Dependency resolution

Specify dependencies in your formula's deps function. You can return an Array,
String or Hash, eg:

    def deps
      { :optional => 'libogg', :required => %w[flac sdl], :recommended => 'cmake' }
    end

Note currently the Hash is flattened and qualifications are ignored. If you
only return an Array or String, the qualification is assumed to be :required.

Other packaging systems have problems when it comes to packages requiring a
specific version of a package, or some patches that may not work well with
other software. With Homebrew we have some options:

1.  If the formula is vanilla but an older version we can cherry-pick the old
    version and install it in the Cellar in parallel, but just not symlink it
    into /usr/local while forcing the formula that depends on it to link to
    that one and not any other versions of it.
2.  If the dependency requires patches then we shouldn't install this for use
    by any other tools, (I guess this needs to be decided on a per-situation
    basis). It can be installed into the parent formula's prefix, and not
    symlinked into /usr/local. In this case the dependency's Formula
    derivation should be saved in the parent formula's file (check git or
    flac for an example of this).

Both the above can be done currently with hacks, so I'll flesh out a proper
way sometime this week.

25 files changed, 150 insertions, 116 deletions

diff --git a/Library/Formula/fish.rb b/Library/Formula/fish.rb
index c84bb8111..09246747e 100644
--- a/Library/Formula/fish.rb
+++ b/Library/Formula/fish.rb
@@ -6,7 +6,7 @@ class Fish <Formula
   @md5='4b2436843e63bebba467cc4add11428a'
 
   def deps
-    LibraryDep.new 'readline'
+    'readline'
   end
 
   def install
diff --git a/Library/Formula/ghostscript.rb b/Library/Formula/ghostscript.rb
new file mode 100644
index 000000000..9f7ef7785
--- /dev/null
+++ b/Library/Formula/ghostscript.rb
@@ -0,0 +1,32 @@
+require 'brewkit'
+
+class GhostscriptFonts <Formula
+  @url='http://downloads.sourceforge.net/project/gs-fonts/gs-fonts/8.11%20%28base%2035%2C%20GPL%29/ghostscript-fonts-std-8.11.tar.gz'
+  @homepage='http://sourceforge.net/projects/gs-fonts/'
+  @md5='6865682b095f8c4500c54b285ff05ef6'
+end
+
+class Ghostscript <Formula
+  @url='http://downloads.sourceforge.net/project/ghostscript/GPL%20Ghostscript/8.70/ghostscript-8.70.tar.bz2'
+  @homepage='http://www.ghostscript.com/'
+  @md5='526366f8cb4fda0d3d293597cc5b984b'
+  
+  def install
+    # ghostscript configure ignores LDFLAGs apparently
+    ENV['LIBS']="-L/usr/X11/lib"
+    system "./configure", "--prefix=#{prefix}", "--disable-debug", 
+                          # the cups component adamantly installs to /usr so fuck it
+                          "--disable-cups"
+    # versioned stuff in main tree is pointless for us
+    inreplace 'Makefile', '/$(GS_DOT_VERSION)', ''
+    system "make install"
+    (prefix+'share'+'ghostscript'+'doc').rmtree
+
+    GhostscriptFonts.new.brew do
+      Dir.chdir '..'
+      (prefix+'share'+'ghostscript').install 'fonts'
+    end
+    
+    (man+'de').rmtree
+  end
+end
diff --git a/Library/Formula/imagemagick.rb b/Library/Formula/imagemagick.rb
index 5db518006..ee06a50ac 100644
--- a/Library/Formula/imagemagick.rb
+++ b/Library/Formula/imagemagick.rb
@@ -2,43 +2,13 @@ require 'brewkit'
 
