(un)linkapps: allow unlink/link specific formulae.

Closes Homebrew/homebrew#35080.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Library/Homebrew/caveats.rb

@@ -97,7 +97,7 @@ class Caveats
     if keg and keg.app_installed?
       <<-EOS.undent
         .app bundles were installed.
-        Run `brew linkapps` to symlink these to /Applications.
+        Run `brew linkapps #{keg.name}` to symlink these to /Applications.
       EOS
     end
   end

Library/Homebrew/cmd/linkapps.rb

@@ -11,12 +11,19 @@ module Homebrew
       exit 1
     end
 
-    HOMEBREW_CELLAR.subdirs.each do |rack|
-      kegs = rack.subdirs.map { |d| Keg.new(d) }
-      next if kegs.empty?
-
-      keg = kegs.detect(&:linked?) || kegs.max {|a,b| a.version <=> b.version}
+    if ARGV.named.empty?
+      racks = HOMEBREW_CELLAR.subdirs
+      kegs = racks.map do |rack|
+        keg = rack.subdirs.map { |d| Keg.new(d) }
+        next if keg.empty?
+        keg.detect(&:linked?) || keg.max {|a,b| a.version <=> b.version}
+      end
+    else
+      kegs = ARGV.kegs
+    end
 
+    kegs.each do |keg|
+      keg = keg.opt_record if keg.optlinked?
       Dir["#{keg}/*.app", "#{keg}/bin/*.app", "#{keg}/libexec/*.app"].each do |app|
         puts "Linking #{app}"
         app_name = File.basename(app)

Library/Homebrew/cmd/unlinkapps.rb

@@ -5,15 +5,11 @@ module Homebrew
   def unlinkapps
     target_dir = ARGV.include?("--local") ? File.expand_path("~/Applications") : "/Applications"
 
-    unless File.exist? target_dir
-      opoo "#{target_dir} does not exist, stopping."
-      puts "Run `mkdir #{target_dir}` first."
-      exit 1
-    end
+    return unless File.exist? target_dir
 
-    cellar_apps = Dir[target_dir + '/*.app'].select do |app|
-      if File.symlink?(app) && File.readlink(app).match(HOMEBREW_CELLAR)
-        File.readlink app
+    cellar_apps = Dir[target_dir + "/*.app"].select do |app|
+      if File.symlink?(app)
+        should_unlink? File.readlink(app)
       end
     end
 
@@ -24,4 +20,14 @@ module Homebrew
 
     puts "Finished unlinking from #{target_dir}" if cellar_apps
   end
+
+  private
+
+  def should_unlink? file
+    if ARGV.named.empty?
+      file.match(HOMEBREW_CELLAR) || file.match("#{HOMEBREW_PREFIX}/opt")
+    else
+      ARGV.kegs.any? { |keg| file.match(keg.to_s) || file.match(keg.opt_record.to_s) }
+    end
+  end
 end

Library/Homebrew/manpages/brew.1.md

@@ -234,11 +234,13 @@ Note that these flags should only appear after a command.
 
     If `--force` is passed, Homebrew will allow keg-only formulae to be linked.
 
-  * `linkapps [--local]`:
-    Find all installed formulae that have compiled `.app`-style "application"
+  * `linkapps [--local] [<formulae>]`:
+    Find installed formulae that have compiled `.app`-style "application"
     packages for OS X, and symlink those apps into `/Applications`, allowing
     for easier access.
 
+    If no <formulae> are provided, all of them will have their .apps symlinked.
+
     If provided, `--local` will move them into the user's `~/Applications`
     folder instead of the system folder. It may need to be created, first.
 
@@ -355,9 +357,11 @@ Note that these flags should only appear after a command.
     for temporarily disabling a formula:
     `brew unlink foo && commands && brew link foo`.
 
-  * `unlinkapps [--local]`:
+  * `unlinkapps [--local] [<formulae>]`:
     Removes links created by `brew linkapps`.
 
+    If no <formulae> are provided, all linked app will be removed.
+
   * `unpack [--git|--patch] [--destdir=<path>]` <formulae>:
 
     Unpack the source files for <formulae> into subdirectories of the current

share/man/man1/brew.1

@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BREW" "1" "November 2014" "Homebrew" "brew"
+.TH "BREW" "1" "December 2014" "Homebrew" "brew"
 .
 .SH "NAME"
 \fBbrew\fR \- The missing package manager for OS X
@@ -251,8 +251,11 @@ If \fB\-\-dry\-run\fR or \fB\-n\fR is passed, Homebrew will list all files which
 If \fB\-\-force\fR is passed, Homebrew will allow keg\-only formulae to be linked\.
 .
 .TP
-\fBlinkapps [\-\-local]\fR
-Find all installed formulae that have compiled \fB\.app\fR\-style "application" packages for OS X, and symlink those apps into \fB/Applications\fR, allowing for easier access\.
+\fBlinkapps [\-\-local] [<formulae>]\fR
+Find installed formulae that have compiled \fB\.app\fR\-style "application" packages for OS X, and symlink those apps into \fB/Applications\fR, allowing for easier access\.
+.
+.IP
+If no \fIformulae\fR are provided, all of them will have their \.apps symlinked\.
 .
 .IP
 If provided, \fB\-\-local\fR will move them into the user\'s \fB~/Applications\fR folder instead of the system folder\. It may need to be created, first\.
@@ -376,9 +379,12 @@ Example: \fBbrew install jruby && brew test jruby\fR
 Remove symlinks for \fIformula\fR from the Homebrew prefix\. This can be useful for temporarily disabling a formula: \fBbrew unlink foo && commands && brew link foo\fR\.
 .
 .TP
-\fBunlinkapps [\-\-local]\fR
+\fBunlinkapps [\-\-local] [<formulae>]\fR
 Removes links created by \fBbrew linkapps\fR\.
 .
+.IP
+If no \fIformulae\fR are provided, all linked app will be removed\.
+.
 .TP
 \fBunpack [\-\-git|\-\-patch] [\-\-destdir=<path>]\fR \fIformulae\fR:
 .