Compile-on-save with typescriptservices.js from LKG drops module prefixes

[NoelAbrahams]

Hi,

I'm using VS 2015 CTP 5 and wanted to try out typescriptservices.js from LKG of 12-Feb-2015.

Code like the following:

// my.d.ts
declare module foo.bar {
  class Baz { }
}

When referenced from another project

/// <reference path='my.d.ts' />
module foo.bar {
      var baz = <any>Baz.prototype;
}

is compiling into

var foo;
(function (foo) {
    var bar;
    (function (bar) {
        var baz = /*bar.*/Baz.prototype; // missing prefix
    })(bar = foo.bar || (foo.bar = {}));
})(foo || (foo  = {}));

This is only a problem when compile is triggered via save - generates the correct JavaScript when building.

Edit

This is a little bit more involved: The combine JS into output file also needs to be set. The faulty JS is generated not when the code file itself is saved, but when a sibling file in the same project is saved (which would cause the combined file to be generated).

[NoelAbrahams]

This bug is present in 1.5 beta. I would have thought it's critical as it produces JavaScript that fails at runtime.

[mhegazy]

@JsonFreeman can you take a look.

[JsonFreeman]

@NoelAbrahams do you have noEmitOnError explicitly set to false in your project? I've investigated this with @vladima, but the only way we were able to reproduce it is to set noEmitOnError to false.

[mhegazy]

I got it to repro earlier today without any changes. You just need to create a project add two files as listed above set --out, touch both files and then save the one with declare module.

[vladima]

@mhegazy That is very interesting. What is special in scenario with '--out' is that you''ll trigger save in one file but during emit you'll examine the entire project. Crux of the problem: initial file will be typechecked however other files -- not so nodeLinks \ symbolLinks for them will not be populated -> incorrect emit. Why it works today: see line 215 in program.ts - here we call getPreEmitDiagnostics that will query semantic diagnostics for all files and so all files will be typechecked. However this function is called only if noEmitOnError flag is set. If it is not set then emit will almost always be incorrect and we've verified that.

[mhegazy]

That makes sense.. --noEmitOnError is set in projects by default...

[JsonFreeman]

@mhegazy This brings us back to the question, how did it repro for you if you had noEmitOnError turned on?

[JsonFreeman]

@NoelAbrahams please try upgrading your VS with my fix, and see if it fixes your problem.