v1.2.0

README.md

@@ -110,6 +110,29 @@ Rscons::Environment.new do |env|
 end
 ```
 
+### Example: Custom Builder That Generates Multiple Output Files
+
+```ruby
+class CModuleGenerator < Rscons::Builder
+  def run(target, sources, cache, env, vars)
+    c_fname = target
+    h_fname = target.sub(/\.c$/, ".h")
+    cmd = ["generate_c_and_h", sources.first, c_fname, h_fname]
+    unless cache.up_to_date?([c_fname, h_fname], cmd, sources, env)
+      cache.mkdir_p(File.dirname(target))
+      system(cmd)
+      cache.register_build([c_fname, h_fname], cmd, sources, env)
+    end
+    target
+  end
+end
+
+Rscons::Environment.new do |env|
+  env.add_builder(CModuleGenerator.new)
+  env.CModuleGenerator("build/foo.c", "foo_gen.cfg")
+end
+```
+
 ### Example: Custom Builder Using Builder#standard_build()
 
 The `standard_build` method from the `Rscons::Builder` base class can be used
@@ -218,6 +241,17 @@ cloned_env["CPPPATH"] << "three"
 Documentation for the complete Rscons API can be found at
 http://rubydoc.info/github/holtrop/rscons/frames.
 
+## Release Notes
+
+### v1.2.0
+- add :clone option to Environment#clone to control exactly which Environment attributes are cloned
+- allow nil to be passed in to Environment#build_root=
+
+### v1.1.0
+
+- Change Cache#up_to_date?() and #register_build() to accept a single target
+  file or an array of target file names
+
 ## Contributing
 
 1. Fork it

lib/rscons/builders/library.rb

@@ -1,6 +1,6 @@
 module Rscons
   module Builders
-    # A default RScons builder that produces a static library archive.
+    # A default Rscons builder that produces a static library archive.
     class Rscons::Builders::Library < Rscons::Builder
       def default_variables(env)
         {

lib/rscons/builders/object.rb

@@ -1,6 +1,6 @@
 module Rscons
   module Builders
-    # A default RScons builder which knows how to produce an object file from
+    # A default Rscons builder which knows how to produce an object file from
     # various types of source files.
     class Object < Builder
       KNOWN_SUFFIXES = {

lib/rscons/builders/program.rb

@@ -1,6 +1,6 @@
 module Rscons
   module Builders
-    # A default RScons builder that knows how to link object files into an
+    # A default Rscons builder that knows how to link object files into an
     # executable program.
     class Rscons::Builders::Program < Rscons::Builder
       def default_variables(env)

lib/rscons/cache.rb

@@ -85,16 +85,17 @@ module Rscons
       end
     end
 
-    # Check if a target is up to date
-    # @param target [String] The name of the target file.
-    # @param command [Array] The command used to build the target.
+    # Check if target(s) are up to date
+    # @param targets [String, Array] The name(s) of the target file(s).
+    # @param command [String, Array] The command used to build the target.
     # @param deps [Array] List of the target's dependency files.
     # @param env [Environment] The Rscons::Environment.
     # @param options [Hash] Optional options. Can contain the following keys:
     #   :strict_deps::
     #     Only consider a target up to date if its list of dependencies is
     #     exactly equal (including order) to the cached list of dependencies
-    # @return true value if the target is up to date, meaning that:
+    # @return true if the targets are all up to date, meaning that,
+    #   for each target:
     #   - the target exists on disk
     #   - the cache has information for the target
     #   - the target's checksum matches its checksum when it was last built
@@ -104,7 +105,8 @@ module Rscons
     #     exactly equal to those cached
     #   - each cached dependency file's current checksum matches the checksum
     #     stored in the cache file
-    def up_to_date?(target, command, deps, env, options = {})
+    def up_to_date?(targets, command, deps, env, options = {})
+      Array(targets).each do |target|
         # target file must exist on disk
         return false unless File.exists?(target)
 
@@ -137,16 +139,18 @@ module Rscons
         (cached_deps + cached_user_deps).each do |dep_cache|
           return false unless dep_cache[:checksum] == lookup_checksum(dep_cache[:fname])
         end
+      end
 
       true
     end
 
-    # Store cache information about a target built by a builder
-    # @param target [String] The name of the target.
-    # @param command [Array] The command used to build the target.
