Deterministic build order

[srolel]

The bundled output's internal package order seems to be random. I'm using a hash for versioning that means it changes every time, so I always cache-bust when I upload, regardless of actual changes.

[guybedford]

Good point, we should make the order well-defined based on the dependency structure.

[guybedford]

Fixed by @Munter in #309.

[guybedford]

Released in 0.14.0.

[carlosagsmendes]

@Munter and @guybedford I'm facing some issues when hashing due to inconsistencies in the modules order.

In the Trace.getTreeModulesPostOrder I get the following order:

In the builder.bundle I get the following order in the output.modules:

I'm using the in-memory process:

builder.bundle('myModule.js', { minify: true }).then(function(output) {
  output.source;    // generated bundle source
  output.sourceMap; // generated bundle source map
  output.modules;   // array of module names defined in the bundle
});

And in the builder.bundle I get the following order in the output.source:

editors/single-file-upload/single-file-upload-template.html!github:systemjs/plugin-text@0.0.2
github:blueimp/jQuery-File-Upload@9.11.2/jquery.fileupload
github:blueimp/jQuery-File-Upload@9.11.2
github:blueimp/jQuery-File-Upload@9.11.2/jquery.fileupload-process
github:blueimp/jQuery-File-Upload@9.11.2/jquery.fileupload-validate
github:blueimp/jQuery-File-Upload@9.11.2/jquery.iframe-transport
editors/single-file-upload/single-file-upload-bootstrapper
editors/single-file-upload/single-file-upload-viewmodel
infrastructure/jquery-file-upload-custom

The order is always different.

Shouldn't it always be the same?

Thanks

[Munter]

Hmm. There was a big refactoring with breaking changes which happened just around the time where the post order traversal was merged in. Maybe we missed a call to get the order somewhere

[guybedford]

@carlosagsmendes thanks for posting! This was an oversight in the promises chains, fixed in c8c947e.

[carlosagsmendes]

Thanks @guybedford I've just tested it with the 0.14.9 version and I'm still getting different results with multiple runs.

output.modules order (when building in memory) is still not consistent:

Run1:

Run2:

Items 3 and 4 order changed.

Here's how they are being imported:

import 'jquery-file-upload';
import 'jquery-ui/ui/widget';
import 'jquery-file-upload/jquery.fileupload-process';
import 'jquery-file-upload/jquery.fileupload-validate';
// This is only for IE9
import 'jquery-file-upload/jquery.iframe-transport';

[guybedford]

@carlosagsmendes when you say the last export is only for IE9 are you setting that via metadata.deps perhaps? I'm just wondering where the non-determinism is creeping in.

[carlosagsmendes]

Hi, no, this is just a simple comment so we can remember why we're doing this import.

Here's a copy of my package.json. Could it be something related with dependencies?

https://gist.github.com/carlosagsmendes/eaa44a2e262e07a98f92#file-package-json-L153

[guybedford]

@carlosagsmendes output.modules is not actually deterministic, while the build itself should be. Are you definitely seeing the output source file as non-deterministic here as well?