Trait Shell 

pub trait Shell {
    // Required methods
    fn set_env_var(
        &self,
        f: &mut impl Write,
        env_var: &str,
        value: &str,
    ) -> Result<(), ShellError>;
    fn unset_env_var(
        &self,
        f: &mut impl Write,
        env_var: &str,
    ) -> Result<(), ShellError>;
    fn run_script(
        &self,
        f: &mut impl Write,
        path: &Path,
    ) -> Result<(), ShellError>;
    fn extension(&self) -> &str;
    fn executable(&self) -> &str;
    fn create_run_script_command(&self, path: &Path) -> Command;

    // Provided methods
    fn force_utf8(&self, _f: &mut impl Write) -> Result<(), ShellError> { ... }
    fn source_completions(
        &self,
        _f: &mut impl Write,
        _completions_dir: &Path,
    ) -> Result<(), ShellError> { ... }
    fn can_run_script(&self, path: &Path) -> bool { ... }
    fn run_command<'a>(
        &self,
        f: &mut impl Write,
        command: impl IntoIterator<Item = &'a str> + 'a,
    ) -> Result { ... }
    fn set_path(
        &self,
        f: &mut impl Write,
        paths: &[PathBuf],
        modification_behavior: PathModificationBehavior,
        platform: &Platform,
    ) -> Result<(), ShellError> { ... }
    fn path_separator(&self, platform: &Platform) -> &str { ... }
    fn path_var(&self, platform: &Platform) -> &str { ... }
    fn format_env_var(&self, var_name: &str) -> String { ... }
    fn echo(&self, f: &mut impl Write, text: &str) -> Result { ... }
    fn print_env(&self, f: &mut impl Write) -> Result { ... }
    fn write_script(&self, f: &mut impl Write, script: &str) -> Result<()> { ... }
    fn parse_env<'i>(&self, env: &'i str) -> HashMap<&'i str, &'i str> { ... }
    fn line_ending(&self) -> &str { ... }
    fn completion_script_location(&self) -> Option<&'static Path> { ... }
    fn restore_env_var(
        &self,
        f: &mut impl Write,
        key: &str,
        backup_key: &str,
    ) -> Result<(), ShellError> { ... }
}

A trait for generating shell scripts. The trait is implemented for each shell individually.

Example

use std::path::PathBuf;
use rattler_shell::shell::Bash;
use rattler_shell::shell::Shell;

let mut script = String::new();
let shell = Bash;
shell.set_env_var(&mut script, "FOO", "bar").unwrap();

assert_eq!(script, "export FOO=bar\n");

Required Methods

fn set_env_var( &self, f: &mut impl Write, env_var: &str, value: &str, ) -> Result<(), ShellError>

Set an env var by export-ing it.

fn unset_env_var( &self, f: &mut impl Write, env_var: &str, ) -> Result<(), ShellError>

Unset an env var by unset-ing it.

fn run_script(&self, f: &mut impl Write, path: &Path) -> Result<(), ShellError>

Run a script in the current shell.

fn extension(&self) -> &str

The extension that shell scripts for this interpreter usually use.

fn executable(&self) -> &str

The executable that can be called to start this shell.

fn create_run_script_command(&self, path: &Path) -> Command

Constructs a Command that will execute the specified script by this shell.

Provided Methods

fn force_utf8(&self, _f: &mut impl Write) -> Result<(), ShellError>

Write a command to the script that forces the usage of UTF8-encoding for the shell script.

fn source_completions( &self, _f: &mut impl Write, _completions_dir: &Path, ) -> Result<(), ShellError>

Source completion scripts for the shell from a given prefix path. Note: the completions_dir is the directory where the completions are stored. You can use Self::completion_script_location to get the correct location for a given shell type.

fn can_run_script(&self, path: &Path) -> bool

Test to see if the path can be executed by the shell, based on the extension of the path.

fn run_command<'a>( &self, f: &mut impl Write, command: impl IntoIterator<Item = &'a str> + 'a, ) -> Result

Executes a command in the current shell. Use Self::run_script when you want to run another shell script.

fn set_path( &self, f: &mut impl Write, paths: &[PathBuf], modification_behavior: PathModificationBehavior, platform: &Platform, ) -> Result<(), ShellError>

Set the PATH variable to the given paths.

fn path_separator(&self, platform: &Platform) -> &str

Path separator

fn path_var(&self, platform: &Platform) -> &str

Returns the name of the PATH variable for the given platform. On Windows, path variables are case-insensitive but not all shells treat them case-insensitive.

fn format_env_var(&self, var_name: &str) -> String

Format the environment variable for the shell.

fn echo(&self, f: &mut impl Write, text: &str) -> Result

Emits echoing certain text to stdout.

fn print_env(&self, f: &mut impl Write) -> Result

Emits writing all current environment variables to stdout.

fn write_script(&self, f: &mut impl Write, script: &str) -> Result<()>

Write the script to the writer and do some post-processing for line-endings. Only really relevant for cmd.exe scripts.

fn parse_env<'i>(&self, env: &'i str) -> HashMap<&'i str, &'i str>

Parses environment variables emitted by the Shell::env command.

fn line_ending(&self) -> &str

Get the line ending for this shell. Only CmdExe uses \r\n.

fn completion_script_location(&self) -> Option<&'static Path>

Return the location where completion scripts are found in a Conda environment.

• bash: share/bash-completion/completions
• zsh: share/zsh/site-functions
• fish: share/fish/vendor_completions.d

The return value must be joined with prefix.join(completion_script_location()).

fn restore_env_var( &self, f: &mut impl Write, key: &str, backup_key: &str, ) -> Result<(), ShellError>

Restores an environment variable from its backup if it exists, otherwise unsets it.

Arguments

• key - The name of the environment variable to restore
• backup_key - The name of the backup environment variable

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl Shell for ShellEnum

impl Shell for Bash

impl Shell for CmdExe

impl Shell for Fish

impl Shell for NuShell

impl Shell for PowerShell

impl Shell for Xonsh

impl Shell for Zsh