fix(ZSH Completions): fixes bug that caused panic on subcommands with…

… aliases

ZSH completions now fully support subcommands with aliases. Only visible aliases will be displayed
in the completions.

Closes #714

src/app/parser.rs

@@ -1998,7 +1998,7 @@ impl<'a, 'b> Parser<'a, 'b>
         debugln!("Looking for sc...{}", sc);
         debugln!("Currently in Parser...{}", self.meta.bin_name.as_ref().unwrap());
         for s in self.subcommands.iter() {
-            if s.p.meta.bin_name.as_ref().unwrap_or(&String::new()) == sc {
+            if s.p.meta.bin_name.as_ref().unwrap_or(&String::new()) == sc || (s.p.meta.aliases.is_some() && s.p.meta.aliases.as_ref().unwrap().iter().any(|&(s,_)| s == sc.split(' ').rev().next().expect(INTERNAL_ERROR_MSG))) {
                 return Some(s);
             }
             if let Some(app) = s.p.find_subcommand(sc) {

src/completions/zsh.rs

@@ -4,6 +4,7 @@ use std::io::Write;
 use std::ascii::AsciiExt;
 
 // Internal
+use app::App;
 use app::parser::Parser;
 use args::{ArgSettings, AnyArg};
 use completions;
@@ -127,18 +128,26 @@ _{bin_name_underscore}_commands() {{
 fn subcommands_and_args_of(p: &Parser) -> String {
     debugln!("fn=subcommands_and_args_of;");
     let mut ret = vec![];
-
-    // Firs the subcommands
-    for sc in p.subcommands() {
-        debugln!("iter;subcommand={}", sc.p.meta.name);
+    fn add_sc(sc: &App, n: &str, ret: &mut Vec<String>) {
         let s = format!("\"{name}:{help}\" \\", 
-            name = sc.p.meta.name, 
+            name = n, 
             help = sc.p.meta.about.unwrap_or(""));
         if !s.is_empty() {
             ret.push(s);
         }
     }
 
+    // First the subcommands
+    for sc in p.subcommands() {
+        debugln!("iter;subcommand={}", sc.p.meta.name);
+        add_sc(sc, &sc.p.meta.name, &mut ret);
+        if let Some(ref v) = sc.p.meta.aliases {
+            for alias in v.iter().filter(|&&(_, vis)| vis).map(|&(n,_)| n) {
+                add_sc(sc, alias, &mut ret);
+            }
+        }
+    }
+
     // Then the positional args
     for arg in p.positionals() {
         debugln!("iter;arg={}", arg.name);