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Merged
merged 3 commits into from
Jul 2, 2018
Merged

Related error spans on "used before declared" error messages #25359

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4459730
Give related error on declaration location for used-before-declared e…
DanielRosenwasser Jul 2, 2018
c4500bd
Addressed code review feedback.
DanielRosenwasser Jul 2, 2018
f675798
Accepted baselines.
DanielRosenwasser Jul 2, 2018
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33 changes: 26 additions & 7 deletions src/compiler/checker.ts
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Expand Up @@ -1655,14 +1655,25 @@ namespace ts {
if (declaration === undefined) return Debug.fail("Declaration to checkResolvedBlockScopedVariable is undefined");

if (!(declaration.flags & NodeFlags.Ambient) && !isBlockScopedNameDeclaredBeforeUse(declaration, errorLocation)) {
let diagnosticMessage;
const declarationName = declarationNameToString(getNameOfDeclaration(declaration));
if (result.flags & SymbolFlags.BlockScopedVariable) {
error(errorLocation, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, declarationNameToString(getNameOfDeclaration(declaration)));
diagnosticMessage = error(errorLocation, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, declarationName);
}
else if (result.flags & SymbolFlags.Class) {
error(errorLocation, Diagnostics.Class_0_used_before_its_declaration, declarationNameToString(getNameOfDeclaration(declaration)));
diagnosticMessage = error(errorLocation, Diagnostics.Class_0_used_before_its_declaration, declarationName);
}
else if (result.flags & SymbolFlags.RegularEnum) {
error(errorLocation, Diagnostics.Enum_0_used_before_its_declaration, declarationNameToString(getNameOfDeclaration(declaration)));
diagnosticMessage = error(errorLocation, Diagnostics.Enum_0_used_before_its_declaration, declarationName);
}
else {
Debug.assert(!!(result.flags & SymbolFlags.ConstEnum));
}

if (diagnosticMessage) {
addRelatedInfo(diagnosticMessage,
createDiagnosticForNode(declaration, Diagnostics._0_was_declared_here, declarationName)
);
}
}
}
Expand Down Expand Up @@ -17460,16 +17471,24 @@ namespace ts {
return;
}

let diagnosticMessage;
const declarationName = idText(right);
if (isInPropertyInitializer(node) &&
!isBlockScopedNameDeclaredBeforeUse(valueDeclaration, right)
&& !isPropertyDeclaredInAncestorClass(prop)) {
error(right, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, idText(right));
diagnosticMessage = error(right, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, declarationName);
}
else if (valueDeclaration.kind === SyntaxKind.ClassDeclaration &&
node.parent.kind !== SyntaxKind.TypeReference &&
!(valueDeclaration.flags & NodeFlags.Ambient) &&
!isBlockScopedNameDeclaredBeforeUse(valueDeclaration, right)) {
error(right, Diagnostics.Class_0_used_before_its_declaration, idText(right));
diagnosticMessage = error(right, Diagnostics.Class_0_used_before_its_declaration, declarationName);
}

if (diagnosticMessage) {
addRelatedInfo(diagnosticMessage,
createDiagnosticForNode(valueDeclaration, Diagnostics._0_was_declared_here, declarationName)
);
}
}

Expand Down Expand Up @@ -19083,8 +19102,8 @@ namespace ts {
if (importNode && !isImportCall(importNode)) {
const sigs = getSignaturesOfType(getTypeOfSymbol(getSymbolLinks(apparentType.symbol).target!), kind);
if (!sigs || !sigs.length) return;
diagnostic.relatedInformation = diagnostic.relatedInformation || [];
diagnostic.relatedInformation.push(createDiagnosticForNode(importNode, Diagnostics.Type_originates_at_this_import_A_namespace_style_import_cannot_be_called_or_constructed_and_will_cause_a_failure_at_runtime_Consider_using_a_default_import_or_import_require_here_instead));
Debug.assert(!diagnostic.relatedInformation);
diagnostic.relatedInformation = [createDiagnosticForNode(importNode, Diagnostics.Type_originates_at_this_import_A_namespace_style_import_cannot_be_called_or_constructed_and_will_cause_a_failure_at_runtime_Consider_using_a_default_import_or_import_require_here_instead)];
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@weswigham weswigham Jul 2, 2018 •
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If we're going to update this, we should probably just update it to use addRelatedInfo. This can actually potentially stack with the related info provided by #25140, after all, since they're for the same (assignability) diagnostics.