 # some credit to http://github.com/maddox/magick-installer
 
-class LibTIFF <Formula
-  @url='ftp://ftp.remotesensing.org/libtiff/tiff-3.8.2.tar.gz'
-  @homepage='http://www.libtiff.org/'
-  @md5='fbb6f446ea4ed18955e2714934e5b698'
-end
-
-class Libwmf <Formula
-  @url='http://downloads.sourceforge.net/project/wvware/libwmf/0.2.8.4/libwmf-0.2.8.4.tar.gz'
-  @homepage='http://wvware.sourceforge.net/libwmf.html'
-  @md5='d1177739bf1ceb07f57421f0cee191e0'
-end
-
-class LittleCMS <Formula
-  @url='http://www.littlecms.com/lcms-1.17.tar.gz'
-  @homepage='http://www.littlecms.com/'
-  @md5='07bdbb4cfb05d21caa58fe3d1c84ddc1'
-end
-
-class Ghostscript <Formula
-  @url='http://downloads.sourceforge.net/project/ghostscript/GPL%20Ghostscript/8.70/ghostscript-8.70.tar.bz2'
-  @homepage='http://www.ghostscript.com/'
-  @md5='526366f8cb4fda0d3d293597cc5b984b'
-end
-
-class GhostscriptFonts <Formula
-  @url='http://downloads.sourceforge.net/project/gs-fonts/gs-fonts/8.11%20%28base%2035%2C%20GPL%29/ghostscript-fonts-std-8.11.tar.gz'
-  @homepage='http://sourceforge.net/projects/gs-fonts/'
-  @md5='6865682b095f8c4500c54b285ff05ef6'
-end
-
 class Imagemagick <Formula
   @url='ftp://ftp.imagemagick.org/pub/ImageMagick/ImageMagick-6.5.5-4.tar.bz2'
   @md5='8cb7471a50428e4892ee46aa404e54c2'
   @homepage='http://www.imagemagick.org'
 
   def deps
-    LibraryDep.new 'jpeg'
+    { :required => 'jpeg', :optional => %w[libwmf libtiff little-cms ghostscript] }
   end
 
   def install
@@ -47,33 +17,6 @@ class Imagemagick <Formula
 
     # TODO eventually these will be external optional dependencies
     # but for now I am lazy
-    LibTIFF.new.brew do
-      system "./configure", "--prefix=#{prefix}", "--disable-debug"
-      system "make install"
-    end
-    Libwmf.new.brew do
-      system "./configure", "--prefix=#{prefix}", "--disable-debug"
-      system "make install"
-    end
-    LittleCMS.new.brew do
-      system "./configure", "--prefix=#{prefix}", "--disable-debug"
-      system "make install"
-    end
-    Ghostscript.new.brew do
-      # ghostscript configure ignores LDFLAGs apparently
-      ENV['LIBS']="-L/usr/X11/lib"
-      system "./configure", "--prefix=#{prefix}", "--disable-debug", 
-                            # the cups component adamantly installs to /usr so fuck it
-                            "--disable-cups"
-      # versioned stuff in main tree is pointless for us
-      inreplace 'Makefile', '/$(GS_DOT_VERSION)', ''
-      system "make install"
-      (prefix+'share'+'ghostscript'+'doc').rmtree
-    end
-    GhostscriptFonts.new.brew do
-      Dir.chdir '..'
-      (prefix+'share'+'ghostscript').install 'fonts'
-    end
 
     # versioned stuff in main tree is pointless for us
     inreplace 'configure', '${PACKAGE_NAME}-${PACKAGE_VERSION}', '${PACKAGE_NAME}'
@@ -91,8 +34,6 @@ class Imagemagick <Formula
     (d+'NEWS.txt').unlink
     (d+'LICENSE').unlink
     (d+'ChangeLog').unlink
-    
-    (man+'de').rmtree
   end
 
   def caveats
diff --git a/Library/Formula/liblastfm.rb b/Library/Formula/liblastfm.rb
index 52444bdfa..ea6a61706 100644
--- a/Library/Formula/liblastfm.rb
+++ b/Library/Formula/liblastfm.rb
@@ -6,9 +6,7 @@ class Liblastfm <Formula
   @md5='3f73222ebc31635941832b01e7a494b6'
 
