Support redirecting standard output using the Command builder - close #28

build_tests/simple/command_redirect.rb

@@ -0,0 +1,8 @@
+Rscons::Environment.new do |env|
+  env.Object("simple.o", "simple.c")
+  env.Command("simple.txt",
+              "simple.o",
+              "CMD" => %w[objdump --disassemble --source ${_SOURCES}],
+              "CMD_STDOUT" => "${_TARGET}",
+              "CMD_DESC" => "My Disassemble")
+end

lib/rscons/builder.rb

@@ -219,11 +219,14 @@ module Rscons
     # @param sources [Array<String>] Source file name(s).
     # @param env [Environment] The Environment executing the builder.
     # @param cache [Cache] The Cache object.
+    # @param options [Hash] Options.
+    # @options options [String] :stdout
+    #   File name to redirect standard output to.
     #
     # @return [String,ThreadedCommand]
     #   The name of the target if it is already up to date or the
     #   {ThreadedCommand} object created to update it.
-    def standard_threaded_build(short_cmd_string, target, command, sources, env, cache)
+    def standard_threaded_build(short_cmd_string, target, command, sources, env, cache, options = {})
       if cache.up_to_date?(target, command, sources, env)
         target
       else
@@ -231,9 +234,11 @@ module Rscons
           cache.mkdir_p(File.dirname(target))
           FileUtils.rm_f(target)
         end
-        ThreadedCommand.new(
-          command,
-          short_description: short_cmd_string)
+        tc_options = {short_description: short_cmd_string}
+        if options[:stdout]
+          tc_options[:system_options] = {out: options[:stdout]}
+        end
+        ThreadedCommand.new(command, tc_options)
       end
     end
 

lib/rscons/builders/command.rb

@@ -25,7 +25,11 @@ module Rscons
         })
         command = env.build_command("${CMD}", vars)
         cmd_desc = vars["CMD_DESC"] || "Command"
-        standard_threaded_build("#{cmd_desc} #{target}", target, command, sources, env, cache)
+        options = {}
+        if vars["CMD_STDOUT"]
+          options[:stdout] = env.expand_varref("${CMD_STDOUT}", vars)
+        end
+        standard_threaded_build("#{cmd_desc} #{target}", target, command, sources, env, cache, options)
       end
 
       # Finalize a build.

spec/build_tests_spec.rb

@@ -748,6 +748,18 @@ EOF
       expect(result.stderr).to eq ""
       expect(result.stdout).to eq ""
     end
+
+    it "allows redirecting standard output to a file" do
+      test_dir("simple")
+
+      result = run_test(rsconsfile: "command_redirect.rb")
+      expect(result.stderr).to eq ""
+      expect(lines(result.stdout)).to eq [
+        "CC simple.o",
+        "My Disassemble simple.txt",
+      ]
+      expect(File.read("simple.txt")).to match /Disassembly of section .text:/
+    end
   end
 
   context "Directory builder" do