added "en" command

Fixes #1655

docs/.vitepress/cli_commands.ts

@@ -96,6 +96,9 @@ export const commands: { [key: string]: Command } = {
   doctor: {
     hide: false,
   },
+  en: {
+    hide: false,
+  },
   env: {
     hide: false,
   },

docs/cli/en.md

@@ -0,0 +1,38 @@
+# `mise en`
+
+- **Usage**: `mise en [-s --shell <SHELL>] [DIR]`
+- **Source code**: [`src/cli/en.rs`](https://github.com/jdx/mise/blob/main/src/cli/en.rs)
+
+[experimental] starts a new shell with the mise environment built from the current configuration
+
+This is an alternative to `mise activate` that allows you to explicitly start a mise session.
+It will have the tools and environment variables in the configs loaded.
+Note that changing directories will not update the mise environment.
+
+## Arguments
+
+### `[DIR]`
+
+Directory to start the shell in
+
+**Default:** `.`
+
+## Flags
+
+### `-s --shell <SHELL>`
+
+Shell to start
+
+Defaults to $SHELL
+
+Examples:
+
+    $ mise en .
+    $ node -v
+    v20.0.0
+
+    Skip loading bashrc:
+    $ mise en -s "bash --norc"
+
+    Skip loading zshrc:
+    $ mise en -s "zsh -f"

docs/cli/index.md

@@ -66,6 +66,7 @@ Answer yes to all confirmation prompts
 - [`mise direnv <SUBCOMMAND>`](/cli/direnv.md)
 - [`mise direnv activate`](/cli/direnv/activate.md)
 - [`mise doctor`](/cli/doctor.md)
+- [`mise en [-s --shell <SHELL>] [DIR]`](/cli/en.md)
 - [`mise env [FLAGS] [TOOL@VERSION]...`](/cli/env.md)
 - [`mise exec [FLAGS] [TOOL@VERSION]... [COMMAND]...`](/cli/exec.md)
 - [`mise generate <SUBCOMMAND>`](/cli/generate.md)

man/man1/mise.1

@@ -83,6 +83,9 @@ Output direnv function to use mise inside direnv
 mise\-doctor(1)
 Check mise installation for possible problems
 .TP
+mise\-en(1)
+[experimental] starts a new shell with the mise environment built from the current configuration
+.TP
 mise\-env(1)
 Exports env vars to activate mise a single time
 .TP

mise.usage.kdl

@@ -343,6 +343,30 @@ cmd "doctor" help="Check mise installation for possible problems" {
     [WARN] plugin node is not installed
 "
 }
+cmd "en" help="[experimental] starts a new shell with the mise environment built from the current configuration" {
+    long_help r"[experimental] starts a new shell with the mise environment built from the current configuration
+
+This is an alternative to `mise activate` that allows you to explicitly start a mise session.
+It will have the tools and environment variables in the configs loaded.
+Note that changing directories will not update the mise environment."
+    after_long_help r#"Examples:
+
+    $ mise en .
+    $ node -v
+    v20.0.0
+
+    Skip loading bashrc:
+    $ mise en -s "bash --norc"
+
+    Skip loading zshrc:
+    $ mise en -s "zsh -f"
+"#
+    flag "-s --shell" help="Shell to start" {
+        long_help "Shell to start\n\nDefaults to $SHELL"
+        arg "<SHELL>"
+    }
+    arg "[DIR]" help="Directory to start the shell in" default="."
+}
 cmd "env" help="Exports env vars to activate mise a single time" {
     alias "e"
     long_help r"Exports env vars to activate mise a single time

src/cli/en.rs

@@ -0,0 +1,60 @@
+use crate::cli::exec::Exec;
+use crate::config::Settings;
+use std::ffi::OsString;
+use std::path::PathBuf;
+
+use crate::env;
+
+/// [experimental] starts a new shell with the mise environment built from the current configuration
+///
+/// This is an alternative to `mise activate` that allows you to explicitly start a mise session.
+/// It will have the tools and environment variables in the configs loaded.
+/// Note that changing directories will not update the mise environment.
+#[derive(Debug, clap::Args)]
+#[clap(verbatim_doc_comment, after_long_help = AFTER_LONG_HELP)]
+pub struct En {
+    /// Directory to start the shell in
+    #[clap(default_value = ".", verbatim_doc_comment)]
+    pub dir: PathBuf,
+
+    /// Shell to start
+    ///
+    /// Defaults to $SHELL
+    #[clap(verbatim_doc_comment, long, short = 's')]
+    pub shell: Option<String>,
+}
+
+impl En {
+    pub fn run(self) -> eyre::Result<()> {
+        let settings = Settings::get();
+        settings.ensure_experimental("en")?;
+
+        env::set_current_dir(&self.dir)?;
+        let shell = self.shell.or(env::var("SHELL").ok()).unwrap_or("sh".into());
+        let command = vec!["sh".into(), "-c".into(), OsString::from(shell)];
+
+        Exec {
+            tool: vec![],
+            raw: false,
+            jobs: None,
+            c: None,
+            command: Some(command),
+        }
+        .run()
+    }
+}
+
+static AFTER_LONG_HELP: &str = color_print::cstr!(
+    r#"<bold><underline>Examples:</underline></bold>
+
+    $ <bold>mise en .</bold>
+    $ <bold>node -v</bold>
+    v20.0.0
+
+    Skip loading bashrc:
+    $ <bold>mise en -s "bash --norc"</bold>
+
+    Skip loading zshrc:
+    $ <bold>mise en -s "zsh -f"</bold>
+"#
+);

src/cli/mod.rs

@@ -20,6 +20,7 @@ mod current;
 mod deactivate;
 mod direnv;
 mod doctor;
+mod en;
 mod env;
 pub mod exec;
 mod external;
@@ -159,6 +160,7 @@ pub enum Commands {
     Deactivate(deactivate::Deactivate),
     Direnv(direnv::Direnv),
     Doctor(doctor::Doctor),
+    En(en::En),
     Env(env::Env),
     Exec(exec::Exec),
     Generate(generate::Generate),
@@ -219,6 +221,7 @@ impl Commands {
             Self::Deactivate(cmd) => cmd.run(),
             Self::Direnv(cmd) => cmd.run(),
             Self::Doctor(cmd) => cmd.run(),
+            Self::En(cmd) => cmd.run(),
             Self::Env(cmd) => cmd.run(),
             Self::Exec(cmd) => cmd.run(),
             Self::Generate(cmd) => cmd.run(),

xtasks/fig/src/mise.ts

@@ -834,6 +834,36 @@ const completionSpec: Fig.Spec = {
             ],
             "description": "Check mise installation for possible problems"
         },
+        {
+            "name": [
+                "en"
+            ],
+            "description": "[experimental] starts a new shell with the mise environment built from the current configuration",
+            "options": [
+                {
+                    "name": [
+                        "-s",
+                        "--shell"
+                    ],
+                    "description": "Shell to start",
+                    "isRepeatable": false,
+                    "args": {
+                        "name": "shell",
+                        "isOptional": false,
+                        "isVariadic": false
+                    }
+                }
+            ],
+            "args": [
+                {
+                    "name": "dir",
+                    "description": "Directory to start the shell in",
+                    "isOptional": true,
+                    "isVariadic": false,
+                    "template": "folders"
+                }
+            ]
+        },
         {
             "name": [
                 "env",