Rework builder interface to only use #run method - close #91

The builder's #run method will be called repeatedly until it returns
true or false. The Builder#wait_for method can be used to cause a
builder to wait for a Thread, Command, or another Builder.

build_tests/simple/builder_no_sources.rb

@@ -1,6 +1,6 @@
 class TestBuilder < Rscons::Builder
   def run(options)
-    target
+    true
   end
 end
 build do

build_tests/simple/cache_debugging.rb

@@ -1,30 +1,30 @@
 class DebugBuilder < Rscons::Builder
   def run(options)
-    command = %W[gcc -c -o #{@target} #{@sources.first}]
-    if Rscons.vars["command_change"]
-      command += %w[-Wall]
-    end
-    if Rscons.vars["new_dep"]
-      @sources += ["extra"]
-    end
-    if Rscons.vars["strict_deps1"]
-      @sources += ["extra"]
-      strict_deps = true
-    end
-    if Rscons.vars["strict_deps2"]
-      @sources = ["extra"] + @sources
-      strict_deps = true
-    end
-    if @cache.up_to_date?(@target, command, @sources, @env, debug: true, strict_deps: strict_deps)
-      @target
+    if @command
+      finalize_command
     else
-      ThreadedCommand.new(command, short_description: "#{name} #{@target}")
+      @command = %W[gcc -c -o #{@target} #{@sources.first}]
+      if Rscons.vars["command_change"]
+        @command += %w[-Wall]
+      end
+      if Rscons.vars["new_dep"]
+        @sources += ["extra"]
+      end
+      if Rscons.vars["strict_deps1"]
+        @sources += ["extra"]
+        strict_deps = true
+      end
+      if Rscons.vars["strict_deps2"]
+        @sources = ["extra"] + @sources
+        strict_deps = true
+      end
+      if @cache.up_to_date?(@target, @command, @sources, @env, debug: true, strict_deps: strict_deps)
+        true
+      else
+        register_command("#{name} #{target}", @command)
+      end
     end
   end
-
-  def finalize(options)
-    standard_finalize(options)
-  end
 end
 
 build do

build_tests/simple/cache_varset.rb

@@ -9,7 +9,7 @@ class TestBuilder < Rscons::Builder
       @env.print_builder_run_message(msg, msg)
       @cache.register_build(@target, command, @sources, @env)
     end
-    @target
+    true
   end
 end
 

build_tests/simple/phony_target.rb

@@ -5,7 +5,7 @@ build do
         puts "Checker #{@sources.first}" if @env.echo != :off
         @cache.register_build(@target, :Checker, @sources, @env)
       end
-      @target
+      true
     end
     env.Program("simple.exe", "simple.c")
     env.Checker(:checker, "simple.exe")

build_tests/simple/threading.rb

@@ -1,12 +1,11 @@
 class ThreadedTestBuilder < Rscons::Builder
   def run(options)
-    command = ["ruby", "-e", %[sleep 1]]
-    Rscons::ThreadedCommand.new(
-      command,
-      short_description: "ThreadedTestBuilder #{@target}")
-  end
-  def finalize(options)
-    true
+    if @command
+      true
+    else
+      @command = ["ruby", "-e", %[sleep 1]]
+      register_command("ThreadedTestBuilder #{@target}", @command)
+    end
   end
 end
 
@@ -14,7 +13,7 @@ class NonThreadedTestBuilder < Rscons::Builder
   def run(options)
     puts "NonThreadedTestBuilder #{@target}"
     sleep 1
-    @target
+    true
   end
 end
 

build_tests/simple/user_dep_build_order.rb

@@ -1,15 +1,15 @@
 class TestBuilder < Rscons::Builder
   def run(options)
-    if @target == "two"
-      return false unless File.exists?("one")
+    if @command
+      true
+    else
+      if @target == "two"
+        return false unless File.exists?("one")
+      end
+      wait_time = @env.expand_varref("${wait_time}", @vars)
+      @command = ["ruby", "-e", "require 'fileutils'; sleep #{wait_time}; FileUtils.touch('#{@target}');"]
+      register_command("TestBuilder", @command)
     end
-    wait_time = @env.expand_varref("${wait_time}", @vars)
-    command = ["ruby", "-e", "require 'fileutils'; sleep #{wait_time}; FileUtils.touch('#{@target}');"]
-    standard_threaded_build("TestBuilder", @target, command, [], @env, @cache)
-  end
-
-  def finalize(options)
-    standard_finalize(options)
   end
 end
 

build_tests/simple/wait_for_builds_on_failure.rb

@@ -1,12 +1,13 @@
 class Fail < Rscons::Builder
   def run(options)
-    wait_time = @env.expand_varref("${wait_time}", @vars)
-    ruby_command = %[sleep #{wait_time}; exit 2]
-    command = %W[ruby -e #{ruby_command}]
-    standard_threaded_build("Fail #{@target}", @target, command, [], @env, @cache)
-  end
-  def finalize(options)
-    standard_finalize(options)
+    if @command
+      finalize_command
+    else
+      wait_time = @env.expand_varref("${wait_time}", @vars)
+      ruby_command = %[sleep #{wait_time}; exit 2]
+      @command = %W[ruby -e #{ruby_command}]
+      register_command("Fail #{@target}", @command)
+    end
   end
 end