Merge pull request #31521 from microsoft/relatedSpanSubsequentDeclarations

Related error spans on disagreeing declarations

Author: DanielRosenwasser

src/compiler/checker.ts

@@ -5352,7 +5352,7 @@ namespace ts {
                     return type;
                 }
                 else if (declaredType !== errorType && type !== errorType && !isTypeIdenticalTo(declaredType, type)) {
-                    errorNextVariableOrPropertyDeclarationMustHaveSameType(declaredType, declaration, type);
+                    errorNextVariableOrPropertyDeclarationMustHaveSameType(/*firstDeclaration*/ undefined, declaredType, declaration, type);
                 }
             }
             return declaredType;
@@ -26839,7 +26839,7 @@ namespace ts {
                 if (type !== errorType && declarationType !== errorType &&
                     !isTypeIdenticalTo(type, declarationType) &&
                     !(symbol.flags & SymbolFlags.Assignment)) {
-                    errorNextVariableOrPropertyDeclarationMustHaveSameType(type, node, declarationType);
+                    errorNextVariableOrPropertyDeclarationMustHaveSameType(symbol.valueDeclaration, type, node, declarationType);
                 }
                 if (node.initializer) {
                     checkTypeAssignableToAndOptionallyElaborate(checkExpressionCached(node.initializer), declarationType, node, node.initializer, /*headMessage*/ undefined);
@@ -26859,17 +26859,24 @@ namespace ts {
             }
         }
 
-        function errorNextVariableOrPropertyDeclarationMustHaveSameType(firstType: Type, nextDeclaration: Declaration, nextType: Type): void {
+        function errorNextVariableOrPropertyDeclarationMustHaveSameType(firstDeclaration: Declaration | undefined, firstType: Type, nextDeclaration: Declaration, nextType: Type): void {
             const nextDeclarationName = getNameOfDeclaration(nextDeclaration);
             const message = nextDeclaration.kind === SyntaxKind.PropertyDeclaration || nextDeclaration.kind === SyntaxKind.PropertySignature
                 ? Diagnostics.Subsequent_property_declarations_must_have_the_same_type_Property_0_must_be_of_type_1_but_here_has_type_2
                 : Diagnostics.Subsequent_variable_declarations_must_have_the_same_type_Variable_0_must_be_of_type_1_but_here_has_type_2;
-            error(
+            const declName = declarationNameToString(nextDeclarationName);
+            const err = error(
                 nextDeclarationName,
                 message,
-                declarationNameToString(nextDeclarationName),
+                declName,
                 typeToString(firstType),
-                typeToString(nextType));
+                typeToString(nextType)
+            );
+            if (firstDeclaration) {
+                addRelatedInfo(err,
+                    createDiagnosticForNode(firstDeclaration, Diagnostics._0_was_also_declared_here, declName)
+                );
+            }
         }
 
         function areDeclarationFlagsIdentical(left: Declaration, right: Declaration) {

tests/baselines/reference/ES5For-of7.errors.txt

@@ -10,4 +10,5 @@ tests/cases/conformance/statements/for-ofStatements/ES5For-of7.ts(6,9): error TS
         var x = [w, v];
             ~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'any', but here has type 'any[]'.
+!!! related TS6203 tests/cases/conformance/statements/for-ofStatements/ES5For-of7.ts:2:9: 'x' was also declared here.
     }

tests/baselines/reference/FunctionAndModuleWithSameNameAndCommonRoot.errors.txt

@@ -24,6 +24,7 @@ tests/cases/conformance/internalModules/DeclarationMerging/test.ts(2,5): error T
     var fn = A.Point;
         ~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'fn' must be of type '() => { x: number; y: number; }', but here has type 'typeof Point'.
+!!! related TS6203 tests/cases/conformance/internalModules/DeclarationMerging/test.ts:1:5: 'fn' was also declared here.
 
     var cl: { x: number; y: number; }
     var cl = A.Point();
@@ -46,6 +47,7 @@ tests/cases/conformance/internalModules/DeclarationMerging/test.ts(2,5): error T
     var fn = B.Point;  // not expected to be an error. bug 840000: [corelang] Function of fundule not assignalbe as expected
         ~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'fn' must be of type '() => { x: number; y: number; }', but here has type 'typeof Point'.
+!!! related TS6203 tests/cases/conformance/internalModules/DeclarationMerging/test.ts:1:5: 'fn' was also declared here.
 
     var cl: { x: number; y: number; }
     var cl = B.Point();

tests/baselines/reference/asyncArrowFunction5_es2017.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es2017/asyncArrowFunction/asyncArrowFunction5_es20
 !!! error TS1005: ',' expected.
                              ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                     ~
 !!! error TS1005: ',' expected.
                                            ~~

tests/baselines/reference/asyncArrowFunction5_es5.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es5/asyncArrowFunction/asyncArrowFunction5_es5.ts(
 !!! error TS1005: ',' expected.
                              ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                     ~
 !!! error TS1005: ',' expected.
                                            ~~

tests/baselines/reference/asyncArrowFunction5_es6.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es6/asyncArrowFunction/asyncArrowFunction5_es6.ts(
 !!! error TS1005: ',' expected.
                              ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                     ~
 !!! error TS1005: ',' expected.
                                            ~~

tests/baselines/reference/asyncArrowFunction9_es2017.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es2017/asyncArrowFunction/asyncArrowFunction9_es20
 !!! error TS1005: ',' expected.
                                           ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                                  ~
 !!! error TS1005: ',' expected.
                                                         ~~

tests/baselines/reference/asyncArrowFunction9_es5.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es5/asyncArrowFunction/asyncArrowFunction9_es5.ts(
 !!! error TS1005: ',' expected.
                                           ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                                  ~
 !!! error TS1005: ',' expected.
                                                         ~~

tests/baselines/reference/asyncArrowFunction9_es6.errors.txt

@@ -16,6 +16,7 @@ tests/cases/conformance/async/es6/asyncArrowFunction/asyncArrowFunction9_es6.ts(
 !!! error TS1005: ',' expected.
                                           ~~~~~~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'Promise' must be of type 'PromiseConstructor', but here has type 'any'.
+!!! related TS6203 /.ts/lib.es2015.promise.d.ts:152:13: 'Promise' was also declared here.
                                                  ~
 !!! error TS1005: ',' expected.
                                                         ~~

tests/baselines/reference/augmentedTypesVar.errors.txt

@@ -30,6 +30,7 @@ tests/cases/compiler/augmentedTypesVar.ts(31,8): error TS2300: Duplicate identif
     var x3 = () => { } // error
         ~~
 !!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x3' must be of type 'number', but here has type '() => void'.
+!!! related TS6203 tests/cases/compiler/augmentedTypesVar.ts:9:5: 'x3' was also declared here.
 
     // var then class
     var x4 = 1; // error