feat: add support for xonsh (#2807)

* feat: add support for xonsh

* xonsh: add STARSHIP_SESSION_KEY

* xonsh: implement STARSHIP_SESSION_KEY in xonsh

* docs: mention tcsh, elvish, and nu in more places

* xonsh: change STARSHIP_SESSION_KEY implementation

See https://github.com/starship/starship/pull/2807#discussion_r667064149

* xonsh: fix jobs implementation

* xonsh: do not silently discard stderr from starship

13 files changed, 99 insertions, 5 deletions

diff --git a/README.md b/README.md
index 0e78fcfaa..819c2d3e1 100644
--- a/README.md
+++ b/README.md
@@ -251,6 +251,15 @@ shown below. Can't see yours? Have a look at the [extra platform instructions](h
    # ~/.tcshrc
 
    eval `starship init tcsh`
+
+   #### Xonsh
+
+   Add the following to the end of `~/.xonshrc`:
+
+   ```sh
+   # ~/.xonshrc
+
+   execx($(starship init xonsh))
    ```
 
    #### Nushell
diff --git a/docs/.vuepress/config.js b/docs/.vuepress/config.js
index 92249c3b6..679e4bb93 100644
--- a/docs/.vuepress/config.js
+++ b/docs/.vuepress/config.js
@@ -50,13 +50,13 @@ module.exports = {
   head: [
     ["link", { rel: "icon", href: "/icon.png" }],
     ["meta", { property: "og:title", content: "Starship: Cross-Shell Prompt" }],
-    ["meta", { property: "og:description", content: "Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, and Powershell."}],
+    ["meta", { property: "og:description", content: "Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, Tcsh, Elvish, Nu, Xonsh, and Powershell."}],
     ["meta", { property: "og:type", content: "website" }],
     ["meta", { property: "og:url", content: "https://starship.rs/" }],
     ["meta", { property: "og:image", content: "https://starship.rs/icon.png" }],
     ["meta", { name: "twitter:card", content: "summary"}],
     ["meta", { name: "twitter:title", content: "Starship: Cross-Shell Prompt"}],
-    ["meta", { name: "twitter:description", content: "Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, and Powershell."}],
+    ["meta", { name: "twitter:description", content: "Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, Tcsh, Elvish, Nu, Xonsh, and Powershell."}],
     ["meta", { name: "twitter:image", content: "https://starship.rs/icon.png"}],
     ["meta", { name: "twitter:alt", content: "Starship: Cross-Shell Prompt"}],
   ],
diff --git a/docs/README.md b/docs/README.md
index 9ba9a4ae8..4014bfc2b 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -16,7 +16,7 @@ footer: ISC Licensed | Copyright © 2019-present Starship Contributors
 
 # Used for the description meta tag, for SEO
 metaTitle: "Starship: Cross-Shell Prompt"
-description: Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, and PowerShell.
+description: Starship is the minimal, blazing fast, and extremely customizable prompt for any shell! Shows the information you need, while staying sleek and minimal. Quick installation available for Bash, Fish, ZSH, Ion, Tcsh, Elvish, Nu, Xonsh, and PowerShell.
 ---
 
 <div class="center">
@@ -106,6 +106,7 @@ description: Starship is the minimal, blazing fast, and extremely customizable p
 
    eval $(starship init ion)
    ```
+
    #### Elvish
 
    ::: warning
@@ -130,7 +131,7 @@ description: Starship is the minimal, blazing fast, and extremely customizable p
    eval `starship init tcsh`
    ```
 
-    #### Nushell
+   #### Nushell
 
    ::: warning
    This will change in the future.
@@ -147,3 +148,13 @@ description: Starship is the minimal, blazing fast, and extremely customizable p
    ]
    prompt = "starship_prompt"
    ```
+
+   #### Xonsh
+
+   Add the following to the end of `~/.xonshrc`:
+
+   ```sh
+   # ~/.xonshrc
+
+   execx($(starship init xonsh))
+   ```
diff --git a/docs/config/README.md b/docs/config/README.md
index 635eff5ff..01c305fe1 100644
--- a/docs/config/README.md
+++ b/docs/config/README.md
@@ -2587,6 +2587,7 @@ To enable it, set `disabled` to `false` in your configuration file.
 | `ion_indicator`        | `ion`         | A format string used to represent ion.                       |
 | `elvish_indicator`     | `esh`         | A format string used to represent elvish.                    |
