More modular cmd/install and FormulaInstaller

2 files changed, 103 insertions, 126 deletions

diff --git a/Library/Homebrew/cmd/install.rb b/Library/Homebrew/cmd/install.rb
index ed5fb6777..2c48085da 100644
--- a/Library/Homebrew/cmd/install.rb
+++ b/Library/Homebrew/cmd/install.rb
@@ -3,26 +3,30 @@ require 'hardware'
 
 module Homebrew extend self
   def install
-    brew_install
+    blacklisted? ARGV.named do |msg, name|
+      abort msg
+    end unless ARGV.force?
+
+    install_formulae ARGV.formulae
   end
-end
 
-def brew_install
-  ############################################################ sanity checks
+  def check_ppc
   case Hardware.cpu_type when :ppc, :dunno
     abort "Sorry, Homebrew does not support your computer's CPU architecture.\n"+
           "For PPC support, see: http://github.com/sceaga/homebrew/tree/powerpc"
   end
+  end
 
+  def check_writable_install_location
   raise "Cannot write to #{HOMEBREW_CELLAR}" if HOMEBREW_CELLAR.exist? and not HOMEBREW_CELLAR.writable?
   raise "Cannot write to #{HOMEBREW_PREFIX}" unless HOMEBREW_PREFIX.writable?
+  end
 
-  ################################################################# warnings
-  begin
+  def check_cc
     if MACOS_VERSION >= 10.6
-      opoo "You should upgrade to Xcode 3.2.3" if llvm_build < RECOMMENDED_LLVM
+      opoo "You should upgrade to Xcode 3.2.3" if MacOS.llvm_build_version < RECOMMENDED_LLVM
     else
-      opoo "You should upgrade to Xcode 3.1.4" if (gcc_40_build < RECOMMENDED_GCC_40) or (gcc_42_build < RECOMMENDED_GCC_42)
+      opoo "You should upgrade to Xcode 3.1.4" if (MacOS.gcc_40_build_version < RECOMMENDED_GCC_40) or (MacOS.gcc_42_build_version < RECOMMENDED_GCC_42)
     end
   rescue
     # the reason we don't abort is some formula don't require Xcode
@@ -30,58 +34,69 @@ def brew_install
     opoo "Xcode is not installed! Builds may fail!"
   end
 
-  if macports_or_fink_installed?
-    opoo "It appears you have MacPorts or Fink installed."
-    puts "Software installed with MacPorts and Fink are known to cause problems."
-    puts "If you experience issues try uninstalling these tools."
+  def check_macports
+    if MacOS.macports_or_fink_installed?
+      opoo "It appears you have Macports or Fink installed"
+      puts "Software installed with other package managers causes known problems for"
+      puts "Homebrew. If formula fail to build uninstall Macports/Fink and reinstall any"
+      puts "affected formula."
+    end
   end
 
-  ################################################################# install!
-  installer = FormulaInstaller.new
-  installer.install_deps = !ARGV.include?('--ignore-dependencies')
+  def install_formulae formulae
+    formulae = [formulae].flatten.compact
+    return if formulae.empty?
 
-  ARGV.formulae.each do |f|
-    if not f.installed? or ARGV.force?
-      installer.install f
-    else
-      puts "Formula already installed: #{f.prefix}"
+    check_ppc
+    check_writable_install_location
+    check_cc
+    check_macports
+
+    formulae.each do |f|
+      begin
+        installer = FormulaInstaller.new f
+        installer.ignore_deps = ARGV.include? '--ignore-dependencies'
+        installer.go
+      rescue FormulaAlreadyInstalledError => e
+        opoo e.message
+      end
     end
   end
-end
 
-def check_for_blacklisted_formula names
-  return if ARGV.force?
+  def blacklisted? names
+    names.each do |name|
+      msg = blacklisted_reason name
+      yield msg.undent, name if msg
+    end
+  end
 
-  names.each do |name|
+  def blacklisted_reason name
     case name
-    when 'tex', 'tex-live', 'texlive' then abort <<-EOS.undent
+    when 'tex', 'tex-live', 'texlive' then <<-EOS
       Installing TeX from source is weird and gross, requires a lot of patches,
       and only builds 32-bit (and thus can't use Homebrew deps on Snow Leopard.)
 
       We recommend using a MacTeX distribution:
         http://www.tug.org/mactex/
-    EOS
-
-    when 'mercurial', 'hg' then abort <<-EOS.undent
+      EOS
+    when 'mercurial', 'hg' then <<-EOS
       Mercurial can be install thusly:
         brew install pip && pip install mercurial
-    EOS
-
+      EOS
     when 'npm' then abort <<-EOS.undent
       npm can be installed thusly by following the instructions at
         http://npmjs.org/
 
       To do it in one line, use this command:
         curl http://npmjs.org/install.sh | sudo sh
-    EOS
-
+      EOS
     when 'setuptools' then abort <<-EOS.undent
       When working with a Homebrew-built Python, distribute is preferred
       over setuptools, and can be used as the prerequisite for pip.
 