   def deps
-    BinaryDep.new 'qmake', 'qt'
-    LibraryDep.new 'fftw3f', 'fftw'
-    LibraryDep.new 'samplerate'
+    %w[qt fftw samplerate]
   end
 
   def install
diff --git a/Library/Formula/libmusicbrainz.rb b/Library/Formula/libmusicbrainz.rb
index d562ab12a..b9d5c1c45 100644
--- a/Library/Formula/libmusicbrainz.rb
+++ b/Library/Formula/libmusicbrainz.rb
@@ -6,8 +6,7 @@ class Libmusicbrainz <Formula
   @md5='648ecd43f7b80852419aaf73702bc23f'
 
   def deps
-    LibraryDep.new 'neon'
-    OptionalLibraryDep.new 'libdiscid'
+    { :required => 'neon', :optional => 'libdiscid' }
   end
 
   def install
diff --git a/Library/Formula/libtiff.rb b/Library/Formula/libtiff.rb
new file mode 100644
index 000000000..831491321
--- /dev/null
+++ b/Library/Formula/libtiff.rb
@@ -0,0 +1,12 @@
+require 'brewkit'
+
+class Libtiff <Formula
+  @url='ftp://ftp.remotesensing.org/libtiff/tiff-3.8.2.tar.gz'
+  @homepage='http://www.libtiff.org/'
+  @md5='fbb6f446ea4ed18955e2714934e5b698'
+
+  def install
+    system "./configure", "--prefix=#{prefix}", "--disable-debug"
+    system "make install"
+  end
+end
diff --git a/Library/Formula/libvorbis.rb b/Library/Formula/libvorbis.rb
index d597b1feb..cdd795437 100644
--- a/Library/Formula/libvorbis.rb
+++ b/Library/Formula/libvorbis.rb
@@ -6,7 +6,7 @@ class Libvorbis <Formula
   @homepage='http://vorbis.com'
 
   def deps
-    LibraryDep.new 'libogg'
+    'libogg'
   end
 
   def install
diff --git a/Library/Formula/libwmf.rb b/Library/Formula/libwmf.rb
new file mode 100644
index 000000000..f1a3ba1a1
--- /dev/null
+++ b/Library/Formula/libwmf.rb
@@ -0,0 +1,16 @@
+require 'brewkit'
+
+class Libwmf <Formula
+  @url='http://downloads.sourceforge.net/project/wvware/libwmf/0.2.8.4/libwmf-0.2.8.4.tar.gz'
+  @homepage='http://wvware.sourceforge.net/libwmf.html'
+  @md5='d1177739bf1ceb07f57421f0cee191e0'
+
+  def install
+    ENV.libpng
+    system "./configure", "--prefix=#{prefix}", "--disable-debug"
+    system "make"
+
+    ENV.j1 # yet another rubbish Makefile
+    system "make install"
+  end
+end
diff --git a/Library/Formula/little-cms.rb b/Library/Formula/little-cms.rb
new file mode 100644
index 000000000..a3efd783b
--- /dev/null
+++ b/Library/Formula/little-cms.rb
@@ -0,0 +1,12 @@
+require 'brewkit'
+
+class LittleCms <Formula
+  @url='http://www.littlecms.com/lcms-1.17.tar.gz'
+  @homepage='http://www.littlecms.com/'
+  @md5='07bdbb4cfb05d21caa58fe3d1c84ddc1'
+
+  def install
+    system "./configure", "--prefix=#{prefix}", "--disable-debug"
+    system "make install"
+  end
+end
diff --git a/Library/Formula/memcached.rb b/Library/Formula/memcached.rb
index fda521f1d..0ad5681c3 100644
--- a/Library/Formula/memcached.rb
+++ b/Library/Formula/memcached.rb
@@ -6,7 +6,7 @@ class Memcached <Formula
   @md5='d7651ecb8bf345144cb17900d9a46c85'
 
