Add the 'alias' built-in command

The shell now has support for aliases (via alias foo=bar). The 'unalias'
command is also available to remove aliases. Finally,
Environment::aliases was changed to be a HashMap<String, String>,
instead of a Vec<String>.

Since the verse's verb might change (for instance, it is an environment
variable, or an alias), add another check in Poem::recite, which simply
continues, instead of running the spellchecker, if the verb is empty.

1 files changed, 21 insertions, 5 deletions

diff --git a/src/poem/recite.rs b/src/poem/recite.rs
index e37b7c6..9a425e8 100644
--- a/src/poem/recite.rs
+++ b/src/poem/recite.rs
@@ -54,6 +54,18 @@ impl Reciteable for Poem {
                 }
             }
 
+            // Check for aliases
+            match env.aliases.get(&verse.verb()) {
+                Some(verb) => {
+                    let mut split: Vec<String> = verb.split(" ").map(|s| s.to_string()).collect();
+                    let mut old_stanza = verse.stanza.clone();
+                    old_stanza.remove(0);
+                    split.append(&mut old_stanza);
+                    verse.stanza = split;
+                }
+                None => {}
+            };
+
             // Run interal poems
             let v = verse.clone();
             let mut new_stanza = None;
@@ -129,15 +141,19 @@ impl Reciteable for Poem {
                 // If it doesn't exist, try refreshing the binary cache, and check
                 // again
                 // If it still doesn't exist, print an error
-                if !verse.spellcheck(&env.bins) {
-                    env.bins = path::refresh();
+                if !verse.verb().is_empty() {
                     if !verse.spellcheck(&env.bins) {
-                        eprintln!("dwvsh: {}: command not found", verse.verb());
+                        env.bins = path::refresh();
+                        if !verse.spellcheck(&env.bins) {
+                            eprintln!("dwvsh: {}: command not found", verse.verb());
 
-                        if verse.meter != Rune::And {
-                            continue;
+                            if verse.meter != Rune::And {
+                                continue;
+                            }
                         }
                     }
+                } else {
+                    continue;
                 }
 
                 if stdout {