lib/rscons/environment.rb in rscons-1.1.0 vs lib/rscons/environment.rb in rscons-1.2.0

@@ -1,10 +1,10 @@
 require 'set'
 require 'fileutils'
 
 module Rscons
-  # The Environment class is the main programmatic interface to RScons. It
+  # The Environment class is the main programmatic interface to Rscons. It
   # contains a collection of construction variables, options, builders, and
   # rules for building targets.
   class Environment
     # Hash of +{"builder_name" => builder_object}+ pairs.
     attr_reader :builders
@@ -13,11 +13,12 @@
     attr_accessor :echo
 
     # String or +nil+
     attr_reader :build_root
     def build_root=(build_root)
-      @build_root = build_root.gsub('\\', '/')
+      @build_root = build_root
+      @build_root.gsub!('\\', '/') if @build_root
     end
 
     # Create an Environment object.
     # @param options [Hash]
     # Possible options keys:
@@ -48,28 +49,57 @@
         self.process
       end
     end
 
     # Make a copy of the Environment object.
-    # The cloned environment will contain a copy of all environment options,
-    # construction variables, and builders (unless :exclude_builders => true is
-    # passed as an option). It will not contain a copy of the targets, build
-    # hooks, build directories, or the build root.  If a block is given, the
-    # Environment object is yielded to the block and when the block returns,
-    # the {#process} method is automatically called.  The possible options keys
-    # match those documented in the #initialize method.
+    #
+    # By default, a cloned environment will contain a copy of all environment
+    # options, construction variables, and builders, but not a copy of the
+    # targets, build hooks, build directories, or the build root.
+    #
+    # Exactly which items are cloned are controllable via the optional :clone
+    # parameter, which can be :none, :all, or a set or array of any of the
+    # following:
+    # - :variables to clone construction variables (on by default)
+    # - :builders to clone the builders (on by default)
+    # - :build_root to clone the build root (off by default)
+    # - :build_dirs to clone the build directories (off by default)
+    # - :build_hooks to clone the build hooks (off by default)
+    #
+    # If a block is given, the Environment object is yielded to the block and
+    # when the block returns, the {#process} method is automatically called.
+    #
+    # Any options that #initialize receives can also be specified here.
+    #
+    # @return a new {Environment} object.
     def clone(options = {})
+      clone = options[:clone] || Set[:variables, :builders]
+      clone = Set[:variables, :builders, :build_root, :build_dirs, :build_hooks] if clone == :all
+      clone = Set[] if clone == :none
+      clone = Set.new(clone) if clone.is_a?(Array)
+      clone.delete(:builders) if options[:exclude_builders]
       env = self.class.new(
         echo: options[:echo] || @echo,
         build_root: options[:build_root],
         exclude_builders: true)
-      unless options[:exclude_builders]
+      if clone.include?(:builders)
         @builders.each do |builder_name, builder|
           env.add_builder(builder)
         end
       end
-      env.append(@varset.clone)
+      env.append(@varset.clone) if clone.include?(:variables)
+      env.build_root = @build_root if clone.include?(:build_root)
+      if clone.include?(:build_dirs)
+        @build_dirs.each do |src_dir, obj_dir|
+          env.build_dir(src_dir, obj_dir)
+        end
+      end
+      if clone.include?(:build_hooks)
+        @build_hooks.each do |build_hook_block|
+          env.add_build_hook(&build_hook_block)
+        end
+      end
 
       if block_given?
         yield env
         env.process
       end
@@ -244,11 +274,11 @@
       @user_deps[target]
     end
 
     # Build a list of source files into files containing one of the suffixes
     # given by suffixes.
-    # This method is used internally by RScons builders.
+    # This method is used internally by Rscons builders.
     # @param sources [Array] List of source files to build.
     # @param suffixes [Array] List of suffixes to try to convert source files into.
     # @param cache [Cache] The Cache.
     # @param vars [Hash] Extra variables to pass to the builder.
     # Return a list of the converted file names.
@@ -292,10 +322,10 @@
       end
       builder.run(target, sources, cache, self, vars)
     end
 
     # Parse dependencies for a given target from a Makefile.
-    # This method is used internally by RScons builders.
+    # This method is used internally by Rscons builders.
     # @param mf_fname [String] File name of the Makefile to read.
     # @param target [String] Name of the target to gather dependencies for.
     def self.parse_makefile_deps(mf_fname, target)
       deps = []
       buildup = ''