chore(error): remove basically all .unwrap() calls except for those…

… in the `plugins` module

src/errors.rs

@@ -116,13 +116,15 @@ pub enum StateError {
     NoNextDirectory,
     FailedToOpenConfigFile(PathBuf),
     FailedToReadConfigFile(PathBuf),
+    UnsupportedTerminal,
 }
 
 /// Error type for errors which occur during path operations.
 pub enum PathError {
     FailedToConvertStringToPath(String),
     FailedToConvertPathToString(PathBuf),
     FailedToCanonicalize(PathBuf),
+    FailedToGetParent(PathBuf),
     UnknownDirectory(PathBuf),
 }
 
@@ -255,6 +257,7 @@ impl Display for StateError {
                     path.display()
                 )
             }
+            UnsupportedTerminal => write!(f, "Terminal is not supported"),
         }
     }
 }
@@ -273,6 +276,13 @@ impl Display for PathError {
             FailedToCanonicalize(path) => {
                 write!(f, "Path '{}' could not be canonicalized", path.display())
             }
+            FailedToGetParent(path) => {
+                write!(
+                    f,
+                    "Parent directory of path '{}' could not be determined",
+                    path.display()
+                )
+            }
             UnknownDirectory(path) => {
                 write!(
                     f,

src/eval.rs

@@ -1,5 +1,4 @@
 pub mod dispatcher;
-mod parser;
 pub mod readline;
 mod symbols;
 mod tokenizer;

src/eval/readline.rs

@@ -8,6 +8,7 @@ use rustyline::{
     Completer, CompletionType, Config, Editor, Helper, Highlighter, Hinter, Validator,
 };
 
+use crate::errors::{Handle, Result};
 use crate::state::shell::ShellState;
 
 #[derive(Helper, Completer, Hinter, Validator, Highlighter)]
@@ -39,15 +40,16 @@ pub struct LineEditor {
 
 impl LineEditor {
     // Creates a LineEditor with the default configuration and history file
-    pub fn new(history_file: &str) -> Self {
+    pub fn new(history_file: &str) -> Result<Self> {
         let config = Config::builder()
             .history_ignore_space(true)
             .completion_type(CompletionType::Fuzzy)
             .build();
 
         let helper = LineEditorHelper::new();
 
-        let mut editor = Editor::with_config(config).unwrap();
+        let mut editor =
+            Editor::with_config(config).replace_err(state_err!(UnsupportedTerminal))?;
         editor.set_helper(Some(helper));
         if editor.load_history(history_file).is_err() {
             println!("No existing history file found, attempting to create one...");
@@ -61,7 +63,7 @@ impl LineEditor {
             }
         }
 
-        Self { editor }
+        Ok(Self { editor })
     }
 
     pub fn prompt_and_read_line(&mut self, shell: &ShellState) -> Option<String> {

src/exec/builtins.rs

@@ -16,7 +16,6 @@ use crossterm::cursor::MoveTo;
 use crossterm::execute;
 use crossterm::style::Stylize;
 use crossterm::terminal::{self, Clear, ClearType};
-use fs_err;
 
 use super::builtin_arguments::ListDirectoryArguments;
 use super::commands::{Executable, Runnable};

src/main.rs

@@ -5,7 +5,7 @@ mod exec;
 mod plugins;
 mod state;
 
-use errors::Result;
+use errors::{Result, RushError};
 use eval::{Dispatcher, LineEditor};
 use plugins::host::PluginHost;
 use state::ShellState;
@@ -18,9 +18,14 @@ fn main() {
     };
 
     let plugins = PluginHost::new(shell.clone());
+
     // The LineEditor type is responsible for reading lines of input from the user, storing history,
     // providing tab completion and other line-editing features
-    let mut line_editor = LineEditor::new("./config/history.rush");
+    let mut line_editor = match LineEditor::new("./config/history.rush") {
+        Ok(editor) => editor,
+        Err(err) => crash_with_error(err),
+    };
+
     // The Dispatcher type is responsible for resolving command names to actual function calls,
     // or executables if needed, and then invoking them with the given arguments
     let dispatcher = Dispatcher::default();
@@ -41,3 +46,10 @@ fn handle_error(potential_error: Result<()>, shell: &mut ShellState) {
         eprintln!("{}", error);
     }
 }
+
+// Handles errors from which the shell cannot recover, mainly errors arising from shell setup
+fn crash_with_error(error: RushError) -> ! {
+    eprintln!("{}", error);
+    // TODO: Maybe return status code for each error type?
+    std::process::exit(1);
+}

src/state/config.rs

@@ -37,7 +37,9 @@ impl Configuration {
     // Scans a configuration file for settings and updates the configuration accordingly
     pub fn from_file(filename: &str) -> Result<Self> {
         let filename = PathBuf::from(filename);
-        let dirname = filename.parent().unwrap();
+        let dirname = filename
+            .parent()
+            .replace_err(path_err!(FailedToGetParent(filename)))?;
 
         let mut config = Self::default();
         let file = File::open(filename.clone())