dep does not import same revision for dependencies that are declared in Godeps.json

[dlsniper]

In the following project https://github.com/gopheracademy/gopher , running dep init.

See:

• Godeps.json https://pastebin.com/pvGktSk0
• Gopkg.lock https://pastebin.com/zkcZecNL

Observe the difference between versions for github.com/nlopes/slack:

• godeps: b5c480d57859099b2050e071f2df92c2b3170ced
• dep: c86337c0ef2486a15edd804355d9c73d2f2caed1

dep version: f134697
gopher version: 7bb1dd8a82cff5fb8172bcb768d0decd9ba80420

[AlekSi]

I think it is the same as #1069.

[dlsniper]

Imho, this one is different. While #1069 tracks the fact that unneeded packages are vendored as well as unneeded repositories (if that's what dep is tracking at).

However, this one reflects a bigger problem. Currently dep cannot be trusted to cleanly migrate a project from an existing package management system to dep without potentially breaking changes. In this case, gopher is unbuildable after running dep . The difference in versions / commit hashes is tracked by this issue.

[carolynvs]

Agreed, dep cannot currently be trusted to not make changes after the importers are run. The issue which tracks that is #908.

[dlsniper]

@carolynvs do you think I should close this in favor of #908?

[carolynvs]

Before closing, I'd like to understand if the issue was that our godep importer didn't preserve the original revision in the lock, or if the constraints later caused the solver to pick a different version for the slack project.

Can you run dep init -v and provide the console output and resulting Gopkg.toml/lock files?

[sdboyer]

i did the dep init -v - this is the relevant bit, where the original rev gets rejected:

(15)  ? attempt github.com/nlopes/slack with 1 pkgs; at least 1 versions to try
(21)      try github.com/nlopes/slack@b5c480d57859099b2050e071f2df92c2b3170ced
(22)  ✗   github.com/nlopes/slack@b5c480d57859099b2050e071f2df92c2b3170ced not allowed by constraint ^0.1.0-2-gb5c480d:
(22)      ^0.1.0-2-gb5c480d from (root)
(21)      try github.com/nlopes/slack@v0.1.0
(21)  ✓ select github.com/nlopes/slack@v0.1.0 w/1 pkgs

@carolynvs i think we have an issue open for this already? trying to use the comments from Godeps.json as constraints seems to not be having the desired effect.

[carolynvs]

@sdboyer Ah okay, yeah this is part of a bigger question that I had about locking to untagged revisions during import. Can you take a look at my question and let me know what you think? #939 (comment)