Fix regression with aliases

Fixed a regression that was introduced in:
1415c8f9b89699000ef8d864ff8f0e1bebca4a5f.

Moving aliases to read() broke how pipes worked. This commit removes the
troublesome append!() macro, and replaces it with some logic in the
add() function (impl Appendable for Poem).

2 files changed, 65 insertions, 42 deletions

diff --git a/src/poem/read.rs b/src/poem/read.rs
index 3578a92..875bf76 100644
--- a/src/poem/read.rs
+++ b/src/poem/read.rs
@@ -5,7 +5,7 @@ use super::{
 use core::fmt;
 mod parse;
 use crate::compose::Environment;
-use crate::{append, next, poem, remark, string};
+use crate::{next, poem, remark, string};
 
 #[derive(Debug, PartialEq, Eq)]
 pub enum Mishap {
@@ -41,7 +41,13 @@ impl fmt::Display for Mishap {
 /// A [Poem] can add more [Verse]s to itself
 trait Appendable {
     type Type;
-    fn add(&mut self, verse: &mut Self::Type, meter: Rune, last: Rune);
+    fn add(
+        &mut self,
+        verse: &mut Self::Type,
+        meter: Rune,
+        last: Rune,
+        env: &Environment,
+    ) -> Result<(), Mishap>;
 }
 
 impl Appendable for Poem {
@@ -51,20 +57,65 @@ impl Appendable for Poem {
     ///
     /// Push a [Verse] to the [Poem] after checking that the [Verse] is not
     /// empty. Also sets the meter of the [Verse].
-    fn add(&mut self, verse: &mut Self::Type, last: Rune, meter: Rune) {
+    fn add(
+        &mut self,
+        verse: &mut Self::Type,
+        last: Rune,
+        meter: Rune,
+        env: &Environment,
+    ) -> Result<(), Mishap> {
         if verse.is_empty() {
-            return;
+            return Ok(());
         }
 
-        // Check the meter
-        verse.meter = meter;
-        if last == Rune::Couplet || meter == Rune::Couplet {
-            verse.couplet = true;
+        // Check for aliases
+        match env.aliases.get(&verse.verb()) {
+            Some(alias) => {
+                // Interpret the alias (could be a complex poem)
+                let mut poem = Poem::read(alias.to_string(), env)?;
+
+                // Try and get the last verse
+                let lv = match poem.last_mut() {
+                    Some(lv) => lv,
+                    None => unreachable!(), // Should be caught by a Mishap above
+                };
+
+                // If the verse has a clause, add it to the last verse in
+                // the poem from the alias
+                if verse.clause().is_some() {
+                    for word in verse.clause().unwrap().iter() {
+                        lv.stanza.push(word.to_string());
+                    }
+                }
+
+                // Check the meter
+                lv.meter = meter;
+                if last == Rune::Couplet || meter == Rune::Couplet {
+                    verse.couplet = true;
+                }
+
+                // Push verse(s)
+                for v in poem.iter() {
+                    self.push(v.clone());
+                }
+            }
+            None => {
+                // Check the meter
+                verse.meter = meter;
+                if last == Rune::Couplet || meter == Rune::Couplet {
+                    verse.couplet = true;
+                }
+
+                // Push verse(s)
+                self.push(verse.clone());
+            }
         }
 
-        // Push verse(s) and clear the current verse stack
-        self.push(verse.clone());
+        // Clear the current verse stack
         verse.clear();
+
+        // Unit
+        Ok(())
     }
 }
 
@@ -127,8 +178,8 @@ impl Readable for Poem {
                     }
 
                     // Push the verse and break
-                    // poem.add(&mut verse, last, Rune::None);
-                    append!(poem, last, Rune::None, verse, env);
+                    poem.add(&mut verse, last, Rune::None, env)?;
+                    // append!(poem, last, Rune::None, verse, env);
                     break;
                 }
             };
@@ -232,8 +283,8 @@ impl Readable for Poem {
                 // These meters indicate the end of a verse
                 Rune::Couplet | Rune::Quiet | Rune::And | Rune::Continue => {
                     verse.add(&mut word);
-                    // poem.add(&mut verse, last, rune);
-                    append!(poem, last, rune, verse, env);
+                    poem.add(&mut verse, last, rune, env)?;
+                    // append!(poem, last, rune, verse, env);
                 }
 
                 // Interpret ~ as $HOME
diff --git a/src/poem/read/parse.rs b/src/poem/read/parse.rs
index 58c8fde..7b01d85 100644
--- a/src/poem/read/parse.rs
+++ b/src/poem/read/parse.rs
@@ -84,31 +84,3 @@ macro_rules! poem {
         $word.push('\x0b');
     };
 }
-
-/// Append a verse to the poem
-///
-/// Append a verse to poem, first checking for aliases in the environment, and
-/// processing the alias first, if necessary.
-#[macro_export]
-macro_rules! append {
-    ($poem:expr, $last:expr, $meter:expr, $verse:expr, $env:expr) => {
-        if !$verse.is_empty() {
-            match $env.aliases.get(&$verse.verb()) {
-                Some(alias) => {
-                    let alias = alias.to_string();
-                    let mut poem = Poem::read(alias, $env)?;
-                    let len = poem.len();
-                    for (i, verse) in poem.iter_mut().enumerate() {
-                        if $verse.clause().is_some() && i + 1 == len {
-                            verse.stanza.append(&mut $verse.clause().unwrap());
-                        }
-                        $poem.push(verse.clone());
-                    }
-                }
-                None => {
-                    $poem.add(&mut $verse, $last, $meter);
-                }
-            }
-        }
-    };
-}