}
}

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4 changes: 4 additions & 0 deletions src/compiler/diagnosticMessages.json
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Expand Up @@ -2397,6 +2397,10 @@
"category": "Error",
"code": 2727
},
"'{0}' was declared here.": {
"category": "Error",
"code": 2728
},

"Import declaration '{0}' is using private name '{1}'.": {
"category": "Error",
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/ES5For-of17.errors.txt
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Expand Up @@ -7,6 +7,7 @@ tests/cases/conformance/statements/for-ofStatements/ES5For-of17.ts(3,20): error
for (let v of [v]) {
~
!!! error TS2448: Block-scoped variable 'v' used before its declaration.
!!! related TS2728 tests/cases/conformance/statements/for-ofStatements/ES5For-of17.ts:3:14: 'v' was declared here.
var x = v;
v++;
}
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/ES5For-of20.errors.txt
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Expand Up @@ -8,6 +8,7 @@ tests/cases/conformance/statements/for-ofStatements/ES5For-of20.ts(4,15): error
for (let v of [v]) {
~
!!! error TS2448: Block-scoped variable 'v' used before its declaration.
!!! related TS2728 tests/cases/conformance/statements/for-ofStatements/ES5For-of20.ts:3:14: 'v' was declared here.
const v;
~
!!! error TS1155: 'const' declarations must be initialized.
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/ModuleAndClassWithSameNameAndCommonRoot.errors.txt
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Expand Up @@ -32,6 +32,7 @@ tests/cases/conformance/internalModules/DeclarationMerging/simple.ts(2,31): erro
export var Instance = new A();
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/conformance/internalModules/DeclarationMerging/simple.ts:6:7: 'A' was declared here.
}

// duplicate identifier
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/api/tsserverlibrary.d.ts
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Expand Up @@ -5418,6 +5418,7 @@ declare namespace ts {
Class_name_cannot_be_Object_when_targeting_ES5_with_module_0: DiagnosticMessage;
Cannot_find_lib_definition_for_0: DiagnosticMessage;
Cannot_find_lib_definition_for_0_Did_you_mean_1: DiagnosticMessage;
_0_was_declared_here: DiagnosticMessage;
Import_declaration_0_is_using_private_name_1: DiagnosticMessage;
Type_parameter_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
Type_parameter_0_of_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
Expand Down
5 changes: 4 additions & 1 deletion tests/baselines/reference/blockScopedBindingUsedBeforeDef.errors.txt
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Expand Up @@ -8,13 +8,16 @@ tests/cases/compiler/blockScopedBindingUsedBeforeDef.ts(8,7): error TS2448: Bloc
for (let {[a]: a} of [{ }]) continue;
~
!!! error TS2448: Block-scoped variable 'a' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedBindingUsedBeforeDef.ts:2:16: 'a' was declared here.

// 2:
for (let {[a]: a} = { }; false; ) continue;
~
!!! error TS2448: Block-scoped variable 'a' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedBindingUsedBeforeDef.ts:5:16: 'a' was declared here.

