Extract compute_and_install_dependencies

Library/Homebrew/formula_installer.rb

@@ -102,11 +102,7 @@ class FormulaInstaller
 
     check_conflicts
 
-    unless ignore_deps
+    compute_and_install_dependencies unless ignore_deps
-      perform_readline_hack
-      check_requirements
-      install_dependencies
-    end
 
     if ARGV.build_bottle? && (arch = ARGV.bottle_arch) && !Hardware::CPU.optimization_flags.include?(arch)
       raise "Unrecognized architecture for --bottle-arch: #{arch}"
@@ -141,10 +137,7 @@ class FormulaInstaller
     build_bottle_preinstall if ARGV.build_bottle?
 
     unless @poured_bottle
-      if @pour_failed and not ignore_deps
+      compute_and_install_dependencies if @pour_failed and not ignore_deps
-        check_requirements
-        install_dependencies
-      end
       build
       clean
     end
@@ -179,6 +172,12 @@ class FormulaInstaller
     raise FormulaConflictError.new(f, conflicts) unless conflicts.empty?
   end
 
+  def compute_and_install_dependencies
+    perform_readline_hack
+    check_requirements
+    install_dependencies
+  end
+
   def check_requirements
     unsatisfied = ARGV.filter_for_dependencies do
       f.recursive_requirements do |dependent, req|