   def deps
-    LibraryDep.new 'libevent'
+    'libevent'
   end
 
   def install
diff --git a/Library/Formula/mysql-connector-c.rb b/Library/Formula/mysql-connector-c.rb
index f97945135..f135f7dc8 100644
--- a/Library/Formula/mysql-connector-c.rb
+++ b/Library/Formula/mysql-connector-c.rb
@@ -6,7 +6,7 @@ class MysqlConnectorC <Formula
   @md5='348a869fa72957062ea4e7ad3865623c'
 
   def deps
-    BinaryDep.new 'cmake'
+    'cmake'
   end
 
   def install
diff --git a/Library/Formula/mysql.rb b/Library/Formula/mysql.rb
index 662d8320d..5cfb8be41 100644
--- a/Library/Formula/mysql.rb
+++ b/Library/Formula/mysql.rb
@@ -6,8 +6,7 @@ class Mysql <Formula
   @md5='7564d7759a8077b3a0e6190955422287'
 
   def deps
-    # --without-readline means use system's readline
-    LibraryDep.new 'readline'
+    'readline'
   end
 
   def options
diff --git a/Library/Formula/nginx.rb b/Library/Formula/nginx.rb
index b2fe3e2fa..4863381e6 100644
--- a/Library/Formula/nginx.rb
+++ b/Library/Formula/nginx.rb
@@ -6,7 +6,7 @@ class Nginx <Formula
   @md5='6ebf89b9b00a3b82734e93c32da7df07'
 
   def deps
-    LibraryDep.new 'pcre'
+    'pcre'
   end
     
   def install
diff --git a/Library/Formula/playdar.rb b/Library/Formula/playdar.rb
index 0d2669ea8..44b1f815d 100644
--- a/Library/Formula/playdar.rb
+++ b/Library/Formula/playdar.rb
@@ -5,9 +5,7 @@ class Playdar <Formula
   @head='git://github.com/mxcl/playdar.git'
 
   def deps
-    LibraryDep.new 'taglib'
-    LibraryDep.new 'boost'
-    BinaryDep.new 'cmake'
+    %w[taglib boost cmake]
   end
 
   def skip_clean? path
diff --git a/Library/Formula/python.rb b/Library/Formula/python.rb
index d1d058644..0624146bc 100644
--- a/Library/Formula/python.rb
+++ b/Library/Formula/python.rb
@@ -7,7 +7,7 @@ class Python <Formula
 
   def deps
     # You can build Python without readline, but you really don't want to.
-    LibraryDep.new 'readline'
+    'readline'
   end
   
   def skip_clean? path
diff --git a/Library/Formula/scummvm.rb b/Library/Formula/scummvm.rb
index de0bd7bf1..adb1f1a48 100644
--- a/Library/Formula/scummvm.rb
+++ b/Library/Formula/scummvm.rb
@@ -14,11 +14,7 @@ prefer to use theirs. If so type `brew home scummvm' to visit their site.
   end
 
   def deps
-    LibraryDep.new 'sdl'
-    # Optional, but you want them anyway.
-    OptionalLibraryDep.new 'flac'
-    OptionalLibraryDep.new 'libogg'
-    OptionalLibraryDep.new 'libvorbis'
+    { :required => 'sdl', :recommended => %w[flac libogg libvorbis] }
   end
 
   def install
diff --git a/Library/Formula/sshfs.rb b/Library/Formula/sshfs.rb
index 67d94fae4..0ae3f40d9 100644
--- a/Library/Formula/sshfs.rb
+++ b/Library/Formula/sshfs.rb
@@ -14,9 +14,7 @@ class Sshfs <Formula
   end
 
   def deps
-    BinaryDep.new 'pkg-config'
-    LibraryDep.new 'glib'
-    LibraryDep.new 'macfuse'
+    %w[pkg-config glib macfuse]
   end
 
