add Builders::Mixins::ObjectDeps to commonize some builder functionality

lib/rscons/builders/library.rb

@@ -3,17 +3,12 @@ module Rscons
     # A default Rscons builder that produces a static library archive.
     class Library < Builder
 
+      include Mixins::ObjectDeps
+
       # Create an instance of the Builder to build a target.
       def initialize(options)
         super(options)
-        suffixes = @env.expand_varref(["${OBJSUFFIX}", "${LIBSUFFIX}"], @vars)
-        @objects = @sources.map do |source|
-          if source.end_with?(*suffixes)
-            source
-          else
-            @env.register_dependency_build(@target, source, suffixes.first, @vars, Object)
-          end
-        end
+        @objects = register_object_deps(Object)
       end
 
       # Run the builder to produce a build target.

lib/rscons/builders/mixins/object_deps.rb

@@ -0,0 +1,30 @@
+module Rscons
+  module Builders
+    # Rscons::Buidlers::Mixins namespacing module.
+    module Mixins
+      # Functionality for builders which desire object or static library files
+      # as inputs.
+      module ObjectDeps
+
+        # Register dependency builders to generate object files from @sources.
+        #
+        # @param builder_class [Builder]
+        #   Builder class to use to build the object dependencies.
+        #
+        # @return [Array<String>]
+        #   List of paths to the object or static library dependencies.
+        def register_object_deps(builder_class)
+          suffixes = @env.expand_varref(["${OBJSUFFIX}", "${LIBSUFFIX}"], @vars)
+          @sources.map do |source|
+            if source.end_with?(*suffixes)
+              source
+            else
+              @env.register_dependency_build(@target, source, suffixes.first, @vars, builder_class)
+            end
+          end
+        end
+
+      end
+    end
+  end
+end

lib/rscons/builders/program.rb

@@ -4,6 +4,8 @@ module Rscons
     # executable program.
     class Program < Builder
 
+      include Mixins::ObjectDeps
+
       # Create an instance of the Builder to build a target.
       #
       # @param options [Hash]
@@ -21,14 +23,7 @@ module Rscons
         unless File.basename(@target)["."]
           @target += @env.expand_varref("${PROGSUFFIX}", @vars)
         end
-        suffixes = @env.expand_varref(["${OBJSUFFIX}", "${LIBSUFFIX}"], @vars)
-        @objects = @sources.map do |source|
-          if source.end_with?(*suffixes)
-            source
-          else
-            @env.register_dependency_build(@target, source, suffixes.first, @vars, Object)
-          end
-        end
+        @objects = register_object_deps(Object)
       end
 
       # Run the builder to produce a build target.

lib/rscons/builders/shared_library.rb

@@ -4,6 +4,8 @@ module Rscons
     # shared library.
     class SharedLibrary < Builder
 
+      include Mixins::ObjectDeps
+
       # Create an instance of the Builder to build a target.
       def initialize(options)
         super(options)
@@ -14,14 +16,7 @@ module Rscons
         unless File.basename(@target)["."]
           @target += @env.expand_varref("${SHLIBSUFFIX}", @vars)
         end
-        suffixes = @env.expand_varref(["${OBJSUFFIX}", "${LIBSUFFIX}"], @vars)
-        @objects = @sources.map do |source|
-          if source.end_with?(*suffixes)
-            source
-          else
-            @env.register_dependency_build(@target, source, suffixes.first, @vars, SharedObject)
-          end
-        end
+        @objects = register_object_deps(SharedObject)
       end
 
       # Run the builder to produce a build target.