++        tags(): void;
 +        foo(): void;
 +        name?: string;
 +        property: string;
-+        tags(): void;
 +    };
 +    getTags(): void;
 +} & T;
 +declare const Test_base: {
 +    new (...args: any[]): {
++        tags(): void;
 +        foo(): void;
 +        name?: string;
 +        property: string;
-+        tags(): void;
 +    };
 +    getTags(): void;
 +} & typeof FooItem;