   def install
diff --git a/Library/Formula/taglib.rb b/Library/Formula/taglib.rb
index 59129a16a..ea92fa6df 100644
--- a/Library/Formula/taglib.rb
+++ b/Library/Formula/taglib.rb
@@ -11,13 +11,13 @@ class Taglib <Formula
   @homepage='http://developer.kde.org/~wheeler/taglib.html'
 
   def deps
-    BinaryDep.new 'cmake'
+    'cmake'
   end
 
   def install
     system "./configure --disable-debug --prefix='#{prefix}'"
     system "make install"
-    
+
     TaglibExtras.new.brew do
       system "cmake . #{std_cmake_parameters}"
       system "make install"
diff --git a/Library/Formula/unp.rb b/Library/Formula/unp.rb
index 50ab9ea8c..83cd639c2 100644
--- a/Library/Formula/unp.rb
+++ b/Library/Formula/unp.rb
@@ -6,7 +6,7 @@ class Unp <Formula
   @md5='ecea662bd7e7efe7f7e2213bf21d9646'
 
  def deps
-   BinaryDep.new 'p7zip'
+   'p7zip'
  end
 
   def install
diff --git a/Library/Formula/vorbis-tools.rb b/Library/Formula/vorbis-tools.rb
index 4cd6613ac..b057cbe18 100644
--- a/Library/Formula/vorbis-tools.rb
+++ b/Library/Formula/vorbis-tools.rb
@@ -6,9 +6,7 @@ class VorbisTools <Formula
   @homepage='http://vorbis.com'
 
   def deps
-    LibraryDep.new 'ogg'
-    LibraryDep.new 'vorbis'
-    OptionalLibraryDep.new 'ao', 'ogg123'
+    { :required => %w[ogg vorbis], :optional => %w[ao ogg123] }
   end
 
   def install
diff --git a/Library/Formula/yajl.rb b/Library/Formula/yajl.rb
index 288e2fd39..19f47f2ff 100644
--- a/Library/Formula/yajl.rb
+++ b/Library/Formula/yajl.rb
@@ -6,7 +6,7 @@ class Yajl <Formula
   @md5='f4a3cbc764c43231ed1aedc54438b69b'
 
   def deps
-    BinaryDep.new 'cmake'
+    'cmake'
   end
 
   def install
@@ -18,4 +18,4 @@ class Yajl <Formula
     system "./configure --prefix '#{prefix}'"
     system "make install"
   end
-end
\ No newline at end of file
+end
diff --git a/Library/Homebrew/brew.h.rb b/Library/Homebrew/brew.h.rb
index 8b3939968..496e7afc0 100644
--- a/Library/Homebrew/brew.h.rb
+++ b/Library/Homebrew/brew.h.rb
@@ -144,6 +144,33 @@ def clean f
 end
 
 
+# NOTE this is ugly code, and inefficient too, and can have infinite cycles
+# I have no time currently to improve it, feel free to submit a more elegant
+# solution. Thanks! --mxcl
+def expand_deps fae
+  deps = []
+  fae.each do |f|
+    case f.deps
+    when String, Array
+      f.deps.each do |name|
+        f = Formula.factory name
+        deps << expand_deps(f) if f.deps # hideous inefficient
+        deps << f
+      end
+    when Hash
+      # TODO implement optional and recommended
+      names = []
+      f.deps.each_value {|v| names << v}
+      ff=names.flatten.collect {|name| Formula.factory name}
+      deps << expand_deps(ff)
+    end
+    deps << f
+  end
+  # TODO much more efficient to use a set and not recurse stuff already done
+  return deps.flatten.uniq
+end
+
+
 def install f
   f.brew do
     if ARGV.flag? '--interactive'
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 7faabbae6..9c5123545 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -123,7 +123,7 @@ class Formula
   def brew
     validate_variable :name
     validate_variable :version
-    
+
     stage do
       begin
         patch
diff --git a/Library/Homebrew/unittest.rb b/Library/Homebrew/unittest.rb
index ae8b0c1bc..2738755e4 100755
--- a/Library/Homebrew/unittest.rb
+++ b/Library/Homebrew/unittest.rb
@@ -41,7 +41,8 @@ class MostlyAbstractFormula <Formula
 end
 