       Install distribute using:
         brew install distribute
-    EOS
+      EOS
     end
   end
 end
diff --git a/Library/Homebrew/formula_installer.rb b/Library/Homebrew/formula_installer.rb
index 3fceb01b8..06847dfbc 100644
--- a/Library/Homebrew/formula_installer.rb
+++ b/Library/Homebrew/formula_installer.rb
@@ -1,100 +1,57 @@
+require 'exceptions'
 require 'formula'
 require 'set'
 
 class FormulaInstaller
-  @@attempted = Set.new
+  attr :ignore_deps, true
 
-  def initialize
-    @install_deps = true
+  def initialize f
+    @f = f
   end
 
-  attr_writer :install_deps
-
-  def self.expand_deps f
-    deps = []
-    f.deps.collect do |dep|
-      dep = Formula.factory dep
-      deps += expand_deps dep
-      deps << dep
-    end
-    deps
-  end
-
-  def pyerr dep
-    brew_pip = ' brew install pip &&' unless Formula.factory('pip').installed?
-    <<-EOS.undent
-    Unsatisfied dependency, #{dep}
-    Homebrew does not provide Python dependencies, pip does:
-
-        #{brew_pip} pip install #{dep}
-    EOS
-  end
-  def plerr dep; <<-EOS.undent
-    Unsatisfied dependency, #{dep}
-    Homebrew does not provide Perl dependencies, cpan does:
-
-        cpan -i #{dep}
-    EOS
-  end
-  def rberr dep; <<-EOS.undent
-    Unsatisfied dependency "#{dep}"
-    Homebrew does not provide Ruby dependencies, rubygems does:
-
-        gem install #{dep}
-    EOS
-  end
-  def jrberr dep; <<-EOS.undent
-    Unsatisfied dependency "#{dep}"
-    Homebrew does not provide JRuby dependencies, rubygems does:
-
-        jruby -S gem install #{dep}
-    EOS
-  end
-
-  def check_external_deps f
-    return unless f.external_deps
-
-    f.external_deps[:python].each do |dep|
-      raise pyerr(dep) unless quiet_system "/usr/bin/env", "python", "-c", "import #{dep}"
-    end
-    f.external_deps[:perl].each do |dep|
-      raise plerr(dep) unless quiet_system "/usr/bin/env", "perl", "-e", "use #{dep}"
-    end
-    f.external_deps[:ruby].each do |dep|
-      raise rberr(dep) unless quiet_system "/usr/bin/env", "ruby", "-rubygems", "-e", "require '#{dep}'"
-    end
-    f.external_deps[:jruby].each do |dep|
-      raise jrberr(dep) unless quiet_system "/usr/bin/env", "jruby", "-rubygems", "-e", "require '#{dep}'"
+  # raises Homebrew::InstallationErrors in the event of install failures
+  def go
+    if @f.installed? and not ARGV.force?
+      raise FormulaAlreadyInstalledError, @f
+    else
+      unless ignore_deps
+        @f.recursive_deps.each do |dep|
+          FormulaInstaller.install_formula dep unless dep.installed?
+        end
+        FormulaInstaller.check_external_deps @f
+      end
+      FormulaInstaller.install_formula @f
     end
   end
 
-  def check_formula_deps f
-    FormulaInstaller.expand_deps(f).each do |dep|
-      begin
-        install_private dep unless dep.installed?
-      rescue
-        #TODO continue if this is an optional dep
-        raise
-      end
+  def self.check_external_deps f
+    [:ruby, :python, :perl, :jruby].each do |type|
+      f.external_deps[type].each do |dep|
+        unless quiet_system(*external_dep_check(dep, type))
+          raise UnsatisfiedExternalDependencyError.new(dep, type)
+        end
+      end if f.external_deps[type]
     end
   end
 
-  def install f
-    if @install_deps
-      check_external_deps f
-      check_formula_deps f
+  def self.external_dep_check dep, type
+    case type
+      when :python then %W{/usr/bin/env python -c import\ #{dep}}
+      when :jruby then %W{/usr/bin/env jruby -rubygems -e require\ '#{dep}'}
+      when :ruby then %W{/usr/bin/env ruby -rubygems -e require\ '#{dep}'}
+      when :perl then %W{/usr/bin/env perl -e use\ #{dep}}
     end
-    install_private f
   end
 
   private
 
-  def install_private f
-    return if @@attempted.include? f.name
-    @@attempted << f.name
+  def self.install_formula f
+    @attempted ||= Set.new
+    raise FormulaInstallationAlreadyAttemptedError, f if @attempted.include? f
+    @attempted << f
 
     # 1. formulae can modify ENV, so we must ensure that each
-    #    installation has a pristine ENV when it starts, forking now is 
+    #    installation has a pristine ENV when it starts, forking now is
     #    the easiest way to do this
     # 2. formulae have access to __END__ the only way to allow this is
     #    to make the formula script the executed script
@@ -102,24 +59,29 @@ class FormulaInstaller
     # I'm guessing this is not a good way to do this, but I'm no UNIX guru
     ENV['HOMEBREW_ERROR_PIPE'] = write.to_i.to_s
 
-     begin #watch_out_for_spill do #disabled temporarily, see Issue #124
-      fork do
-        begin
-          read.close
-          exec '/usr/bin/nice', '/usr/bin/ruby', '-I', File.dirname(__FILE__), '-rinstall', f.path, '--', *ARGV.options_only
-        rescue => e
-          Marshal.dump(e, write)
-          write.close
-          exit! 1
-        end
-      end
-      ignore_interrupts do # because child proc will get it and marshall it back
+    fork do
+      begin
+        read.close
+        exec '/usr/bin/nice',
+             '/usr/bin/ruby',
+             '-I', Pathname.new(__FILE__).dirname,
+             '-rinstall',
+             f.path,
+             '--',
+             *ARGV.options_only
+      rescue Exception => e
+        Marshal.dump(e, write)
         write.close
-        Process.wait
-        data = read.read
-        raise Marshal.load(data) unless data.nil? or data.empty?
-        raise "Suspicious installation failure" unless $?.success?
+        exit! 1
       end
     end
+
+    ignore_interrupts do # the fork will receive the interrupt and marshall it back
+      write.close
+      Process.wait
+      data = read.read
+      raise Marshal.load(data) unless data.nil? or data.empty?
+      raise "Suspicious installation failure" unless $?.success?
+    end
   end
 end