Use Shells instead of Box<dyn Shell> everywhere

src/commands/completions.rs

@@ -1,9 +1,9 @@
 use super::command::Command;
 use crate::config::FnmConfig;
-use crate::shell::{infer_shell, Shell};
+use crate::shell::infer_shell;
 use crate::{cli::Cli, shell::Shells};
 use clap::{CommandFactory, Parser, ValueEnum};
-use clap_complete::{Generator, Shell as ClapShell};
+use clap_complete::{Generator, Shell};
 use thiserror::Error;
 
 #[derive(Parser, Debug)]
@@ -18,12 +18,11 @@ impl Command for Completions {
 
     fn apply(self, _config: &FnmConfig) -> Result<(), Self::Error> {
         let mut stdio = std::io::stdout();
-        let shell: Box<dyn Shell> = self
+        let shell: Shell = self
             .shell
-            .map(Into::into)
-            .or_else(|| infer_shell().map(Into::into))
-            .ok_or(Error::CantInferShell)?;
-        let shell: ClapShell = shell.into();
+            .or_else(infer_shell)
+            .ok_or(Error::CantInferShell)?
+            .into();
         let app = Cli::command();
         shell.generate(&app, &mut stdio);
         Ok(())

src/commands/env.rs

@@ -102,9 +102,8 @@ impl Command for Env {
             return Ok(());
         }
 
-        let shell: Box<dyn Shell> = self
+        let shell = self
             .shell
-            .map(Into::into)
             .or_else(infer_shell)
             .ok_or(Error::CantInferShell)?;
 

src/shell/infer/mod.rs

@@ -7,14 +7,16 @@ pub use self::unix::infer_shell;
 #[cfg(not(unix))]
 pub use self::windows::infer_shell;
 
-pub(self) fn shell_from_string(shell: &str) -> Option<Box<dyn super::Shell>> {
-    use super::{Bash, Fish, PowerShell, WindowsCmd, Zsh};
+use super::Shells;
+
+pub(self) fn shell_from_string(shell: &str) -> Option<Shells> {
     match shell {
-        "sh" | "bash" => return Some(Box::from(Bash)),
-        "zsh" => return Some(Box::from(Zsh)),
-        "fish" => return Some(Box::from(Fish)),
-        "pwsh" | "powershell" => return Some(Box::from(PowerShell)),
-        "cmd" => return Some(Box::from(WindowsCmd)),
+        "sh" | "bash" => return Some(Shells::Bash),
+        "zsh" => return Some(Shells::Zsh),
+        "fish" => return Some(Shells::Fish),
+        "pwsh" | "powershell" => return Some(Shells::PowerShell),
+        #[cfg(windows)]
+        "cmd" => return Some(Shells::Cmd),
         cmd_name => log::debug!("binary is not a supported shell: {:?}", cmd_name),
     };
     None

src/shell/infer/unix.rs

@@ -1,6 +1,6 @@
 #![cfg(unix)]
 
-use crate::shell::Shell;
+use crate::shell::Shells;
 use log::debug;
 use std::io::{Error, ErrorKind};
 use thiserror::Error;
@@ -13,7 +13,7 @@ struct ProcessInfo {
 
 const MAX_ITERATIONS: u8 = 10;
 
-pub fn infer_shell() -> Option<Box<dyn Shell>> {
+pub fn infer_shell() -> Option<Shells> {
     let mut pid = Some(std::process::id());
     let mut visited = 0;
 

src/shell/infer/windows.rs

@@ -4,7 +4,7 @@ use crate::shell::Shell;
 use std::ffi::OsStr;
 use sysinfo::{ProcessExt, System, SystemExt};
 
-pub fn infer_shell() -> Option<Box<dyn Shell>> {
+pub fn infer_shell() -> Option<Shells> {
     let mut system = System::new();
     let mut current_pid = sysinfo::get_current_pid().ok();
 

src/shell/shell.rs

@@ -36,9 +36,9 @@ impl Display for Shells {
     }
 }
 
-impl From<Shells> for Box<dyn Shell> {
-    fn from(shell: Shells) -> Box<dyn Shell> {
-        match shell {
+impl Shells {
+    fn actual_shell(&self) -> Box<dyn Shell> {
+        match self {
             Shells::Zsh => Box::from(super::zsh::Zsh),
             Shells::Bash => Box::from(super::bash::Bash),
             Shells::Fish => Box::from(super::fish::Fish),
@@ -49,8 +49,26 @@ impl From<Shells> for Box<dyn Shell> {
     }
 }
 
-impl From<Box<dyn Shell>> for clap_complete::Shell {
-    fn from(shell: Box<dyn Shell>) -> Self {
+impl Shell for Shells {
+    fn path(&self, path: &Path) -> anyhow::Result<String> {
+        self.actual_shell().path(path)
+    }
+
+    fn set_env_var(&self, name: &str, value: &str) -> String {
+        self.actual_shell().set_env_var(name, value)
+    }
+
+    fn use_on_cd(&self, config: &crate::config::FnmConfig) -> anyhow::Result<String> {
+        self.actual_shell().use_on_cd(config)
+    }
+
+    fn to_clap_shell(&self) -> clap_complete::Shell {
+        self.actual_shell().to_clap_shell()
+    }
+}
+
+impl From<Shells> for clap_complete::Shell {
+    fn from(shell: Shells) -> Self {
         shell.to_clap_shell()
     }
 }