Update just one gem with bundler

Here you can find a good explanation on the difference between

Update both gem and dependencies:

bundle update gem-name 

or

Update exclusively the gem:

bundle update --source gem-name

along with some nice examples of possible side-effects.

Update

As @Tim's answer says, as of Bundler 1.14 the officially-supported way to this is with bundle update --conservative gem-name.

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The way to do this is to run the following command:

bundle update --source gem-name

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It appears that with newer versions of bundler (>= 1.14) it's:

bundle update --conservative gem-name

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You simply need to specify the gem name on the command line:

bundle update gem-name

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bundle update gem-name [--major|--patch|--minor]

This also works for dependencies.

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I've used bundle update --source myself for a long time but there are scenarios where it doesn't work. Luckily, there's a gem called bundler-patch which has the goal of fixing this shortcoming.

I also wrote a short blog post about how to use bundler-patch and why bundle update --source doesn't work consistently. Also, be sure to check out a post by chrismo that explains in great detail what the --source option does.

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bundler update --source gem-name will update the revision hash in Gemfile.lock which you can compare with the last commit hash of that git branch (master by default).

GIT remote: git@github.com:organization/repo-name.git revision: c810f4a29547b60ca8106b7a6b9a9532c392c954

can be found at github.com/organization/repo-name/commits/c810f4a2 (I used shorthand 8 character commit hash for the url)

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If you want to update a single gem to a specific version:

change the version of the gem in the Gemfile bundle update

> ruby -v
ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-darwin19]
> gem -v
3.0.3
> bundle -v
Bundler version 2.1.4

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