 | `tcsh_indicator`       | `tsh`         | A format string used to represent tcsh.                      |
+| `xonsh_indicator`      | `xsh`         | A format string used to represent xonsh.                     |
 | `unknown_indicator`    |               | The default value to be displayed when the shell is unknown. |
 | `format`               | `$indicator ` | The format for the module.                                   |
 | `disabled`             | `true`        | Disables the `shell` module.                                 |
diff --git a/install/install.sh b/install/install.sh
index 9ae5722b0..06d97d59f 100755
--- a/install/install.sh
+++ b/install/install.sh
@@ -456,4 +456,10 @@ info "Please follow the steps for your shell to complete the installation:
   Add the following to the end of ${BOLD}~/.tcshrc${NO_COLOR}:
 
       eval \`starship init tcsh\`
+
+  ${BOLD}${UNDERLINE}Xonsh${NO_COLOR}
+  Add the following to the end of ${BOLD}~/.xonshrc${NO_COLOR}:
+
+      execx($(starship init xonsh))
+
 "
diff --git a/snapcraft.yaml b/snapcraft.yaml
index dd19ada44..7dcf73435 100644
--- a/snapcraft.yaml
+++ b/snapcraft.yaml
@@ -42,6 +42,12 @@ description: |
 
   `Invoke-Expression (&starship init powershell)`
 
+  ### Xonsh
+
+  Add the following to the end of ~/.xonshrc:
+
+  execx($(starship init xonsh))
+
 grade: stable
 confinement: strict
 
diff --git a/src/bug_report.rs b/src/bug_report.rs
index 28a9bb720..5a2ed061c 100644
--- a/src/bug_report.rs
+++ b/src/bug_report.rs
@@ -212,6 +212,7 @@ fn get_config_path(shell: &str) -> Option<PathBuf> {
             "zsh" => Some(".zshrc"),
             "elvish" => Some(".elvish/rc.elv"),
             "tcsh" => Some(".tcshrc"),
+            "xonsh" => Some(".xonshrc"),
             _ => None,
         }
         .map(|path| home_dir.join(path))
diff --git a/src/configs/shell.rs b/src/configs/shell.rs
index 2f0fc6d15..818130ae3 100644
--- a/src/configs/shell.rs
+++ b/src/configs/shell.rs
@@ -14,6 +14,7 @@ pub struct ShellConfig<'a> {
     pub elvish_indicator: &'a str,
     pub tcsh_indicator: &'a str,
     pub nu_indicator: &'a str,
+    pub xonsh_indicator: &'a str,
     pub unknown_indicator: &'a str,
     pub disabled: bool,
 }
@@ -30,6 +31,7 @@ impl<'a> Default for ShellConfig<'a> {
             elvish_indicator: "esh",
             tcsh_indicator: "tsh",
             nu_indicator: "nu",
+            xonsh_indicator: "xsh",
             unknown_indicator: "",
             disabled: true,
         }
diff --git a/src/context.rs b/src/context.rs
index df88636a8..d6d518533 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -257,6 +257,7 @@ impl<'a> Context<'a> {
             "elvish" => Shell::Elvish,
             "tcsh" => Shell::Tcsh,
             "nu" => Shell::Nu,
+            "xonsh" => Shell::Xonsh,
             _ => Shell::Unknown,
         }
     }
@@ -494,6 +495,7 @@ pub enum Shell {
     Elvish,
     Tcsh,
     Nu,
+    Xonsh,
     Unknown,
 }
 
diff --git a/src/init/mod.rs b/src/init/mod.rs
index 893a063c7..2450d7ac6 100644
--- a/src/init/mod.rs
+++ b/src/init/mod.rs
@@ -168,6 +168,10 @@ pub fn init_stub(shell_name: &str) -> io::Result<()> {
             starship.sprint_posix()?
         ),
         "nu" => print_script(NU_INIT, &StarshipPath::init()?.sprint_posix()?),
+        "xonsh" => print!(
+            r#"execx($({} init xonsh --print-full-init))"#,
+            starship.sprint_posix()?
+        ),
         _ => {
             let quoted_arg = shell_words::quote(shell_basename);
             println!(
@@ -181,6 +185,7 @@ pub fn init_stub(shell_name: &str) -> io::Result<()> {
                  * tcsh\\n\
                  * zsh\\n\
                  * nu\\n\
+                 * xonsh\\n\
                  \\n\
                  Please open an issue in the starship repo if you would like to \
                  see support for %s:\\nhttps://github.com/starship/starship/issues/new\\n\\n\" {0} {0}",
@@ -204,6 +209,7 @@ pub fn init_main(shell_name: &str) -> io::Result<()> {
         "ion" => print_script(ION_INIT, &starship_path.sprint()?),
         "elvish" => print_script(ELVISH_INIT, &starship_path.sprint_posix()?),
         "tcsh" => print_script(TCSH_INIT, &starship_path.sprint_posix()?),
