activate.rs

use std::path::{Path, PathBuf};

use crate::config::Settings;
use crate::env::PATH_KEY;
use crate::file;
use crate::file::{canonicalize_or_self, touch_dir};
use crate::shell::{
    ActivateOptions, ActivatePrelude, EXAMPLE_SHELL, Shell, ShellType, require_shell,
};
use crate::toolset::env_cache::CachedEnv;
use crate::{dirs, env};
use eyre::Result;

/// Print the script to activate mise in an interactive shell
///
/// Evaluate this command's output with the syntax for your shell; running it alone
/// only prints the script. Activation updates tools and environment variables as
/// this shell changes directories.
///
/// Add the matching example below once to your interactive startup file:
/// ~/.bashrc for Bash, ~/.zshrc for Zsh, ~/.config/fish/config.fish for Fish,
/// or $PROFILE for PowerShell. For Nushell, Elvish and other shells, see
/// https://mise.jdx.dev/shell-setup.html.
///
/// The mise executable must be on PATH before that line runs. Otherwise use its
/// absolute path, for example `eval "$(~/.local/bin/mise activate zsh)"`.
///
/// Use `mise exec -- command` for scripts and CI that do not need interactive hooks.
/// The `status.*` settings control the messages mise prints when you change
/// directories.
#[derive(Debug, usage_rs::Args)]
#[usage(
    verbatim_doc_comment,
    example(r#"eval "$(mise activate bash)""#, help = "Activate mise in Bash"),
    example(r#"eval "$(mise activate zsh)""#, help = "Activate mise in Zsh"),
    example("mise activate fish | source", help = "Activate mise in Fish"),
    example("execx($(mise activate xonsh))", help = "Activate mise in Xonsh"),
    example(
        "(&mise activate pwsh) | Out-String | Invoke-Expression",
        help = "Activate mise in PowerShell"
    )
)]
pub(crate) struct Activate {
    /// Shell type to generate the script for
    ///
    /// Defaults to the shell named by MISE_SHELL or SHELL. mise reports an error when
    /// neither names a supported shell, as in PowerShell and cmd on Windows.
    #[usage(value_enum)]
    shell_type: Option<ShellType>,

    /// Suppress non-error messages from the hook that runs at each prompt
    #[usage(long, short)]
    quiet: bool,

    /// Shell type to generate the script for
    #[usage(long, short, hide = true, value_enum)]
    shell: Option<ShellType>,

    /// Do not run hook-env automatically
    ///
    /// Use it for debugging: after `eval "$(mise activate zsh --no-hook-env)"`, run
    /// `mise hook-env` yourself to print the shell code it would evaluate, or
    /// `mise hook-env --trace` for more detail.
    #[usage(long)]
    no_hook_env: bool,

    /// Put the shims directory on PATH instead of updating PATH at each prompt
    ///
    /// Roughly equivalent to:
    ///
    ///     PATH="$HOME/.local/share/mise/shims:$PATH"
    ///
    /// Shims do not support every feature of `mise activate`; see
    /// https://mise.jdx.dev/dev-tools/shims.html#shims-vs-path.
    #[usage(long, verbatim_doc_comment)]
    shims: bool,

    /// Show "mise: <TOOL>@<VERSION>" message when changing directories
    #[usage(long, hide = true)]
    status: bool,
}

impl Activate {
    pub(crate) fn run(self) -> Result<()> {
        let shell = require_shell(
            self.shell_type.or(self.shell),
            &format!("Name the shell: `mise activate {EXAMPLE_SHELL}`."),
        )?;

        // touch ROOT to allow hook-env to run
        let _ = touch_dir(&dirs::DATA);

        let mise_bin = if cfg!(target_os = "linux") {
            // linux dereferences symlinks, so use argv0 instead
            let argv0 = PathBuf::from(&*env::ARGV0);
            let path = if argv0.is_absolute() {
                argv0
            } else {
                which::which(&*env::ARGV0).unwrap_or_else(|_| env::MISE_BIN.clone())
            };
            if path.is_absolute() {
                path
            } else {
                std::env::current_dir()
                    .map(|cwd| cwd.join(path))
                    .unwrap_or_else(|_| env::MISE_BIN.clone())
            }
        } else {
            env::MISE_BIN.clone()
        };
        match self.shims {
            true => self.activate_shims(shell.as_ref(), &mise_bin)?,
            false => self.activate(shell.as_ref(), &mise_bin)?,
        }

