Fix downgrading packages.

Boxen is quite insistent about what versions it wants to be installed.
If the version installed does not exactly match the version it wants
it's going to try to `upgrade` to it. Unfortunately Homebrew doesn't
allow `brew upgrade` to downgrade software so the two contradict.

Instead of relying on `brew upgrade` instead just `brew unlink` first
which lets you install (and link) whatever version you want. It also
let's us kill even more Boxen-specific code.

Author: MikeMcQuaid

files/brew-boxen-upgrade.rb

@@ -65,23 +65,22 @@ def install
       # If the desired version is already installed, just link or
       # switch. Somebody might've activated another version for
       # testing or something like that.
-
       execute [ "brew", "switch", @resource[:name], version ], command_opts
-
-    elsif self.class.current @resource[:name]
-      # Okay, so there's a version already active, it's not the right
-      # one, and the right one isn't installed. That's an upgrade.
-
-      execute [ "brew", "boxen-upgrade", @resource[:name] ], command_opts
     else
-      # Nothing here? Nothing from before? Yay! It's a normal install.
+      if self.class.current @resource[:name]
+        # Okay, so there's a version already active, it's not the right
+        # one, and the right one isn't installed. That's an upgrade/downgrade.
+        # However, if we use `brew upgrade` then it won't let us downgrade so
+        # instead let's `brew unlink` and then we're allowed to `brew install`
+        # whatever version we want.
+        execute [ "brew", "unlink", @resource[:name] ], command_opts
+      end
 
       if install_options.any?
         execute [ "brew", "install", @resource[:name], *install_options ].flatten, command_opts
       else
         execute [ "brew", "boxen-install", @resource[:name] ], command_opts
       end
-
     end
   end
 

lib/puppet/provider/package/homebrew.rb

@@ -103,8 +103,6 @@
       source  => 'puppet:///modules/homebrew/brew-boxen-latest.rb' ;
     "${brewsdir}/cmd/brew-boxen-install.rb":
       source  => 'puppet:///modules/homebrew/brew-boxen-install.rb' ;
-    "${brewsdir}/cmd/brew-boxen-upgrade.rb":
-      source  => 'puppet:///modules/homebrew/brew-boxen-upgrade.rb' ;
   }
 
   ->
@@ -114,6 +112,7 @@
       "${boxen::config::envdir}/30_homebrew.sh",
       "${boxen::config::envdir}/cflags.sh",
       "${boxen::config::envdir}/ldflags.sh",
+      "${brewsdir}/cmd/brew-boxen-upgrade.rb",
     ]:
       ensure => absent,
   }

manifests/init.pp

@@ -23,7 +23,7 @@
     should contain_file("#{cmddir}/boxen-bottle-hooks.rb").
       with_source("puppet:///modules/homebrew/boxen-bottle-hooks.rb")
 
-    ["latest", "install", "upgrade"].each do |cmd|
+    ["latest", "install"].each do |cmd|
       should contain_file("#{cmddir}/brew-boxen-#{cmd}.rb").
         with_source("puppet:///modules/homebrew/brew-boxen-#{cmd}.rb")
     end