Add YAML as a config format option

@mustafa89 ;)

src/config.rs

@@ -36,6 +36,10 @@ impl Config {
             Err(error) => Err(error.to_string()),
         }
     }
+
+    pub fn as_yaml(&self) -> Result<String, String> {
+        serde_yaml::to_string(self).map_err(|e| e.to_string())
+    }
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -62,12 +66,15 @@ pub fn read_config(path: &str) -> Result<Config, String> {
 
     let config: Config = match toml::from_str(&content) {
         Ok(c) => c,
-        Err(e) => {
-            return Err(format!(
-                "Error parsing configuration file \"{}\": {}",
-                path, e
-            ))
-        }
+        Err(_) => match serde_yaml::from_str(&content) {
+            Ok(c) => c,
+            Err(e) => {
+                return Err(format!(
+                    "Error parsing configuration file \"{}\": {}",
+                    path, e
+                ))
+            }
+        },
     };
 
     Ok(config)

src/grm/cmd.rs

@@ -61,10 +61,25 @@ pub struct OptionalConfig {
     pub config: Option<String>,
 }
 
+#[derive(clap::ArgEnum, Clone)]
+pub enum ConfigFormat {
+    Yaml,
+    Toml,
+}
+
 #[derive(Parser)]
 pub struct Find {
     #[clap(help = "The path to search through")]
     pub path: String,
+
+    #[clap(
+        arg_enum,
+        short,
+        long,
+        help = "Format to produce",
+        default_value_t = ConfigFormat::Toml,
+    )]
+    pub format: ConfigFormat,
 }
 
 #[derive(Parser)]

src/grm/main.rs

@@ -119,15 +119,34 @@ fn main() {
                 } else {
                     let config = trees.to_config();
 
-                    let toml = match config.as_toml() {
-                        Ok(toml) => toml,
-                        Err(error) => {
-                            print_error(&format!("Failed converting config to TOML: {}", &error));
-                            process::exit(1);
+                    match find.format {
+                        cmd::ConfigFormat::Toml => {
+                            let toml = match config.as_toml() {
+                                Ok(toml) => toml,
+                                Err(error) => {
+                                    print_error(&format!(
+                                        "Failed converting config to TOML: {}",
+                                        &error
+                                    ));
+                                    process::exit(1);
+                                }
+                            };
+                            print!("{}", toml);
                         }
-                    };
-
-                    print!("{}", toml);
+                        cmd::ConfigFormat::Yaml => {
+                            let yaml = match config.as_yaml() {
+                                Ok(yaml) => yaml,
+                                Err(error) => {
+                                    print_error(&format!(
+                                        "Failed converting config to YAML: {}",
+                                        &error
+                                    ));
+                                    process::exit(1);
+                                }
+                            };
+                            print!("{}", yaml);
+                        }
+                    }
                 }
                 for warning in warnings {
                     print_warning(&warning);