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=== tests/cases/conformance/expressions/typeGuards/typeGuardOfFormThisMember.ts ===
// There's a 'File' class in the stdlib, wrap with a namespace to avoid collision
namespace Test {
>Test : typeof Test
export class FileSystemObject {
>FileSystemObject : FileSystemObject
isFSO: this is FileSystemObject;
>isFSO : boolean
get isFile(): this is File {
>isFile : boolean
return this instanceof File;
>this instanceof File : boolean
>this : this
>File : typeof File
}
set isFile(param) {
>isFile : boolean
>param : boolean
// noop
}
get isDirectory(): this is Directory {
>isDirectory : boolean
return this instanceof Directory;
>this instanceof Directory : boolean
>this : this
>Directory : typeof Directory
}
isNetworked: this is (Networked & this);
>isNetworked : boolean
constructor(public path: string) {}
>path : string
}
export class File extends FileSystemObject {
>File : File
>FileSystemObject : FileSystemObject
constructor(path: string, public content: string) { super(path); }
>path : string
>content : string
>super(path) : void
>super : typeof FileSystemObject
>path : string
}
export class Directory extends FileSystemObject {
>Directory : Directory
>FileSystemObject : FileSystemObject
children: FileSystemObject[];
>children : FileSystemObject[]
}
export interface Networked {
host: string;
>host : string
}
let file: FileSystemObject = new File("foo/bar.txt", "foo");
>file : FileSystemObject
>new File("foo/bar.txt", "foo") : File
>File : typeof File
>"foo/bar.txt" : "foo/bar.txt"
>"foo" : "foo"
file.isNetworked = false;
>file.isNetworked = false : false
>file.isNetworked : boolean
>file : FileSystemObject
>isNetworked : boolean
>false : false
file.isFSO = file.isFile;
>file.isFSO = file.isFile : boolean
>file.isFSO : boolean
>file : FileSystemObject
>isFSO : boolean
>file.isFile : boolean
>file : FileSystemObject
>isFile : boolean
file.isFile = true;
>file.isFile = true : true
>file.isFile : boolean
>file : FileSystemObject
>isFile : boolean
>true : true
let x = file.isFile;
>x : boolean
>file.isFile : true
>file : FileSystemObject
>isFile : true
if (file.isFile) {
>file.isFile : true
>file : FileSystemObject
>isFile : true
file.content;
>file.content : any
>file : FileSystemObject
>content : any
if (file.isNetworked) {
>file.isNetworked : false
>file : FileSystemObject
>isNetworked : false
file.host;
>file.host : any
>file : FileSystemObject
>host : any
file.content;
>file.content : any
>file : FileSystemObject
>content : any
}
}
else if (file.isDirectory) {
>file.isDirectory : boolean
>file : FileSystemObject
>isDirectory : boolean
file.children;
>file.children : any
>file : FileSystemObject
>children : any
}
else if (file.isNetworked) {
>file.isNetworked : false
>file : FileSystemObject
>isNetworked : false
file.host;
>file.host : any
>file : FileSystemObject
>host : any
}
interface GenericLeadGuard<T> extends GenericGuard<T> {
lead(): void;
>lead : () => void
}
interface GenericFollowerGuard<T> extends GenericGuard<T> {
follow(): void;
>follow : () => void
}
interface GenericGuard<T> {
target: T;
>target : T
isLeader: this is (GenericLeadGuard<T>);
>isLeader : boolean
isFollower: this is GenericFollowerGuard<T>;
>isFollower : boolean
}
let guard: GenericGuard<File>;
>guard : GenericGuard<File>
if (guard.isLeader) {
>guard.isLeader : boolean
>guard : GenericGuard<File>
>isLeader : boolean
guard.lead();
>guard.lead() : any
>guard.lead : any
>guard : GenericGuard<File>
>lead : any
}
else if (guard.isFollower) {
>guard.isFollower : boolean
>guard : GenericGuard<File>
>isFollower : boolean
guard.follow();
>guard.follow() : any
>guard.follow : any
>guard : GenericGuard<File>
>follow : any
}
interface SpecificGuard {
isMoreSpecific: this is MoreSpecificGuard;
>isMoreSpecific : boolean
}
interface MoreSpecificGuard extends SpecificGuard {
do(): void;
>do : () => void
}
let general: SpecificGuard;
>general : SpecificGuard
if (general.isMoreSpecific) {
>general.isMoreSpecific : boolean
>general : SpecificGuard
>isMoreSpecific : boolean
general.do();
>general.do() : any
>general.do : any
>general : SpecificGuard
>do : any
}
}
|
