Add --output option to redirect diff/patch output to a file of your choice

doc/man/wesnoth.6

@@ -107,7 +107,8 @@ enables some Lua debugging mechanisms
 .BI -D,--diff \ left-file \  right-file
 diffs the two WML files; does not preprocess them first (to do that, run them through
 .B -p
-first). Outputs the diff as DiffWML on standard output.
+first). Outputs the diff as DiffWML on standard output or to the file indicated by
+.IR --output .
 .TP
 .BI -e[ file ],\ --editor[ =file ]
 start the in-game map editor directly. If
@@ -232,6 +233,9 @@ don't try to validate replay of unit test. Only relevant when used with
 .B --nosound
 runs the game without sounds and music.
 .TP
+.BI --output \ file
+output to the specified file. Applicable to diffing operations.
+.TP
 .BI --password \ password
 uses
 .I password
@@ -246,7 +250,8 @@ but Lua file should return a function which will be run as a coroutine and perio
 .TP
 .BI -P,--patch \ base-file \  patch-file
 applies a DiffWML patch to a WML file; does not preprocess either of the files.
-Outputs the patched WML to standard output.
+Outputs the patched WML to standard output or to the file indicated by
+.IR --output .
 .TP
 .BI -p,\ --preprocess \ source-file/folder \  target-directory
 preprocesses a specified file/folder. For each file(s) a plain .cfg file and a processed .cfg

src/commandline_options.cpp

@@ -281,17 +281,18 @@ commandline_options::commandline_options (const std::vector<std::string>& args)
 		("log-strict", po::value<std::string>(), "sets the strict level of the logger. any messages sent to log domains of this level or more severe will cause the unit test to fail regardless of the victory result.")
 		("noreplaycheck", "don't try to validate replay of unit test.")
 		("mp-test", "load the test mp scenarios.")
+		;
+
+	po::options_description parsing_opts("WML parsing options");
+	testing_opts.add_options()
 		("use-schema,S", po::value<std::string>(), "specify a schema to validate WML against (defaults to the core schema)")
 		("validate,V", po::value<std::string>(), "validate a specified WML file against a schema")
 		("validate-addon", po::value<std::string>(), "validate the specified addon's WML against the schema")
 		("validate-core", "validate the core WML against the schema")
 		("validate-schema", po::value<std::string>(), "validate a specified WML schema")
 		("diff,D", po::value<two_strings>()->multitoken(), "diff two preprocessed WML documents")
+		("output,o", po::value<std::string>(), "output to specified file")
 		("patch,P", po::value<two_strings>()->multitoken(), "apply a patch to a preprocessed WML document")
-		;
-
-	po::options_description preprocessor_opts("Preprocessor mode options");
-	preprocessor_opts.add_options()
 		("preprocess,p", po::value<two_strings>()->multitoken(), "requires two arguments: <file/folder> <target directory>. Preprocesses a specified file/folder. The preprocessed file(s) will be written in the specified target directory: a plain cfg file and a processed cfg file.")
 		("preprocess-defines", po::value<std::string>(), "comma separated list of defines to be used by '--preprocess' command. If 'SKIP_CORE' is in the define list the data/core won't be preprocessed. Example: --preprocess-defines=FOO,BAR")
 		("preprocess-input-macros", po::value<std::string>(), "used only by the '--preprocess' command. Specifies source file <arg> that contains [preproc_define]s to be included before preprocessing.")
@@ -310,7 +311,7 @@ commandline_options::commandline_options (const std::vector<std::string>& args)
 	//hidden_.add_options()
 	//	("example-hidden-option", "")
 	//	;
-	visible_.add(general_opts).add(campaign_opts).add(display_opts).add(logging_opts).add(multiplayer_opts).add(testing_opts).add(preprocessor_opts).add(proxy_opts);
+	visible_.add(general_opts).add(campaign_opts).add(display_opts).add(logging_opts).add(multiplayer_opts).add(testing_opts).add(parsing_opts).add(proxy_opts);
 
 	all_.add(visible_).add(hidden_);
 
@@ -447,6 +448,10 @@ commandline_options::commandline_options (const std::vector<std::string>& args)
 		diff_left = vm["patch"].as<two_strings>().first;
 		diff_right = vm["patch"].as<two_strings>().second;
 	}
+	if (vm.count("output"))
+	{
+		output_file = vm["output"].as<std::string>();
+	}
 	if (vm.count("preprocess-defines"))
 		preprocess_defines = utils::split(vm["preprocess-defines"].as<std::string>(), ',');
 	if (vm.count("preprocess-input-macros"))

src/commandline_options.hpp

@@ -215,6 +215,8 @@ public:
 	boost::optional<std::string> validate_wml;
 	/// Non-empty if --use-schema was given on the command line. Specifies the schema for use with --validate.
 	boost::optional<std::string> validate_with;
+	/// Output filename for WML diff or preprocessing
+	boost::optional<std::string> output_file;
 	bool do_diff, do_patch;
 	/// Files for diffing or patching
 	std::string diff_left, diff_right;

src/wesnoth.cpp

@@ -510,8 +510,13 @@ static int process_command_args(const commandline_options& cmdline_opts)
 		std::ifstream in_right(cmdline_opts.diff_right);
 		read(left, in_left);
 		read(right, in_right);
-		config_writer out(std::cout, compression::format::NONE);
+		std::ostream* os = &std::cout;
+		if(cmdline_opts.output_file) {
+			os = new std::ofstream(*cmdline_opts.output_file);
+		}
+		config_writer out(*os, compression::format::NONE);
 		out.write(right.get_diff(left));
+		if(os != &std::cout) delete os;
 		return 0;
 	}
 	
@@ -522,8 +527,13 @@ static int process_command_args(const commandline_options& cmdline_opts)
 		read(base, in_base);
 		read(diff, in_diff);
 		base.apply_diff(diff);
-		config_writer out(std::cout, compression::format::NONE);
+		std::ostream* os = &std::cout;
+		if(cmdline_opts.output_file) {
+			os = new std::ofstream(*cmdline_opts.output_file);
+		}
+		config_writer out(*os, compression::format::NONE);
 		out.write(base);
+		if(os != &std::cout) delete os;
 		return 0;
 	}