Support loading help_message and version_message from the YAML

src/app/mod.rs

@@ -1467,6 +1467,8 @@ impl<'a> From<&'a Yaml> for App<'a, 'a> {
         yaml_str!(a, yaml, help);
         yaml_str!(a, yaml, help_short);
         yaml_str!(a, yaml, version_short);
+        yaml_str!(a, yaml, help_message);
+        yaml_str!(a, yaml, version_message);
         yaml_str!(a, yaml, alias);
         yaml_str!(a, yaml, visible_alias);
 

tests/app.yml

@@ -4,6 +4,7 @@ about: tests clap library
 author: Kevin K. <kbknapp@gmail.com>
 settings:
     - ArgRequiredElseHelp
+help_message: prints help with a nonstandard description
 args:
     - opt:
         short: o

tests/yaml.rs

@@ -10,3 +10,17 @@ fn create_app_from_yaml() {
     let yml = load_yaml!("app.yml");
     App::from_yaml(yml);
 }
+
+#[test]
+fn help_message() {
+    let yml = load_yaml!("app.yml");
+    let mut app = App::from_yaml(yml);
+    // Generate the full help message!
+    let _ = app.get_matches_from_safe_borrow(Vec::<String>::new());
+
+    let mut help_buffer = Vec::new();
+    app.write_help(&mut help_buffer).unwrap();
+    let help_string = String::from_utf8(help_buffer).unwrap();
+    assert!(help_string.contains(
+        "-h, --help             prints help with a nonstandard description\n"));
+}