+    # Store cache information about target(s) built by a builder
+    # @param targets [String, Array] The name of the target(s) built.
+    # @param command [String, Array] The command used to build the target.
     # @param deps [Array] List of dependencies for the target.
     # @param env [Environment] The Rscons::Environment.
-    def register_build(target, command, deps, env)
+    def register_build(targets, command, deps, env)
+      Array(targets).each do |target|
         @cache[:targets][target.encode(__ENCODING__)] = {
           command: command,
           checksum: calculate_checksum(target),
@@ -164,6 +168,7 @@ module Rscons
           end,
         }
       end
+    end
 
     # Return a list of targets that have been built
     def targets

lib/rscons/environment.rb

@@ -2,7 +2,7 @@ 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
@@ -15,7 +15,8 @@ module Rscons
     # 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.
@@ -50,24 +51,53 @@ module Rscons
     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
@@ -246,7 +276,7 @@ module Rscons
 
     # 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.
@@ -294,7 +324,7 @@ module Rscons
     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)

lib/rscons/version.rb

@@ -1,4 +1,4 @@
 module Rscons
   # gem version
-  VERSION = "1.0.0"
+  VERSION = "1.2.0"
 end

spec/build_tests_spec.rb

@@ -220,7 +220,7 @@ describe Rscons do
   it 'allows Ruby classes as custom builders to be used to construct files' do
     test_dir('custom_builder')
     class MySource < Rscons::Builder
-      def run(target, sources, user_deps, cache, env, vars = {})
+      def run(target, sources, cache, env, vars)
         File.open(target, 'w') do |fh|
           fh.puts <<EOF
     #define THE_VALUE 5678
@@ -241,6 +241,39 @@ EOF
     `./program`.should == "The value is 5678\n"
   end
 
+  it 'supports custom builders with multiple targets' do
+    test_dir('custom_builder')
+    class CHGen < Rscons::Builder
+      def run(target, sources, cache, env, vars)
+        c_fname = target
+        h_fname = target.sub(/\.c$/, ".h")
+        unless cache.up_to_date?([c_fname, h_fname], "", sources, env)
+          puts "CHGen #{c_fname}"
+          File.open(c_fname, "w") {|fh| fh.puts "int THE_VALUE = 42;"}
+          File.open(h_fname, "w") {|fh| fh.puts "extern int THE_VALUE;"}
+          cache.register_build([c_fname, h_fname], "", sources, env)
+        end
+        target
+      end
+    end
+
+    env = Rscons::Environment.new do |env|
+      env.add_builder(CHGen.new)
+      env.CHGen("inc.c", ["program.c"])
+      env.Program("program", Dir["*.c"] + ["inc.c"])
+    end
+
+    lines.should == ["CHGen inc.c", "CC program.o", "CC inc.o", "LD program"]
+    File.exists?("inc.c").should be_true
+    File.exists?("inc.h").should be_true
+    `./program`.should == "The value is 42\n"
+
+    File.open("inc.c", "w") {|fh| fh.puts "int THE_VALUE = 33;"}
+    env.process
+    lines.should == ["CHGen inc.c"]
+    `./program`.should == "The value is 42\n"
+  end
+
   it 'allows cloning Environment objects' do
     test_dir('clone_env')
 
@@ -265,6 +298,29 @@ EOF
     ]
   end
 
+  it 'allows cloning all attributes of an Environment object' do
+    test_dir('clone_env')
+
+    env1 = Rscons::Environment.new(echo: :command) do |env|
+      env.build_dir('src', 'build')
+      env['CFLAGS'] = '-O2'
+      env.add_build_hook do |build_op|
+        build_op[:vars]['CPPFLAGS'] = '-DSTRING="Hello"'
+      end
+      env.Program('program', Dir['src/*.c'])
+    end
+
+    env2 = env1.clone(clone: :all) do |env|
+      env.Program('program2', Dir['src/*.c'])
+    end
+
+    lines.should == [
+      %q{gcc -c -o build/program.o -MMD -MF build/program.mf -DSTRING="Hello" -O2 src/program.c},
+      %q{gcc -o program build/program.o},
+      %q{gcc -o program2 build/program.o},
+    ]
+  end
+
   it 'builds a C++ program with one source file' do
     test_dir('simple_cc')
     Rscons::Environment.new do |env|