Add `-h` argument

Print usage on `-h` and `--help`.

Store the usage brief on `Config` in order to be able to print it from
multiple places.

3 files changed, 21 insertions, 11 deletions

diff --git a/src/bin/git-sugpatch.rs b/src/bin/git-sugpatch.rs
index c8fc0a8..10499e9 100644
--- a/src/bin/git-sugpatch.rs
+++ b/src/bin/git-sugpatch.rs
@@ -10,7 +10,10 @@ use github_suggestion_cli::config::Config;
 fn main() {
     let args: Vec<_> = env::args().collect();
 
-    let config = match Config::get(&args) {
+    let config = match Config::get(
+        &args,
+        "usage: git sugpatch [options] <suggestion>...",
+    ) {
         Ok(c) => c,
         Err(e) => {
             gseprintln!(e);
@@ -20,10 +23,7 @@ fn main() {
     };
 
     if config.suggestions.is_empty() {
-        print!(
-            "{}",
-            config.usage("usage: git sugpatch [options] <suggestion>..."),
-        );
+        config.print_usage();
 
         process::exit(exitcode::USAGE);
     }
diff --git a/src/config.rs b/src/config.rs
index 4402014..476b597 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,4 +1,5 @@
 use std::env;
+use std::process;
 
 use getopts::{self, Options};
 use git2::{self, Repository};
@@ -27,23 +28,31 @@ pub enum Error {
     Git(#[from] git2::Error),
 }
 
-pub struct Config {
+pub struct Config<'a> {
     pub github_token: String,
     pub o_r: Result<OwnerRepo, owner_repo::Error>,
     pub suggestions: Vec<String>,
 
     opts: Options,
+    usage_brief: &'a str,
 }
 
-impl Config {
-    pub fn get(args: &[String]) -> Result<Self, Error> {
+impl<'a> Config<'a> {
+    pub fn get(args: &[String], usage_brief: &'a str) -> Result<Self, Error> {
         let mut opts = Options::new();
 
         opts.optopt("", "github-token", "", "TOKEN");
         opts.optopt("", "remote", "", "REMOTE");
+        opts.optflag("h", "help", "print this help menu");
 
         let opt_matches = opts.parse(&args[1..])?;
 
+        if opt_matches.opt_present("h") {
+            print!("{}", opts.usage(&usage_brief));
+
+            process::exit(exitcode::USAGE);
+        }
+
         let git_config = Repository::open(".")?.config()?;
 
         let o_r = OwnerRepo::from_remote(
@@ -56,11 +65,12 @@ impl Config {
             suggestions: opt_matches.free,
 
             opts: opts,
+            usage_brief,
         })
     }
 
-    pub fn usage(&self, brief: &str) -> String {
-        self.opts.usage(&brief)
+    pub fn print_usage(&self) {
+        print!("{}", self.opts.usage(&self.usage_brief))
     }
 
     fn github_token(
diff --git a/src/suggestion.rs b/src/suggestion.rs
index fc22a7c..f1684e0 100644
--- a/src/suggestion.rs
+++ b/src/suggestion.rs
@@ -9,7 +9,7 @@ use crate::arg::is_suggestion_id;
 use crate::config::Config;
 
 
-pub fn for_suggestion<F>(config: &Config, f: F)
+pub fn for_suggestion<F>(config: &Config<'_>, f: F)
 where F: Fn(&Suggestion)
 {
     for suggestion_arg in &config.suggestions {