Add in_directory directory, to execute commands within a particular path

[jmibanez]

This is similar to Fabric's with cd(path) idiom.

[rstacruz]

Hey JM!

As I mentioned in our chat, this has the minor caveat of these two commands having potentially different results:

# 1:
in_directory('path') {
  queue "a"
  queue "b"
}

# 2:
in_directory('path') { queue "a" }
in_directory('path') { queue "b" }

...because it consolidates all queued commands into one command. One way to fix this would be:

isolated_commands.each do |command|
  queue "(cd #{path} && #{command})"
end

[jmibanez]

Heh. Apparently Github noticed my forced update. Go figure.

[jmibanez]

@rstacruz Hmm... won't the second case above still have the same behavior even with that change?

In the existing commit, we'd get

   (cd path && (a)) &&
   (cd path && (b))

for the second case, while for the change, we'd still get (as I understand it):

   (cd path && (a)) &&
   (cd path && (b))

For the first case, we'd get for the existing:

   (cd path && (a && b))

and with the change

   ((cd path && a) && (cd path && b))

Is my understanding correct?

[rstacruz]

...yes, but if you're using it outside a deploy script, commands are joined with simply semicolons ; in effect. In a deploy script, they're joined using &&. (This is essentially what the deploy do .. end helper does: capture queued commands, join them with '&&', then wrap them inside a boilerplate deploy script.)

Hence, this:

# 0:
task :tail do
   queue "ls"
  queue "tail errors.log"
end


# 1:
task :tail do
  in_directory '/var/www' do
    queue "ls"
    queue "tail errors.log"
  end
end

# 2:
task :tail do
  in_directory('/var/www') { queue "ls" }
  in_directory('/var/www') { queue "tail errors.log" }
end

will become:

# 0:
ls ; tail errors.log

# 1:
cd /var/www && (ls && tail errors.log)

#2:
cd /var/www && (ls)
cd /var/www && (tail errors.log)

[jmibanez]

Ah. That's the missing part. Queuing up another commit.

[rstacruz]

There ya go. You can use gem 'mina', github: 'nadarei/mina' until the next version's released. :)