Skip to content

Array.prototype.slice() returns this #5123

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

Closed
wants to merge 5 commits into from
Closed

Array.prototype.slice() returns this #5123

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
8d4b117
Update tests that use array slicing
sandersn Oct 5, 2015
843654a
Array slice with no arguments has return type this
sandersn Oct 5, 2015
d492366
Rebaseline test symbols after lib.d.ts change
sandersn Oct 5, 2015
8924205
Add test cases for unary and binary slice to tuple
sandersn Oct 6, 2015
7395366
Merge branch 'master' into nullary-array-slice-returns-this
sandersn Oct 6, 2015
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
6 changes: 6 additions & 0 deletions src/lib/core.d.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1032,6 +1032,12 @@ interface Array<T> {
* Removes the first element from an array and returns it.
*/
shift(): T;

/**
* Returns a shallow copy of an array.
*/
slice(): this;

/**
* Returns a section of an array.
* @param start The beginning of the specified portion of the array.
Expand Down
1 change: 1 addition & 0 deletions tests/baselines/reference/implementArrayInterface.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@ declare class MyArray<T> implements Array<T> {
push(...items: T[]): number;
reverse(): T[];
shift(): T;
slice(): this;
slice(start?: number, end?: number): T[];
sort(compareFn?: (a: T, b: T) => number): T[];
splice(start: number): T[];
Expand Down
191 changes: 97 additions & 94 deletions tests/baselines/reference/implementArrayInterface.symbols
View file
Open in desktop

Large diffs are not rendered by default.

5 changes: 4 additions & 1 deletion tests/baselines/reference/implementArrayInterface.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -46,8 +46,11 @@ declare class MyArray<T> implements Array<T> {
>shift : () => T
>T : T

slice(): this;
>slice : { (): this; (start?: number, end?: number): T[]; }

slice(start?: number, end?: number): T[];
>slice : (start?: number, end?: number) => T[]
>slice : { (): this; (start?: number, end?: number): T[]; }
>start : number
>end : number
>T : T
Expand Down
22 changes: 22 additions & 0 deletions tests/baselines/reference/library_ArraySlice.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,22 @@
tests/cases/compiler/library_ArraySlice.ts(9,5): error TS2322: Type 'number[]' is not assignable to type '[number, number]'.
Property '0' is missing in type 'number[]'.
tests/cases/compiler/library_ArraySlice.ts(10,5): error TS2322: Type 'number[]' is not assignable to type '[number, number]'.


==== tests/cases/compiler/library_ArraySlice.ts (2 errors) ====
// Array.prototype.slice can have zero, one, or two arguments
Array.prototype.slice();
Array.prototype.slice(0);
Array.prototype.slice(0, 1);

// Array.prototype.slice returns this with zero arguments, allowing tuple slicing
let t1: [number, number] = [1, 2];
let t2: [number, number] = t1.slice();
let t3: [number, number] = t1.slice(0);
~~
!!! error TS2322: Type 'number[]' is not assignable to type '[number, number]'.
!!! error TS2322: Property '0' is missing in type 'number[]'.
let t4: [number, number] = t1.slice(0,1);
~~
!!! error TS2322: Type 'number[]' is not assignable to type '[number, number]'.

14 changes: 13 additions & 1 deletion tests/baselines/reference/library_ArraySlice.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2,10 +2,22 @@
// Array.prototype.slice can have zero, one, or two arguments
Array.prototype.slice();
Array.prototype.slice(0);
Array.prototype.slice(0, 1);
Array.prototype.slice(0, 1);

// Array.prototype.slice returns this with zero arguments, allowing tuple slicing
let t1: [number, number] = [1, 2];
let t2: [number, number] = t1.slice();
let t3: [number, number] = t1.slice(0);
let t4: [number, number] = t1.slice(0,1);


//// [library_ArraySlice.js]
// Array.prototype.slice can have zero, one, or two arguments
Array.prototype.slice();
Array.prototype.slice(0);
Array.prototype.slice(0, 1);
// Array.prototype.slice returns this with zero arguments, allowing tuple slicing
var t1 = [1, 2];
var t2 = t1.slice();
var t3 = t1.slice(0);
var t4 = t1.slice(0, 1);
23 changes: 0 additions & 23 deletions tests/baselines/reference/library_ArraySlice.symbols
View file
Open in desktop

This file was deleted.

29 changes: 0 additions & 29 deletions tests/baselines/reference/library_ArraySlice.types
View file
Open in desktop

This file was deleted.

