Build: Property X does not exist on type Y.

[bertrand-alain]

Randomly during build, the typescript compiler will issue such errors while the class does actually have the property set as static:

class MyClass
{
    static MyProp:string="Hello";
    static MyFunc()
    {
       console.log(MyClass.MyProp);
    }
}

As during the next build it may work, this is certainly a compiler bug.

Using Visual Studio 2015 -> TypeScript for MS VS 1.6.3.0

[mhegazy]

@bertrandpsi can you share more details?

[mhegazy]

a minimal self-contained msbuild project showing the issue would be ideal.

[bertrand-alain]

@mhegazy will prepare it on Monday when I'm back at work. But basically what I do is a ts file pro class, and then join then on the build, still, the property issue seems to be triggered from the same class calling static properties so it should not be even an issue of class definition in the wrong order or other similar things.

Remember that this is not always the case but like once every 10 build or so. Could be a timing issue?

[mhegazy]

wounder if it is related to #4185. We tracked the issue down to bug in the JS engine. if you have a consistent repro that shown the issue (say if i run the same command 100 times it fails once), then we can run it on nodejs and see if it does not repro, and that will point us to the engine. if not then it is a TypeScript compiler issue or a build system race condition.

[bertrand-alain]

@mhegazy Tried to extract from my project and reproduce the bug and wasn't able. If you want I can send you via email or other means my original project to let you dig into.

[romanresh]

Have the same problem on our CI server. This error is reproduced randomly for all static members in a project (.csproj, MSBUILD is used for building). One moment - if this error is occurred once, then build will fail (on this virtual machine) until I build the project via Visual Studio.
OS: Win10, msbuild: 12.0.40629.

[bertrand-alain]

The full message I get is:
C:\tfs\Inventory\SharpInventory\IV4\TypeScript\GUI\DatePicker.ts(16,20): error TS2339: Build: Property 'currentPickers' does not exist on type 'typeof DatePicker'.

While on the DatePicker TS class I clearly have it:
class DatePicker implements IDisposable
{
static currentPickers: DatePicker[] = [];
...
}

[mhegazy]

since it is not consistent, i would think it is the same as #4185. @bertrandpsi and @romanresh can you try with node tsc.js instead of tsc.exe and see if there is any difference?

[Mauricio2Code]

I'm experiencing the same thing. Using Visual Studio 2013-> TypeScript for MS VS 1.6.3.0 and this is the code that I'm using:

class MessageBus {

    private static _instance: MessageBus = new MessageBus();
..
}

The compiler errors intermittently with "Build: Property '_instance' does not exist on type 'typeof MessageBus'.