+        "xonsh" => print_script(XONSH_INIT, &starship_path.sprint_posix()?),
         _ => {
             println!(
                 "printf \"Shell name detection failed on phase two init.\\n\
@@ -251,6 +257,8 @@ const TCSH_INIT: &str = include_str!("starship.tcsh");
 
 const NU_INIT: &str = include_str!("starship.nu");
 
+const XONSH_INIT: &str = include_str!("starship.xsh");
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/init/starship.xsh b/src/init/starship.xsh
new file mode 100644
index 000000000..64439d203
--- /dev/null
+++ b/src/init/starship.xsh
@@ -0,0 +1,17 @@
+import uuid
+
+
+def starship_prompt():
+    last_cmd = __xonsh__.history[-1] if __xonsh__.history else None
+    status = last_cmd.rtn if last_cmd else 0
+    # I believe this is equivalent to xonsh.jobs.get_next_job_number() for our purposes,
+    # but we can't use that function because of https://gitter.im/xonsh/xonsh?at=60e8832d82dd9050f5e0c96a
+    jobs = sum(1 for job in __xonsh__.all_jobs.values() if job['obj'] and job['obj'].poll() is None)
+    duration = round((last_cmd.ts[1] - last_cmd.ts[0]) * 1000) if last_cmd else 0
+    # The `| cat` is a workaround for https://github.com/xonsh/xonsh/issues/3786. See https://github.com/starship/starship/pull/2807#discussion_r667316323.
+    return $(::STARSHIP:: prompt --status=@(status) --jobs=@(jobs) --cmd-duration=@(duration) | cat)
+
+
+$PROMPT = starship_prompt
+$STARSHIP_SHELL = "xonsh"
+$STARSHIP_SESSION_KEY = uuid.uuid4().hex
diff --git a/src/main.rs b/src/main.rs
index f1bce8fe6..e1dff67d5 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -43,7 +43,7 @@ fn main() {
     let shell_arg = Arg::with_name("shell")
         .value_name("SHELL")
         .help(
-            "The name of the currently running shell\nCurrently supported options: bash, zsh, fish, powershell, ion, elvish, tcsh, nu",
+            "The name of the currently running shell\nCurrently supported options: bash, zsh, fish, powershell, ion, elvish, tcsh, nu, xonsh",
         )
         .required(true);
 
diff --git a/src/modules/shell.rs b/src/modules/shell.rs
index d8a5f8e0b..0b141ec8a 100644
--- a/src/modules/shell.rs
+++ b/src/modules/shell.rs
@@ -25,6 +25,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
                     Shell::Elvish => Some(config.elvish_indicator),
                     Shell::Tcsh => Some(config.tcsh_indicator),
                     Shell::Nu => Some(config.nu_indicator),
+                    Shell::Xonsh => Some(config.xonsh_indicator),
                     Shell::Unknown => Some(config.unknown_indicator),
                 },
                 _ => None,
@@ -37,6 +38,7 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
                 "ion_indicator" => Some(Ok(config.ion_indicator)),
                 "elvish_indicator" => Some(Ok(config.elvish_indicator)),
                 "tcsh_indicator" => Some(Ok(config.tcsh_indicator)),
+                "xonsh_indicator" => Some(Ok(config.xonsh_indicator)),
                 "unknown_indicator" => Some(Ok(config.unknown_indicator)),
                 _ => None,
             })
@@ -280,6 +282,35 @@ mod tests {
     }
 
     #[test]
+    fn test_xonsh_default_format() {
+        let expected = Some(format!("{} ", "xsh"));
+        let actual = ModuleRenderer::new("shell")
+            .shell(Shell::Xonsh)
+            .config(toml::toml! {
+                [shell]
+                disabled = false
+            })
+            .collect();
+
+        assert_eq!(expected, actual);
+    }
+
+    #[test]
+    fn test_xonsh_custom_format() {
+        let expected = Some(format!("{} ", Color::Cyan.bold().paint("xonsh")));
+        let actual = ModuleRenderer::new("shell")
+            .shell(Shell::Xonsh)
+            .config(toml::toml! {
+                [shell]
+                xonsh_indicator = "[xonsh](bold cyan)"
+                disabled = false
+            })
+            .collect();
+
+        assert_eq!(expected, actual);
+    }
+
+    #[test]
     fn test_custom_format_conditional_indicator_match() {
         let expected = Some(format!("{} ", "B"));
         let actual = ModuleRenderer::new("shell")