keg: handle the info directory file properly

If HOMEBREW_KEEP_INFO environment variable is set:
 - Do not symlink the info directory file (aka 'share/info/dir')
   otherwise it gets overwritten by next installed brew.
 - Install an entry in the directory for each linked info file when the
   brew is linked.
 - Uninstall the entry when the brew is unlinked.

Closes Homebrew/homebrew#9700.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/Library/Homebrew/extend/pathname.rb b/Library/Homebrew/extend/pathname.rb
index 4ab94a502..1562bfbcd 100644
--- a/Library/Homebrew/extend/pathname.rb
+++ b/Library/Homebrew/extend/pathname.rb
@@ -262,6 +262,20 @@ class Pathname
   ensure
     chmod saved_perms if saved_perms
   end
+
+  def install_info
+    unless self.symlink?
+      raise "Cannot install info entry for unbrewed info file '#{self}'"
+    end
+    system '/usr/bin/install-info', self.to_s, (self.dirname+'dir').to_s
+  end
+
+  def uninstall_info
+    unless self.symlink?
+      raise "Cannot uninstall info entry for unbrewed info file '#{self}'"
+    end
+    system '/usr/bin/install-info', '--delete', '--quiet', self.to_s, (self.dirname+'dir').to_s
+  end
 end
 
 # sets $n and $d so you can observe creation of stuff
@@ -286,6 +300,14 @@ module ObserverPathnameExtension
     puts "ln #{to_s}" if ARGV.verbose?
     $n+=1
   end
+  def install_info
+    super
+    puts "info #{to_s}" if ARGV.verbose?
+  end
+  def uninstall_info
+    super
+    puts "uninfo #{to_s}" if ARGV.verbose?
+  end
 end
 
 $n=0