// 3:
let {[b]: b} = { };
~
!!! error TS2448: Block-scoped variable 'b' used before its declaration.
!!! error TS2448: Block-scoped variable 'b' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedBindingUsedBeforeDef.ts:8:11: 'b' was declared here.
4 changes: 4 additions & 0 deletions tests/baselines/reference/blockScopedVariablesUseBeforeDef.errors.txt
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Expand Up @@ -9,6 +9,7 @@ tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts(100,12): error TS2448:
let a = x;
~
!!! error TS2448: Block-scoped variable 'x' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts:3:9: 'x' was declared here.
let x;
}

Expand Down Expand Up @@ -67,6 +68,7 @@ tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts(100,12): error TS2448:
static a = x;
~
!!! error TS2448: Block-scoped variable 'x' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts:60:9: 'x' was declared here.
}
let x;
}
Expand All @@ -76,6 +78,7 @@ tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts(100,12): error TS2448:
static a = x;
~
!!! error TS2448: Block-scoped variable 'x' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts:67:9: 'x' was declared here.
}
let x;
}
Expand Down Expand Up @@ -113,6 +116,7 @@ tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts(100,12): error TS2448:
a: x
~
!!! error TS2448: Block-scoped variable 'x' used before its declaration.
!!! related TS2728 tests/cases/compiler/blockScopedVariablesUseBeforeDef.ts:102:9: 'x' was declared here.
}
let x
}
1 change: 1 addition & 0 deletions tests/baselines/reference/circularImportAlias.errors.txt
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Expand Up @@ -9,6 +9,7 @@ tests/cases/conformance/internalModules/importDeclarations/circularImportAlias.t
export class D extends a.C {
~
!!! error TS2449: Class 'C' used before its declaration.
!!! related TS2728 tests/cases/conformance/internalModules/importDeclarations/circularImportAlias.ts:11:18: 'C' was declared here.
id: number;
}
}
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/classAbstractInstantiations2.errors.txt
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Expand Up @@ -45,6 +45,7 @@ tests/cases/conformance/classes/classDeclarations/classAbstractKeyword/classAbst
var x : any = C;
~
!!! error TS2449: Class 'C' used before its declaration.
!!! related TS2728 tests/cases/conformance/classes/classDeclarations/classAbstractKeyword/classAbstractInstantiations2.ts:26:7: 'C' was declared here.
new x; // okay -- undefined behavior at runtime

class C extends B { } // error -- not declared abstract
Expand Down
4 changes: 4 additions & 0 deletions tests/baselines/reference/classDeclarationShouldBeOutOfScopeInComputedNames.errors.txt
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Expand Up @@ -12,14 +12,18 @@ tests/cases/compiler/classDeclarationShouldBeOutOfScopeInComputedNames.ts(8,6):
static readonly [A.p1] = 0;
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classDeclarationShouldBeOutOfScopeInComputedNames.ts:1:7: 'A' was declared here.
static [A.p2]() { return 0 };
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classDeclarationShouldBeOutOfScopeInComputedNames.ts:1:7: 'A' was declared here.
[A.p1]() { }
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classDeclarationShouldBeOutOfScopeInComputedNames.ts:1:7: 'A' was declared here.
[A.p2] = 0
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classDeclarationShouldBeOutOfScopeInComputedNames.ts:1:7: 'A' was declared here.
}

2 changes: 2 additions & 0 deletions tests/baselines/reference/classExtendsItselfIndirectly.errors.txt
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Expand Up @@ -14,6 +14,7 @@ tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/cla
!!! error TS2506: 'C' is referenced directly or indirectly in its own base expression.
~
!!! error TS2449: Class 'E' used before its declaration.
!!! related TS2728 tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/classExtendsItselfIndirectly.ts:5:7: 'E' was declared here.

class D extends C { bar: string; }
~
Expand All @@ -28,6 +29,7 @@ tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/cla
!!! error TS2506: 'C2' is referenced directly or indirectly in its own base expression.
~~
!!! error TS2449: Class 'E2' used before its declaration.
!!! related TS2728 tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/classExtendsItselfIndirectly.ts:11:7: 'E2' was declared here.

class D2<T> extends C2<T> { bar: T; }
~~
Expand Down
2 changes: 2 additions & 0 deletions tests/baselines/reference/classExtendsItselfIndirectly2.errors.txt
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Expand Up @@ -14,6 +14,7 @@ tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/cla
!!! error TS2506: 'C' is referenced directly or indirectly in its own base expression.
~
!!! error TS2449: Class 'E' used before its declaration.
!!! related TS2728 tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/classExtendsItselfIndirectly2.ts:9:18: 'E' was declared here.

