dep: use build script to maintain all ldflags

[cblecker]

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• Have you checked that there aren't other open pull requests for the same formula update/change?
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This modifies the build process for dep to use the build script they use to publish real releases. This ensures that the version information is fully populated. It was also necessary to swap over to tag/revision from url/sha to accomplish this.

This ensures that if the project uses additional ldflags in the future, that they will be retained.

Before:

dep:
 version     : 0.4.1
 build date  : 
 git hash    : 
 go version  : go1.9.3
 go compiler : gc
 platform    : darwin/amd64

After:

dep:
 version     : v0.4.1
 build date  : 2018-01-27
 git hash    : 37d9ea0
 go version  : go1.9.3
 go compiler : gc
 platform    : darwin/amd64

[cblecker]

I'm not sure what's up with the failure. Doesn't appear to be related, and doesn't appear when I run locally.

[ilovezfs]

@cblecker it's caused by Homebrew/brew#2601

[cblecker]

@ilovezfs I’m not sure what the right path would be to fix this, if that’s the case. We aren’t explicitly bumping the version, but swapping from url/sha -> tag/revision in order to expose that information in the version message

[ilovezfs]

The right path is to ignore it, so I've merged this! Thanks for the PR. At some point, we will need to fix it on the brew side, but since it only occurs once during the checksum -> tag transition, I haven't bothered anyone about it yet or done anything about it myself.

[cblecker]

Awesome! Thanks as always, @ilovezfs! 👍

[ilovezfs]

You're welcome!