Add db:migrate:pending to check for pending migrations, closes #165

[golmansax]

Threw together a pull to tackle #165, got tests to pass locally. A good amount of the src and test code was copied from db:migrate, so definitely open to feedback!

[mention-bot]

@golmansax, thanks for your PR! By analyzing the history of the files in this pull request, we identified @sdepold, @Americas and @cusspvz to be potential reviewers.

[cusspvz]

process.exit(255);?
I wouldn't exit with the same exit code as if it were pending migrations.

[cusspvz]

If there is an error, this test will pass because errors are exiting with the same exit code as "pending migrations".

[golmansax]

@cusspvz Thanks for the fast reply! It looks like an exit code of 1 is used throughout the repo, so I instead changed the pending migration exit code to 3 (wasn't sure what exit code to choose, and 2 is reserved according to http://www.tldp.org/LDP/abs/html/exitcodes.html)

You can see the changes in 69391de. Thoughts?

[cusspvz]

I've took a time to look the repo and seems it only exits with 1 when it has errors, and with 0 when it hasn't, even in situations you want to express nothing has happened. In fact, it makes some sense, otherwise the command would break logic chains (like sequelize-cli db:migrate:pending && echo "OK").

Please note that I'm only an enthusiast/contributor, @sdepold is the admin of this repo.

[golmansax]

If that's the case, then maybe it can always exit 0 by default, and then running db:migrate:pending --fail or with some other flag will cause it to exit 1 when then are pending migrations.. Thoughts?

[Americas]

I like this functionality, but the name is probably not the best. #385 has a better idea, and what I would propose is merging this change in that one.

What I propose:

• Create the command db:migrate:status as is in add db:migrate:status #385
• Add 2 optional arguments to that command:
• - --pending outputs only pending migrations
• - --executed outputs only executed migrations

Also, about the exit code, I believe it best to add the --fail flag to tell the program to exit with error on pending migrations. I assume this will be used to programatically chain functionality to the end of this call, it is better to add this as a special use case.

[golmansax]

Yep, that makes sense. Maybe we can put this pull on hold until after #385 is merged, and then I'll update my pull to add onto the db:migrate:status command.

[Americas]

for me that would be perfect 👍

[sushantdhiman]

Closing (PR Cleanup), Open new PR if you wish to continue your work