Skip to content

Port "check usage before declaration for decorators" #1829

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Oct 6, 2025
Merged

Port "check usage before declaration for decorators" #1829

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
8031bd3
Port "check usage before declaration for decorators"
Andarist Oct 4, 2025
aab4f07
Merge remote-tracking branch 'origin/main' into port/50372
Andarist Oct 6, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 10 additions & 1 deletion internal/checker/checker.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1906,7 +1906,7 @@ func (c *Checker) isBlockScopedNameDeclaredBeforeUse(declaration *ast.Node, usag
func (c *Checker) isUsedInFunctionOrInstanceProperty(usage *ast.Node, declaration *ast.Node, declContainer *ast.Node) bool {
for current := usage; current != nil && current != declContainer; current = current.Parent {
if ast.IsFunctionLike(current) {
return true
return ast.GetImmediatelyInvokedFunctionExpression(current) == nil
}
if ast.IsClassStaticBlockDeclaration(current) {
return declaration.Pos() < usage.Pos()
Expand All @@ -1933,6 +1933,15 @@ func (c *Checker) isUsedInFunctionOrInstanceProperty(usage *ast.Node, declaratio
}
}
}
if current.Parent != nil && ast.IsDecorator(current.Parent) && current.Parent.AsDecorator().Expression == current {
decorator := current.Parent.AsDecorator()
if ast.IsParameter(decorator.Parent) {
return c.isUsedInFunctionOrInstanceProperty(decorator.Parent.Parent.Parent, declaration, declContainer)
}
if ast.IsMethodDeclaration(decorator.Parent) {
return c.isUsedInFunctionOrInstanceProperty(decorator.Parent.Parent, declaration, declContainer)
}
}
}
return false
}
Expand Down
14 changes: 13 additions & 1 deletion testdata/baselines/reference/submodule/compiler/blockScopedVariablesUseBeforeDef.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,9 +5,12 @@ blockScopedVariablesUseBeforeDef.ts(100,12): error TS2448: Block-scoped variable
blockScopedVariablesUseBeforeDef.ts(111,28): error TS2448: Block-scoped variable 'a' used before its declaration.
blockScopedVariablesUseBeforeDef.ts(112,21): error TS2448: Block-scoped variable 'a' used before its declaration.
blockScopedVariablesUseBeforeDef.ts(122,22): error TS2448: Block-scoped variable 'a' used before its declaration.
blockScopedVariablesUseBeforeDef.ts(128,9): error TS2448: Block-scoped variable 'foo' used before its declaration.
blockScopedVariablesUseBeforeDef.ts(131,9): error TS2448: Block-scoped variable 'foo' used before its declaration.
blockScopedVariablesUseBeforeDef.ts(153,20): error TS2450: Enum 'Enum' used before its declaration.


==== blockScopedVariablesUseBeforeDef.ts (7 errors) ====
==== blockScopedVariablesUseBeforeDef.ts (10 errors) ====
function foo0() {
let a = x;
~
Expand Down Expand Up @@ -157,9 +160,15 @@ blockScopedVariablesUseBeforeDef.ts(122,22): error TS2448: Block-scoped variable
const promise = (async () => {
promise
foo
~~~
!!! error TS2448: Block-scoped variable 'foo' used before its declaration.
!!! related TS2728 blockScopedVariablesUseBeforeDef.ts:134:11: 'foo' is declared here.
await null
promise
foo
~~~
!!! error TS2448: Block-scoped variable 'foo' used before its declaration.
!!! related TS2728 blockScopedVariablesUseBeforeDef.ts:134:11: 'foo' is declared here.
})()

const foo = 1;
Expand All @@ -182,6 +191,9 @@ blockScopedVariablesUseBeforeDef.ts(122,22): error TS2448: Block-scoped variable

function foo18() {
let a = (() => Enum.Yes)();
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 blockScopedVariablesUseBeforeDef.ts:154:10: 'Enum' is declared here.
enum Enum {
No = 0,
Yes = 1,
Expand Down
44 changes: 0 additions & 44 deletions ...a/baselines/reference/submodule/compiler/blockScopedVariablesUseBeforeDef.errors.txt.diff
View file
Open in desktop

This file was deleted.

34 changes: 33 additions & 1 deletion testdata/baselines/reference/submodule/compiler/decoratorUsedBeforeDeclaration.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,9 +4,17 @@ decoratorUsedBeforeDeclaration.ts(2,7): error TS2450: Enum 'Enum' used before it
decoratorUsedBeforeDeclaration.ts(4,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
decoratorUsedBeforeDeclaration.ts(4,11): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(5,9): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(12,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
decoratorUsedBeforeDeclaration.ts(12,11): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(13,9): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(18,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
decoratorUsedBeforeDeclaration.ts(24,11): error TS2448: Block-scoped variable 'lambda' used before its declaration.
decoratorUsedBeforeDeclaration.ts(24,18): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(24,33): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(28,11): error TS2448: Block-scoped variable 'lambda' used before its declaration.


