Gemfile.lock always has changes not staged for commit

Question

I am running into this problem on a rails app I am working on. I was working on a feature branch and wanted to rebase from the most recent master. I ran the following commands:

$ git checkout master
$ git pull --rebase

If I try to checkout back to my feature branch I get the following error:

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

  modified:   Gemfile.lock

I have tried the following commands to resolve the Gemfile.lock back to aster with none of them being successful:

$ git checkout -- Gemfile.lock
$ git stash
$ git reset HEAD --hard

Every time I run a new git command I go back to the Gemfile.lock having changes not staged for commit.

Here are the following versions of libraries I am working with:

$ git --version => 2.3.3
$ bundler --version => 1.7.9

Answer 1

There must be some process running in the background or some side-effect of executing the git commands in your shell that is modifying the Gemfile.lock.

I am not familiar with rvm's magic (although that sounds plausible); here are some other things to check:

• In recent versions of Rails there is a "spring" background process that runs. Try running spring stop (or bin/spring stop or bundle exec spring stop) to gracefully terminate that process.
• Likewise if you have any other Rails-related processes like rails server, guard, zeus, sidekiq, etc. running, try shutting those down.
• You might be running a git pre-commit hook. Check the .git/hooks directory.
• git might be an alias in your shell for another command. Run alias to see a list of shell aliases.
• Your shell prompt might be executing code to do things like show the current git status and branch name in the prompt. This code would be executed after every shell command to redraw the prompt, and might have side-effects. Check your .bashrc or .bash_profile.