Add wrapper for global shell environment

Instead of having to pass around a bunch of different data structures
for various shell functions, create the wrapper compose::Environment,
which serves as a global shell state. It is configured via
login/profile/rc scripts initially, but can of course be modified
throughout the lifetime of the shell.

6 files changed, 45 insertions, 22 deletions

diff --git a/src/compose.rs b/src/compose.rs
index 8c4b3ea..3d2a2db 100644
--- a/src/compose.rs
+++ b/src/compose.rs
@@ -1,8 +1,13 @@
 use crate::poem::{read::Readable, recite::Reciteable, Poem};
+pub mod environment;
+pub use environment::Environment;
 use std::fs;
 use std::path::PathBuf;
 
-pub fn env() {
+pub fn env() -> Environment {
+    // Create a new Environment object, to store some extra shell info
+    let mut env = Environment::new();
+
     // Use local repo path if running the debug target
     let global_rc = if cfg!(debug_assertions) {
         let mut base = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
@@ -17,11 +22,14 @@ pub fn env() {
     local_rc.push(".dwvshrc");
 
     // Read, read, and recite
-    rrr(global_rc);
-    rrr(local_rc);
+    rrr(global_rc, &mut env);
+    rrr(local_rc, &mut env);
+
+    // Return the new environment
+    env
 }
 
-fn rrr(path: PathBuf) {
+fn rrr(path: PathBuf, env: &mut Environment) {
     let poetry = match fs::read_to_string(&path) {
         Ok(poetry) => poetry,
         Err(e) => {
@@ -47,8 +55,7 @@ fn rrr(path: PathBuf) {
         }
     };
 
-    let mut bins = vec![];
-    match poem.recite(&mut bins, None) {
+    match poem.recite(env, None) {
         Ok(_) => {}
         Err(e) => {
             eprintln!("dwvsh: {}", e.to_string().to_lowercase());
diff --git a/src/compose/environment.rs b/src/compose/environment.rs
new file mode 100644
index 0000000..219a597
--- /dev/null
+++ b/src/compose/environment.rs
@@ -0,0 +1,13 @@
+pub struct Environment {
+    pub aliases: Vec<String>,
+    pub bins: Vec<String>,
+}
+
+impl Environment {
+    pub fn new() -> Self {
+        Environment {
+            aliases: vec![],
+            bins: vec![],
+        }
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index ce5f611..898d19e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -4,6 +4,7 @@ mod path;
 mod poem;
 use poem::{read::Readable, recite::Reciteable, Poem};
 mod compose;
+use compose::Environment;
 
 /// Starts the main shell loop
 ///
@@ -20,9 +21,9 @@ mod compose;
 ///     repl(prompt, &mut at_prompt);
 /// }
 /// ```
-fn repl(prompt: &str, at_prompt: &mut Arc<Mutex<bool>>) {
+fn repl(prompt: &str, at_prompt: &mut Arc<Mutex<bool>>, env: &mut Environment) {
     // Initial path refresh on startup
-    let mut bins: Vec<String> = path::refresh();
+    env.bins = path::refresh();
 
     // Main shell loop
     loop {
@@ -67,7 +68,7 @@ fn repl(prompt: &str, at_prompt: &mut Arc<Mutex<bool>>) {
         };
 
         // Recite the poem
-        match poem.recite(&mut bins, None) {
+        match poem.recite(env, None) {
             Ok(_) => {}
             Err(e) => eprintln!("dwvsh: {}", e.to_string().to_lowercase()),
         }
@@ -81,7 +82,7 @@ fn main() {
     // Compose the environment for dwvsh
     // TODO: All instances of `env!("HOME")` need to be changed to use env::var
     // TODO: Will probably need to set $HOME in dwv{profile,login} via passwd
-    compose::env();
+    let mut env = compose::env();
 
     // Set the prompt
     let prompt = "|> ";
@@ -102,5 +103,5 @@ fn main() {
     };
 