module M {
export class D extends C { bar: string; }
Expand All @@ -34,6 +35,7 @@ tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/cla
!!! error TS2506: 'C2' is referenced directly or indirectly in its own base expression.
~~
!!! error TS2449: Class 'E2' used before its declaration.
!!! related TS2728 tests/cases/conformance/classes/classDeclarations/classHeritageSpecification/classExtendsItselfIndirectly2.ts:20:22: 'E2' was declared here.

module P {
export class D2<T> extends C2<T> { bar: T; }
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/classInheritence.errors.txt
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Expand Up @@ -6,6 +6,7 @@ tests/cases/compiler/classInheritence.ts(2,7): error TS2506: 'A' is referenced d
class B extends A { }
~
!!! error TS2449: Class 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classInheritence.ts:2:7: 'A' was declared here.
class A extends A { }
~
!!! error TS2506: 'A' is referenced directly or indirectly in its own base expression.
1 change: 1 addition & 0 deletions tests/baselines/reference/classMergedWithInterfaceMultipleBasesNoError.errors.txt
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Expand Up @@ -12,5 +12,6 @@ tests/cases/compiler/classMergedWithInterfaceMultipleBasesNoError.ts(8,30): erro
readonly observer = this.handleIntersection;
~~~~~~~~~~~~~~~~~~
!!! error TS2448: Block-scoped variable 'handleIntersection' used before its declaration.
!!! related TS2728 tests/cases/compiler/classMergedWithInterfaceMultipleBasesNoError.ts:9:14: 'handleIntersection' was declared here.
readonly handleIntersection = () => { }
}
1 change: 1 addition & 0 deletions tests/baselines/reference/classOrder2.errors.txt
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Expand Up @@ -5,6 +5,7 @@ tests/cases/compiler/classOrder2.ts(1,17): error TS2449: Class 'B' used before i
class A extends B {
~
!!! error TS2449: Class 'B' used before its declaration.
!!! related TS2728 tests/cases/compiler/classOrder2.ts:7:7: 'B' was declared here.

foo() { this.bar(); }

Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/classSideInheritance2.errors.txt
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Expand Up @@ -11,6 +11,7 @@ tests/cases/compiler/classSideInheritance2.ts(7,23): error TS2449: Class 'TextBa
class SubText extends TextBase {
~~~~~~~~
!!! error TS2449: Class 'TextBase' used before its declaration.
!!! related TS2728 tests/cases/compiler/classSideInheritance2.ts:14:7: 'TextBase' was declared here.