==== decoratorUsedBeforeDeclaration.ts (6 errors) ====
==== decoratorUsedBeforeDeclaration.ts (14 errors) ====
@lambda(Enum.No)
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
Expand Down Expand Up @@ -37,22 +45,46 @@ decoratorUsedBeforeDeclaration.ts(5,9): error TS2450: Enum 'Enum' used before it
}

@lambda(Enum.No)
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
@deco(Enum.No)
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
greet() {
return "Hello, " + this.greeting;
}

@lambda
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
@deco
greet1() {
return "Hello, " + this.greeting;
}

greet2(@lambda(Enum.No) @deco(Enum.No) param) {
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
return "Hello, " + this.greeting;
}

greet3(@lambda @deco param) {
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
return "Hello, " + this.greeting;
}
}
Expand Down
72 changes: 10 additions & 62 deletions ...ata/baselines/reference/submodule/compiler/decoratorUsedBeforeDeclaration.errors.txt.diff
View file
Open in desktop
Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the rest of this diff should go away with #1828

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'll wait to look at the PR until that one gets through the merge queue.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

synced with main now and it's gone :)

Original file line number Diff line number Diff line change
Expand Up @@ -7,24 +7,19 @@
-decoratorUsedBeforeDeclaration.ts(4,16): error TS2729: Property 'No' is used before its initialization.
decoratorUsedBeforeDeclaration.ts(5,9): error TS2450: Enum 'Enum' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(5,14): error TS2729: Property 'No' is used before its initialization.
-decoratorUsedBeforeDeclaration.ts(12,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(12,11): error TS2450: Enum 'Enum' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(13,9): error TS2450: Enum 'Enum' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(18,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(24,11): error TS2448: Block-scoped variable 'lambda' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(24,18): error TS2450: Enum 'Enum' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(24,33): error TS2450: Enum 'Enum' used before its declaration.
-decoratorUsedBeforeDeclaration.ts(28,11): error TS2448: Block-scoped variable 'lambda' used before its declaration.
-
-
decoratorUsedBeforeDeclaration.ts(12,4): error TS2448: Block-scoped variable 'lambda' used before its declaration.
decoratorUsedBeforeDeclaration.ts(12,11): error TS2450: Enum 'Enum' used before its declaration.
decoratorUsedBeforeDeclaration.ts(13,9): error TS2450: Enum 'Enum' used before its declaration.
@@= skipped -13, +11 lines =@@
decoratorUsedBeforeDeclaration.ts(28,11): error TS2448: Block-scoped variable 'lambda' used before its declaration.


-==== decoratorUsedBeforeDeclaration.ts (16 errors) ====
+
+
+==== decoratorUsedBeforeDeclaration.ts (6 errors) ====
+==== decoratorUsedBeforeDeclaration.ts (14 errors) ====
@lambda(Enum.No)
~~~~~~
!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
@@= skipped -33, +23 lines =@@
@@= skipped -20, +20 lines =@@
~~~~
!!! error TS2450: Enum 'Enum' used before its declaration.
!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
Expand All @@ -40,51 +35,4 @@
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:36:3: 'No' is declared here.
greeting: string;

constructor(message: string) {
@@= skipped -17, +11 lines =@@
}

@lambda(Enum.No)
- ~~~~~~
-!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
- ~~~~
-!!! error TS2450: Enum 'Enum' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
@deco(Enum.No)
- ~~~~
-!!! error TS2450: Enum 'Enum' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
greet() {
return "Hello, " + this.greeting;
}

@lambda
- ~~~~~~
-!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
@deco
greet1() {
return "Hello, " + this.greeting;
}

greet2(@lambda(Enum.No) @deco(Enum.No) param) {
- ~~~~~~
-!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
- ~~~~
-!!! error TS2450: Enum 'Enum' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
- ~~~~
-!!! error TS2450: Enum 'Enum' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:35:6: 'Enum' is declared here.
return "Hello, " + this.greeting;
}

greet3(@lambda @deco param) {
- ~~~~~~
-!!! error TS2448: Block-scoped variable 'lambda' used before its declaration.
-!!! related TS2728 decoratorUsedBeforeDeclaration.ts:40:7: 'lambda' is declared here.
return "Hello, " + this.greeting;
}
}
constructor(message: string) {