     // Begin evaluating commands
-    repl(prompt, &mut at_prompt);
+    repl(prompt, &mut at_prompt, &mut env);
 }
diff --git a/src/poem/anthology.rs b/src/poem/anthology.rs
index b9e747c..f1adae7 100644
--- a/src/poem/anthology.rs
+++ b/src/poem/anthology.rs
@@ -19,13 +19,13 @@ pub fn lookup(verb: &str) -> Option<usize> {
     INDEX.iter().position(|v| v.to_string() == verb)
 }
 
-pub fn incant(verse: &Verse, index: usize, bins: &mut Vec<String>) -> i32 {
+pub fn incant(verse: &Verse, index: usize, env: &mut Environment) -> i32 {
     let verb = INDEX[index];
     match verb {
         "cd" => cd::incant(verse),
         "exit" => exit::incant(),
         "export" => export::incant(verse),
-        "source" => source::incant(verse, bins),
+        "source" => source::incant(verse, env),
         _ => unreachable!(),
     }
 }
diff --git a/src/poem/anthology/source.rs b/src/poem/anthology/source.rs
index f7b9a0b..b4148cb 100644
--- a/src/poem/anthology/source.rs
+++ b/src/poem/anthology/source.rs
@@ -1,8 +1,9 @@
+use crate::compose::Environment;
 use crate::poem::Verse;
 use crate::poem::{read::Readable, recite::Reciteable, Poem};
 use std::fs;
 
-pub fn incant(verse: &Verse, bins: &mut Vec<String>) -> i32 {
+pub fn incant(verse: &Verse, env: &mut Environment) -> i32 {
     let files = match verse.clause() {
         Some(clause) => clause,
         None => {
@@ -32,7 +33,7 @@ pub fn incant(verse: &Verse, bins: &mut Vec<String>) -> i32 {
             }
         };
 
-        match poem.recite(bins, None) {
+        match poem.recite(env, None) {
             Ok(_) => {}
             Err(e) => {
                 eprintln!("dwvsh: {}", e.to_string().to_lowercase());
diff --git a/src/poem/recite.rs b/src/poem/recite.rs
index f2af591..e37b7c6 100644
--- a/src/poem/recite.rs
+++ b/src/poem/recite.rs
@@ -1,5 +1,6 @@
 mod ps;
 use super::Poem;
+use crate::compose::Environment;
 use crate::path;
 use crate::poem::anthology;
 use crate::poem::elements::rune::Rune;
@@ -10,11 +11,11 @@ use std::{
 };
 
 pub trait Reciteable {
-    fn recite(&self, bins: &mut Vec<String>, stdout: Option<bool>) -> Result<String, io::Error>;
+    fn recite(&self, env: &mut Environment, stdout: Option<bool>) -> Result<String, io::Error>;
 }
 
 impl Reciteable for Poem {
-    fn recite(&self, bins: &mut Vec<String>, stdout: Option<bool>) -> Result<String, io::Error> {
+    fn recite(&self, env: &mut Environment, stdout: Option<bool>) -> Result<String, io::Error> {
         // Should we print to stdout or always capture it
         let stdout = stdout.unwrap_or(true);
 
@@ -84,7 +85,7 @@ impl Reciteable for Poem {
                             Some(poem) => poem,
                             None => break, // TODO: Return an error
                         };
-                        let out = poem.recite(bins, Some(false))?;
+                        let out = poem.recite(env, Some(false))?;
                         if out.contains("\n") {
                             let mut out = out.split("\n");
                             let next = out.next().unwrap_or("").trim();
@@ -121,16 +122,16 @@ impl Reciteable for Poem {
             // Incant the verse if it's a built-in
             let index = anthology::lookup(&verse.verb());
             let status = if index.is_some() {
-                anthology::incant(&verse, index.unwrap(), bins)
+                anthology::incant(&verse, index.unwrap(), env)
             } else {
                 // Incant the verse, based on its meter
                 // Check if the verb exists
                 // 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(bins) {
-                    *bins = path::refresh();
-                    if !verse.spellcheck(bins) {
+                if !verse.spellcheck(&env.bins) {
+                    env.bins = path::refresh();
+                    if !verse.spellcheck(&env.bins) {
                         eprintln!("dwvsh: {}: command not found", verse.verb());
 
                         if verse.meter != Rune::And {