        Ok(())
    }

    fn activate_shims(&self, shell: &dyn Shell, mise_bin: &Path) -> std::io::Result<()> {
        let exe_dir = mise_bin.parent().unwrap();
        let user_shims = dirs::shims();
        let system_shims = dirs::system_shims();
        let mut shim_dirs = vec![user_shims];
        if system_shims.is_dir() && !file::storage_paths_eq(&shim_dirs[0], &system_shims) {
            shim_dirs.push(system_shims);
        }
        let mut prelude = vec![];
        // The shims dir is always (move-)prepended so it stays at the front of PATH
        // even when activation is re-sourced (e.g. VS Code terminals) — see #8757.
        // The mise executable's own dir only needs to be present so `mise` is
        // callable, so it uses the guarded prepend: this avoids re-prepending (and
        // thereby reordering) a system dir such as /usr/bin that is already in PATH
        // for deb/rpm installs, which would otherwise move it ahead of
        // /usr/local/bin (#10264).
        let prepended_exe_dir = if let Some(p) = self.prepend_path(exe_dir) {
            prelude.push(p);
            true
        } else {
            false
        };
        let has_command_wrappers = dirs::COMMAND_WRAPPERS.is_dir();
        let mut dispatch_dirs = shim_dirs.iter().map(PathBuf::as_path).collect::<Vec<_>>();
        if has_command_wrappers {
            dispatch_dirs.insert(0, dirs::COMMAND_WRAPPERS.as_path());
        }
        let dispatch_dirs_already_first = are_dirs_first_in_paths(&env::PATH, &dispatch_dirs);
        if shell.supports_move_path() || prepended_exe_dir || !dispatch_dirs_already_first {
            // Prepend in reverse order so user shims retain precedence over system
            // shims in shells where each operation inserts at the front.
            let mut path_changed = prepended_exe_dir;
            for shims_dir in shim_dirs.iter().rev() {
                if let Some(p) = self.shims_prepend_path(shell, shims_dir, path_changed) {
                    prelude.push(p);
                    path_changed = true;
                }
            }
            if has_command_wrappers
                && let Some(p) = self.shims_prepend_path(shell, &dirs::COMMAND_WRAPPERS, true)
            {
                prelude.push(p);
            }
        }
        miseprint!("{}", shell.format_activate_prelude(&prelude))?;
        Ok(())
    }

    fn activate(&self, shell: &dyn Shell, mise_bin: &Path) -> std::io::Result<()> {
        let mut prelude = vec![];
        // Preserve the user's PATH before adding the shim boundary. Shell activation
        // normally snapshots this after preludes run, which would otherwise make
        // `mise deactivate` restore mise's own shim farms.
        if env::__MISE_ORIG_PATH.is_none() {
            let path = std::env::join_paths(&*env::PATH)
                .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidInput, err))?;
            prelude.push(ActivatePrelude::Set(
                "__MISE_ORIG_PATH".to_string(),
                path.to_string_lossy().to_string(),
            ));
        }
        let shim_path_update =
            if Settings::get().activate_shims && Settings::get().not_found_auto_install {
                position_shims_before_path()?
            } else {
                remove_shims_from_path()?
            };
        if let Some(set_path) = shim_path_update {
            prelude.push(set_path);
        }
        let exe_dir = mise_bin.parent().unwrap();
        let mut flags = vec![];
        if self.quiet {
            flags.push(" --quiet".to_string());
        }
        if self.status {
            flags.push(" --status".to_string());
        }
        flags.extend(forwarded_logging_flags(&env::ARGS.read().unwrap()));
        if let Some(prepend_path) = self.prepend_path(exe_dir) {
            prelude.push(prepend_path);
        }

        // Generate encryption key for env cache if caching is enabled
        // This key is session-scoped and lost when the shell closes
        if Settings::get().env_cache {
            let key = CachedEnv::ensure_encryption_key();
            prelude.push(ActivatePrelude::Set(
                "__MISE_ENV_CACHE_KEY".to_string(),
                key,
            ));
        }

        miseprint!(
            "{}",
            shell.activate(ActivateOptions {
                exe: mise_bin.to_path_buf(),
                flags: flags.join(""),
                no_hook_env: self.no_hook_env,
                prelude,
            })
        )?;
        Ok(())
    }

    fn prepend_path(&self, p: &Path) -> Option<ActivatePrelude> {
        if is_dir_not_in_nix(p) && !is_dir_in_path(p) && !p.is_relative() {
            Some(ActivatePrelude::Prepend(
                PATH_KEY.to_string(),
                p.to_string_lossy().to_string(),
            ))
        } else {
            None
        }
    }