 class TestBall <Formula
-  def initialize
+  # name parameter required for some Formula::factory
+  def initialize name=nil
     @url="file:///#{Pathname.new(ABS__FILE__).parent.realpath}/testball-0.1.tbz"
     super "testball"
   end
@@ -98,9 +99,13 @@ def nostdout
 end
 
 module ExtendArgvPlusYeast
-  def stick_an_arg_in_thar
+  def reset
     @named=nil
-    unshift 'foo'
+    @formulae=nil
+    @kegs=nil
+    while ARGV.count > 0
+      ARGV.shift
+    end
   end
 end
 ARGV.extend ExtendArgvPlusYeast
@@ -347,8 +352,9 @@ class BeerTasting <Test::Unit::TestCase
   end
 
   def test_no_ARGV_dupes
-    ARGV.unshift'foo'
-    ARGV.unshift'foo'
+    ARGV.reset
+    ARGV.unshift 'foo'
+    ARGV.unshift 'foo'
     n=0
     ARGV.named.each{|arg| n+=1 if arg == 'foo'}
     assert_equal 1, n
@@ -360,9 +366,10 @@ class BeerTasting <Test::Unit::TestCase
     assert_raises(UsageError) { ARGV.kegs }
     assert ARGV.named_empty?
     
-    (HOMEBREW_CELLAR+'foo'+'0.1').mkpath
+    (HOMEBREW_CELLAR+'mxcl'+'10.0').mkpath
     
-    ARGV.stick_an_arg_in_thar
+    ARGV.reset
+    ARGV.unshift 'mxcl'
     assert_equal 1, ARGV.named.length
     assert_equal 1, ARGV.kegs.length
     assert_raises(FormulaUnavailableError) { ARGV.formulae }
@@ -395,7 +402,7 @@ class BeerTasting <Test::Unit::TestCase
     nostdout do
       assert_nothing_raised do
         f=TestBall.new
-        make 'http://example.com/testball-0.1.tbz'
+        make f.url
         info f.name
         clean f
         prune
diff --git a/bin/brew b/bin/brew
index ba7080290..6ce18a4ac 100755
--- a/bin/brew
+++ b/bin/brew
@@ -95,20 +95,24 @@ begin
         raise "We cannot find a c compiler, have you installed the latest Xcode?"
       end
 
-      require 'beer_events'
-      
-      watch_out_for_spill do
-        ARGV.formulae.each do |f|
-          if f.installed? and not ARGV.force?
-            message = "Formula already installed: #{f.prefix}"
-            if ARGV.formulae.count > 1
-              opoo message
-            else
-              puts message # if only one is being installed a warning looks severe
-            end
-            next
+      fae = ARGV.formulae.reject do |f|
+        if f.installed? and not ARGV.force?
+          message = "Formula already installed: #{f.prefix}"
+          if ARGV.formulae.count > 1
+            opoo message
+          else
+            puts message # if only one is being installed a warning looks severe
           end
+          true
+        end
+      end
+
+      fae=expand_deps ARGV.formulae
 
+      require 'beer_events'
+
+      watch_out_for_spill do
+        fae.each do |f|
           # we need to ensure a pristine ENV for each process or the formula
           # will start with the ENV from the previous build
           pid=fork
@@ -162,9 +166,6 @@ begin
     when 'unlink'
       ARGV.kegs.each {|keg| puts "#{keg.unlink} links removed for #{keg}"}
 
-    when 'unlink'
-      ARGV.kegs.each {|keg| puts "#{keg.unlink} links removed for #{keg}"}
-
     when 'rm', 'uninstall', 'remove'
       ARGV.kegs.each do |keg|
         puts "Uninstalling #{keg}..."