Package 'unittest' is depended on from both sources 'sdk' and 'hosted

[DartBot]

Originally opened as dart-lang/sdk#7127

This issue was originally filed by scottishph...@gmail.com

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What steps will reproduce the problem?

1. Create a pubspec.yaml for a library like:
     name: nigori
     description: Secrets in the cloud
     
     dependencies:
       unittest: { hosted: unittest }
2. Depend on it in a application pubspec.yaml like:
     name: PassgoriExtension
     description: Password storage using Nigori
     
     dependencies:
       js: { hosted: js }
       nigori:
         git: file:///home/drt24/dart/nigori/
3. On saving the second pubspec.yaml the following error is produced by pub install:
     Running pub install ...
     Pub install fail, Resolving dependencies...
     Package 'unittest' is depended on from both sources 'sdk' and 'hosted'.

What is the expected output? What do you see instead?
I expect dependencies to be correctly resolved. Instead they fail. Changing unittest: { hosted: unittest } to unittest: { sdk: unittest } results in the same error message. Changing js: { hosted: js } to js: { sdk: js } results in:
  Running pub install ...
  Pub install fail, Resolving dependencies...
  Entry null is not a supported type.

What version of the product are you using? On what operating system?
Dart Editor version 0.2.6_r15355
Dart SDK version 0.2.6.0_r15355
$ uname -a
Linux 3.2.0-34-generic #­53-Ubuntu SMP Thu Nov 15 10:48:16 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 12.04.1 LTS

Please provide any additional information below.

I expect it to just work but failing that something in the error message indicating where the conflicting constraints on sources are coming from would greatly aid debugging.

[DartBot]

This comment was originally written by scottishph...@gmail.com

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Ahh oops I didn't enter a one-line summary and I can't see how to edit it. If someone else can then: "Package 'unittest' is depended on from both sources 'sdk' and 'hosted'." is probably suitably descriptive as I don't know what the underlying problem is.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/3276024?v=3" align="left" width="48" height="48"hspace="10"> Comment by anders-sandholm

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Added Area-Pub, Triaged labels.
Changed the title to: "Package 'unittest' is depended on from both sources 'sdk' and 'hosted".

[DartBot]

This comment was originally written by scottishph...@gmail.com

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I have a patch that makes the error messages more informative such that once I had implemented this patch I realised what the problem was straight away. https://codereview.chromium.org/11450030/

The problem was that I was not committing changes to the nigori library before expecting them to be visible to the PassgoriExtension application.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/46275?v=3" align="left" width="48" height="48"hspace="10"> Comment by munificent

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  dependencies:
    unittest: { hosted: unittest }

Just FYI, this more terse way to write that is:

  dependencies:
    unittest: any

Entry null is not a supported type.

That looks like a YAML parsing error (and not a very helpful error message). We've got a bug filed already to improve our YAML error messages, which we should definitely do.

I expect it to just work but failing that something in the error message indicating where the conflicting constraints on sources are coming from would greatly aid debugging.

Once everything depending on unittest has moved over to hosted this problem should go away but you're that it's painful right now that things don't just work.

You comment on better error messages for conflicts is spot on. Fortunately, I fixed that yesterday: https://codereview.chromium.org/11445034/

Thanks for the patch, though. I definitely appreciate you helping with a solution even if you happened to be a few hours too late. :)

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Added Duplicate label.
Marked as being merged into #216.