maxmustermann/TypeScript
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Merge pull request #3492 from Microsoft/useTypePredicatesInLib

Browse source 
Define Array.isArray using a type predicate
This commit is contained in:
Mohamed Hegazy 2015-06-12 17:39:31 -07:00
parent 72783bcae3 1a520386bb
commit 60e855e252
7 changed files with 83 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
src/lib/core.d.ts vendored
View file

@ -1150,7 +1150,7 @@ interface ArrayConstructor {
(arrayLength?: number): any[];
<T>(arrayLength: number): T[];
<T>(...items: T[]): T[];
isArray(arg: any): boolean;
isArray(arg: any): arg is Array<any>;
prototype: Array<any>;
}

19
tests/baselines/reference/isArray.js Normal file
View file

@ -0,0 +1,19 @@
//// [isArray.ts]
var maybeArray: number | number[];
if (Array.isArray(maybeArray)) {
maybeArray.length; // OK
}
else {
maybeArray.toFixed(); // OK
}
//// [isArray.js]
var maybeArray;
if (Array.isArray(maybeArray)) {
maybeArray.length; // OK
}
else {
maybeArray.toFixed(); // OK
}

22
tests/baselines/reference/isArray.symbols Normal file
View file

@ -0,0 +1,22 @@
=== tests/cases/compiler/isArray.ts ===
var maybeArray: number | number[];
>maybeArray : Symbol(maybeArray, Decl(isArray.ts, 0, 3))
if (Array.isArray(maybeArray)) {
>Array.isArray : Symbol(ArrayConstructor.isArray, Decl(lib.d.ts, 1166, 28))
>Array : Symbol(Array, Decl(lib.d.ts, 1000, 23), Decl(lib.d.ts, 1171, 11))
>isArray : Symbol(ArrayConstructor.isArray, Decl(lib.d.ts, 1166, 28))
>maybeArray : Symbol(maybeArray, Decl(isArray.ts, 0, 3))
maybeArray.length; // OK
>maybeArray.length : Symbol(Array.length, Decl(lib.d.ts, 1007, 20))
>maybeArray : Symbol(maybeArray, Decl(isArray.ts, 0, 3))
>length : Symbol(Array.length, Decl(lib.d.ts, 1007, 20))
}
else {
maybeArray.toFixed(); // OK
>maybeArray.toFixed : Symbol(Number.toFixed, Decl(lib.d.ts, 463, 37))
>maybeArray : Symbol(maybeArray, Decl(isArray.ts, 0, 3))
>toFixed : Symbol(Number.toFixed, Decl(lib.d.ts, 463, 37))
}

24
tests/baselines/reference/isArray.types Normal file
View file

@ -0,0 +1,24 @@
=== tests/cases/compiler/isArray.ts ===
var maybeArray: number | number[];
>maybeArray : number | number[]
if (Array.isArray(maybeArray)) {
>Array.isArray(maybeArray) : boolean
>Array.isArray : (arg: any) => boolean
>Array : ArrayConstructor
>isArray : (arg: any) => boolean
>maybeArray : number | number[]
maybeArray.length; // OK
>maybeArray.length : number
>maybeArray : number[]
>length : number
}
else {
maybeArray.toFixed(); // OK
>maybeArray.toFixed() : string
>maybeArray.toFixed : (fractionDigits?: number) => string
>maybeArray : number
>toFixed : (fractionDigits?: number) => string
}

12
tests/baselines/reference/library_ArraySlice.symbols
View file

@ -2,22 +2,22 @@
// Array.prototype.slice can have zero, one, or two arguments
Array.prototype.slice();
>Array.prototype.slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>Array : Symbol(Array, Decl(lib.d.ts, 1000, 23), Decl(lib.d.ts, 1171, 11))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))
Array.prototype.slice(0);
>Array.prototype.slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>Array : Symbol(Array, Decl(lib.d.ts, 1000, 23), Decl(lib.d.ts, 1171, 11))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))
Array.prototype.slice(0, 1);
>Array.prototype.slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>Array : Symbol(Array, Decl(lib.d.ts, 1000, 23), Decl(lib.d.ts, 1171, 11))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>slice : Symbol(Array.slice, Decl(lib.d.ts, 1048, 15))

4
tests/baselines/reference/returnTypeParameterWithModules.symbols
View file

@ -14,9 +14,9 @@ module M1 {
return Array.prototype.reduce.apply(ar, e ? [f, e] : [f]);
>Array.prototype.reduce.apply : Symbol(Function.apply, Decl(lib.d.ts, 228, 20))
>Array.prototype.reduce : Symbol(Array.reduce, Decl(lib.d.ts, 1129, 93), Decl(lib.d.ts, 1136, 120))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>Array.prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>Array : Symbol(Array, Decl(lib.d.ts, 1000, 23), Decl(lib.d.ts, 1171, 11))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 31))
>prototype : Symbol(ArrayConstructor.prototype, Decl(lib.d.ts, 1167, 41))
>reduce : Symbol(Array.reduce, Decl(lib.d.ts, 1129, 93), Decl(lib.d.ts, 1136, 120))
>apply : Symbol(Function.apply, Decl(lib.d.ts, 228, 20))
>ar : Symbol(ar, Decl(returnTypeParameterWithModules.ts, 1, 30))

9
tests/cases/compiler/isArray.ts Normal file
View file

@ -0,0 +1,9 @@
var maybeArray: number | number[];
if (Array.isArray(maybeArray)) {
maybeArray.length; // OK
}
else {
maybeArray.toFixed(); // OK
}