constructor(text: IText, span: TextSpan) {
super();
Expand Down
5 changes: 5 additions & 0 deletions tests/baselines/reference/classStaticInitializersUsePropertiesBeforeDeclaration.errors.txt
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Expand Up @@ -10,16 +10,21 @@ tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts(4,
static enumMember = Enum.A;
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts:7:6: 'Enum' was declared here.
~
!!! error TS2448: Block-scoped variable 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts:8:5: 'A' was declared here.
static objLiteralMember = ObjLiteral.A;
~~~~~~~~~~
!!! error TS2448: Block-scoped variable 'ObjLiteral' used before its declaration.
!!! related TS2728 tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts:11:7: 'ObjLiteral' was declared here.
~
!!! error TS2448: Block-scoped variable 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts:12:5: 'A' was declared here.
static namespaceMember = Namespace.A;
~
!!! error TS2448: Block-scoped variable 'A' used before its declaration.
!!! related TS2728 tests/cases/compiler/classStaticInitializersUsePropertiesBeforeDeclaration.ts:16:16: 'A' was declared here.
}

enum Enum {
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/complexClassRelationships.errors.txt
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Expand Up @@ -6,6 +6,7 @@ tests/cases/compiler/complexClassRelationships.ts(2,23): error TS2449: Class 'Ba
class Derived extends Base {
~~~~
!!! error TS2449: Class 'Base' used before its declaration.
!!! related TS2728 tests/cases/compiler/complexClassRelationships.ts:13:7: 'Base' was declared here.
public static createEmpty(): Derived {
var item = new Derived();
return item;
Expand Down
3 changes: 3 additions & 0 deletions tests/baselines/reference/computedPropertyNamesWithStaticProperty.errors.txt
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Expand Up @@ -9,14 +9,17 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesWithStaticPr
get [C.staticProp]() {
~
!!! error TS2449: Class 'C' used before its declaration.
!!! related TS2728 tests/cases/conformance/es6/computedProperties/computedPropertyNamesWithStaticProperty.ts:1:7: 'C' was declared here.
return "hello";
}
set [C.staticProp](x: string) {
~
!!! error TS2449: Class 'C' used before its declaration.
!!! related TS2728 tests/cases/conformance/es6/computedProperties/computedPropertyNamesWithStaticProperty.ts:1:7: 'C' was declared here.
var y = x;
}
[C.staticProp]() { }
~
!!! error TS2449: Class 'C' used before its declaration.
!!! related TS2728 tests/cases/conformance/es6/computedProperties/computedPropertyNamesWithStaticProperty.ts:1:7: 'C' was declared here.
}
2 changes: 2 additions & 0 deletions tests/baselines/reference/constDeclarations-useBeforeDefinition.errors.txt
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Expand Up @@ -7,6 +7,7 @@ tests/cases/compiler/constDeclarations-useBeforeDefinition.ts(8,5): error TS2448
c1;
~~
!!! error TS2448: Block-scoped variable 'c1' used before its declaration.
!!! related TS2728 tests/cases/compiler/constDeclarations-useBeforeDefinition.ts:3:11: 'c1' was declared here.
const c1 = 0;
}

Expand All @@ -15,6 +16,7 @@ tests/cases/compiler/constDeclarations-useBeforeDefinition.ts(8,5): error TS2448
v1;
~~
!!! error TS2448: Block-scoped variable 'v1' used before its declaration.
!!! related TS2728 tests/cases/compiler/constDeclarations-useBeforeDefinition.ts:9:11: 'v1' was declared here.
const v1 = 0;
}

1 change: 1 addition & 0 deletions tests/baselines/reference/constDeclarations-useBeforeDefinition2.errors.txt
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Expand Up @@ -5,6 +5,7 @@ tests/cases/compiler/file1.ts(1,1): error TS2448: Block-scoped variable 'c' used
c;
~
!!! error TS2448: Block-scoped variable 'c' used before its declaration.
!!! related TS2728 tests/cases/compiler/file2.ts:1:7: 'c' was declared here.

==== tests/cases/compiler/file2.ts (0 errors) ====
const c = 0;
1 change: 1 addition & 0 deletions tests/baselines/reference/derivedClasses.errors.txt
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Expand Up @@ -5,6 +5,7 @@ tests/cases/compiler/derivedClasses.ts(1,19): error TS2449: Class 'Color' used b
class Red extends Color {
~~~~~
!!! error TS2449: Class 'Color' used before its declaration.
!!! related TS2728 tests/cases/compiler/derivedClasses.ts:8:7: 'Color' was declared here.
public shade() {
var getHue = () => { return this.hue(); };
return getHue() + " red";
Expand Down
2 changes: 2 additions & 0 deletions tests/baselines/reference/destructuringArrayBindingPatternAndAssignment3.errors.txt
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Expand Up @@ -9,9 +9,11 @@ tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAss
const [c, d = c, e = e] = [1]; // error for e = e
~
!!! error TS2448: Block-scoped variable 'e' used before its declaration.
!!! related TS2728 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment3.ts:2:18: 'e' was declared here.
const [f, g = f, h = i, i = f] = [1]; // error for h = i
~
!!! error TS2448: Block-scoped variable 'i' used before its declaration.
!!! related TS2728 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment3.ts:3:25: 'i' was declared here.

(function ([a, b = a]) { // ok
})([1]);
Expand Down
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