    /// Used by activate_shims for the shims directory. Shells with native path
    /// deduplication move the existing entry to the front. Other shells prepend
    /// only when the shims are not already first, which preserves precedence
    /// without growing PATH on every re-source. If an earlier prelude changes
    /// PATH, prepend again so the shims remain first after that change.
    fn shims_prepend_path(
        &self,
        shell: &dyn Shell,
        p: &Path,
        path_changed_before: bool,
    ) -> Option<ActivatePrelude> {
        if !is_dir_not_in_nix(p) || p.is_relative() {
            return None;
        }
        if shell.supports_move_path() {
            Some(ActivatePrelude::MovePrepend(
                PATH_KEY.to_string(),
                p.to_string_lossy().to_string(),
            ))
        } else if should_prepend_shims(&env::PATH, p, path_changed_before) {
            Some(ActivatePrelude::Prepend(
                PATH_KEY.to_string(),
                p.to_string_lossy().to_string(),
            ))
        } else {
            None
        }
    }
}

/// Logging flags given to `mise activate` that have to keep applying to every later
/// `hook-env`, since that — not `activate` — is what prints the per-directory output.
///
/// Only `--quiet` reaches [`Activate`] as a field; `--silent` and `--log-level` are global
/// flags on [`crate::cli::Cli`], so they are read back from the argv `Cli::run` recorded.
/// `--quiet` is left to `Activate::quiet` to avoid emitting it twice, and the verbosity
/// flags (`-v`, `--debug`, `--trace`) are deliberately not forwarded — the same split
/// `hook_env::has_preclap_logging_flag` draws between flags that suppress warnings and
/// flags that do not.
///
/// Flags are forwarded in the order they were given, so `hook-env`'s own
/// `overrides_with_all` resolves them exactly as this invocation did.
/// `--log-level <LEVEL>` is normalized to `--log-level=<LEVEL>` so the flag survives as a
/// single word when the shell templates split the flag string.
fn forwarded_logging_flags(args: &[String]) -> Vec<String> {
    let mut flags = vec![];
    let mut remaining = args.iter();
    while let Some(arg) = remaining.next() {
        if arg == "--silent" {
            flags.push(" --silent".to_string());
        } else if let Some(level) = arg.strip_prefix("--log-level=") {
            flags.push(format!(" --log-level={level}"));
        } else if arg == "--log-level"
            && let Some(level) = remaining.next()
        {
            flags.push(format!(" --log-level={level}"));
        }
    }
    flags
}

fn position_shims_before_path() -> std::io::Result<Option<ActivatePrelude>> {
    let user_shims = dirs::shims();
    let system_shims = dirs::system_shims();
    let mut path = vec![user_shims];
    if system_shims.is_dir() && !file::storage_paths_eq(&path[0], &system_shims) {
        path.push(system_shims);
    }
    path.extend(
        env::PATH
            .iter()
            .filter(|path| !file::is_mise_shims_dir(path))
            .cloned(),
    );
    let path = std::env::join_paths(path)
        .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidInput, err))?;
    Ok(Some(ActivatePrelude::Set(
        PATH_KEY.to_string(),
        path.to_string_lossy().to_string(),
    )))
}

fn remove_shims_from_path() -> std::io::Result<Option<ActivatePrelude>> {
    if !env::PATH.iter().any(|path| file::is_mise_shims_dir(path)) {
        return Ok(None);
    }
    let path = std::env::join_paths(
        env::PATH
            .iter()
            .filter(|path| !file::is_mise_shims_dir(path)),
    )
    .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidInput, err))?;
    Ok(Some(ActivatePrelude::Set(
        PATH_KEY.to_string(),
        path.to_string_lossy().to_string(),
    )))
}

fn is_dir_in_path(dir: &Path) -> bool {
    let dir = canonicalize_or_self(dir);
    env::PATH
        .clone()
        .into_iter()
        .any(|p| canonicalize_or_self(&p) == dir)
}

fn should_prepend_shims(paths: &[PathBuf], dir: &Path, path_changed_before: bool) -> bool {
    path_changed_before || !is_dir_first_in_paths(paths, dir)
}

fn is_dir_first_in_paths(paths: &[PathBuf], dir: &Path) -> bool {
    let dir = canonicalize_or_self(dir);
    paths
        .first()
        .is_some_and(|p| canonicalize_or_self(p) == dir)
}

fn are_dirs_first_in_paths(paths: &[PathBuf], dirs: &[&Path]) -> bool {
    paths.len() >= dirs.len()
        && paths
            .iter()
            .zip(dirs)
            .all(|(path, dir)| canonicalize_or_self(path) == canonicalize_or_self(dir))
}

fn is_dir_not_in_nix(dir: &Path) -> bool {
    !canonicalize_or_self(dir).starts_with("/nix/")
}