12 changes: 6 additions & 6 deletions tests/baselines/reference/library_RegExpExecArraySlice.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,17 +5,17 @@ var regExpExecArrayValue: RegExpExecArray;
>RegExpExecArray : Symbol(RegExpExecArray, Decl(lib.d.ts, --, --))

regExpExecArrayValue.slice();
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
>regExpExecArrayValue : Symbol(regExpExecArrayValue, Decl(library_RegExpExecArraySlice.ts, 1, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))

regExpExecArrayValue.slice(0);
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
>regExpExecArrayValue : Symbol(regExpExecArrayValue, Decl(library_RegExpExecArraySlice.ts, 1, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))

regExpExecArrayValue.slice(0,1);
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>regExpExecArrayValue.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
>regExpExecArrayValue : Symbol(regExpExecArrayValue, Decl(library_RegExpExecArraySlice.ts, 1, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))

14 changes: 7 additions & 7 deletions tests/baselines/reference/library_RegExpExecArraySlice.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,23 +5,23 @@ var regExpExecArrayValue: RegExpExecArray;
>RegExpExecArray : RegExpExecArray

regExpExecArrayValue.slice();
>regExpExecArrayValue.slice() : string[]
>regExpExecArrayValue.slice : (start?: number, end?: number) => string[]
>regExpExecArrayValue.slice() : RegExpExecArray
>regExpExecArrayValue.slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }
>regExpExecArrayValue : RegExpExecArray
>slice : (start?: number, end?: number) => string[]
>slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }

regExpExecArrayValue.slice(0);
>regExpExecArrayValue.slice(0) : string[]
>regExpExecArrayValue.slice : (start?: number, end?: number) => string[]
>regExpExecArrayValue.slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }
>regExpExecArrayValue : RegExpExecArray
>slice : (start?: number, end?: number) => string[]
>slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }
>0 : number

regExpExecArrayValue.slice(0,1);
>regExpExecArrayValue.slice(0,1) : string[]
>regExpExecArrayValue.slice : (start?: number, end?: number) => string[]
>regExpExecArrayValue.slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }
>regExpExecArrayValue : RegExpExecArray
>slice : (start?: number, end?: number) => string[]
>slice : { (): RegExpExecArray; (start?: number, end?: number): string[]; }
>0 : number
>1 : number

14 changes: 7 additions & 7 deletions tests/baselines/reference/thisTypeInTuples.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,27 +4,27 @@ interface Array<T> {
>T : Symbol(T, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 16))

slice(): this;
>slice : Symbol(slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>slice : Symbol(slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
}

let t: [number, string] = [42, "hello"];
>t : Symbol(t, Decl(thisTypeInTuples.ts, 4, 3))

let a = t.slice();
>a : Symbol(a, Decl(thisTypeInTuples.ts, 5, 3))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t : Symbol(t, Decl(thisTypeInTuples.ts, 4, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))

let b = t.slice(1);
>b : Symbol(b, Decl(thisTypeInTuples.ts, 6, 3))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t : Symbol(t, Decl(thisTypeInTuples.ts, 4, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))

let c = t.slice(0, 1);
>c : Symbol(c, Decl(thisTypeInTuples.ts, 7, 3))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t.slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>t : Symbol(t, Decl(thisTypeInTuples.ts, 4, 3))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))
>slice : Symbol(Array.slice, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(thisTypeInTuples.ts, 0, 20))

14 changes: 7 additions & 7 deletions tests/baselines/reference/thisTypeInTuples.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ interface Array<T> {
>T : T

slice(): this;
>slice : { (start?: number, end?: number): T[]; (): this; }
>slice : { (): this; (start?: number, end?: number): T[]; (): this; }
}

let t: [number, string] = [42, "hello"];
Expand All @@ -16,24 +16,24 @@ let t: [number, string] = [42, "hello"];
let a = t.slice();
>a : [number, string]
>t.slice() : [number, string]
>t.slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t.slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t : [number, string]
>slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }

let b = t.slice(1);
>b : (number | string)[]
>t.slice(1) : (number | string)[]
>t.slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t.slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t : [number, string]
>slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>1 : number

let c = t.slice(0, 1);
>c : (number | string)[]
>t.slice(0, 1) : (number | string)[]
>t.slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t.slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>t : [number, string]
>slice : { (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>slice : { (): [number, string]; (start?: number, end?: number): (number | string)[]; (): [number, string]; }
>0 : number
>1 : number

1 change: 1 addition & 0 deletions tests/cases/compiler/implementArrayInterface.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,7 @@ declare class MyArray<T> implements Array<T> {
push(...items: T[]): number;
reverse(): T[];
shift(): T;
slice(): this;
slice(start?: number, end?: number): T[];
sort(compareFn?: (a: T, b: T) => number): T[];
splice(start: number): T[];
Expand Down
8 changes: 7 additions & 1 deletion tests/cases/compiler/library_ArraySlice.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,4 +1,10 @@
// Array.prototype.slice can have zero, one, or two arguments
Array.prototype.slice();
Array.prototype.slice(0);
Array.prototype.slice(0, 1);
Array.prototype.slice(0, 1);

// Array.prototype.slice returns this with zero arguments, allowing tuple slicing
let t1: [number, number] = [1, 2];
let t2: [number, number] = t1.slice();
Copy link
Contributor

Choose a reason for hiding this comment

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

Could you add these test as well

let t3:[number, number] = t1.slice(0);
let t3:[number, number] = t1.slice(0,1);

Copy link
Member Author

Choose a reason for hiding this comment

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

Sure, although those are negative tests -- only slice() returns this.

let t3: [number, number] = t1.slice(0);
let t4: [number, number] = t1.slice(0,1);