#[cfg(test)]
mod tests {
    use super::{
        are_dirs_first_in_paths, forwarded_logging_flags, is_dir_first_in_paths,
        should_prepend_shims,
    };
    use std::path::PathBuf;

    fn args(values: &[&str]) -> Vec<String> {
        values.iter().map(|value| value.to_string()).collect()
    }

    #[test]
    fn forwards_silent_so_it_reaches_hook_env() {
        assert_eq!(
            forwarded_logging_flags(&args(&["mise", "activate", "bash", "--silent"])),
            vec![" --silent".to_string()]
        );
    }

    #[test]
    fn forwards_a_flag_given_before_the_subcommand_too() {
        assert_eq!(
            forwarded_logging_flags(&args(&["mise", "--silent", "activate", "bash"])),
            vec![" --silent".to_string()]
        );
    }

    #[test]
    fn normalizes_both_log_level_spellings_to_one_word() {
        let separate =
            forwarded_logging_flags(&args(&["mise", "activate", "bash", "--log-level", "error"]));
        let joined =
            forwarded_logging_flags(&args(&["mise", "activate", "bash", "--log-level=error"]));
        assert_eq!(separate, vec![" --log-level=error".to_string()]);
        assert_eq!(separate, joined);
    }

    #[test]
    fn keeps_the_order_so_hook_env_resolves_overrides_the_same_way() {
        assert_eq!(
            forwarded_logging_flags(&args(&[
                "mise",
                "activate",
                "bash",
                "--silent",
                "--log-level=error"
            ])),
            vec![" --silent".to_string(), " --log-level=error".to_string()]
        );
    }

    #[test]
    fn leaves_quiet_to_the_activate_flag_and_skips_verbosity() {
        // `--quiet` is carried by `Activate::quiet`; forwarding it here would duplicate it.
        // `-v`/`--debug`/`--trace` raise the level rather than suppressing warnings.
        for arg in ["-q", "--quiet", "-v", "--debug", "--trace"] {
            assert!(
                forwarded_logging_flags(&args(&["mise", "activate", "bash", arg])).is_empty(),
                "{arg} should not be forwarded"
            );
        }
    }

    #[test]
    fn a_trailing_log_level_without_a_value_is_dropped() {
        assert!(
            forwarded_logging_flags(&args(&["mise", "activate", "bash", "--log-level"])).is_empty()
        );
    }

    #[test]
    fn nothing_is_forwarded_without_a_logging_flag() {
        assert!(forwarded_logging_flags(&args(&["mise", "activate", "bash"])).is_empty());
    }

    #[test]
    fn detects_only_a_matching_first_path_entry() {
        let dir = tempfile::tempdir().unwrap();
        let target = dir.path().to_path_buf();
        let equivalent = target.join(".");
        let other = PathBuf::from("/other");

        assert!(!is_dir_first_in_paths(&[], &target));
        assert!(is_dir_first_in_paths(&[equivalent, other.clone()], &target));
        assert!(!is_dir_first_in_paths(&[other, target.clone()], &target));

        assert!(!should_prepend_shims(
            std::slice::from_ref(&target),
            &target,
            false
        ));
        assert!(should_prepend_shims(
            std::slice::from_ref(&target),
            &target,
            true
        ));
    }

    #[test]
    fn detects_an_existing_dispatch_prefix() {
        let root = tempfile::tempdir().unwrap();
        let wrappers = root.path().join("wrappers");
        let shims = root.path().join("shims");
        let other = root.path().join("other");

        assert!(are_dirs_first_in_paths(
            &[wrappers.clone(), shims.clone(), other.clone()],
            &[&wrappers, &shims]
        ));
        assert!(!are_dirs_first_in_paths(
            &[shims.clone(), wrappers.clone(), other],
            &[&wrappers, &shims]
        ));
        assert!(!are_dirs_first_in_paths(
            std::slice::from_ref(&wrappers),
            &[&wrappers, &shims]
        ));
    }
}