feat(builtins): implement suspend

brush-core/src/builtins.rs

@@ -49,6 +49,8 @@ mod return_;
 mod set;
 mod shift;
 mod shopt;
+#[cfg(unix)]
+mod suspend;
 mod test;
 mod times;
 mod trap;

brush-core/src/builtins/factory.rs

@@ -261,6 +261,8 @@ pub(crate) fn get_default_builtins(
         m.insert("printf".into(), builtin::<printf::PrintfCommand>());
         m.insert("shopt".into(), builtin::<shopt::ShoptCommand>());
         m.insert("source".into(), special_builtin::<dot::DotCommand>());
+        #[cfg(unix)]
+        m.insert("suspend".into(), builtin::<suspend::SuspendCommand>());
         m.insert("test".into(), builtin::<test::TestCommand>());
         m.insert("[".into(), builtin::<test::TestCommand>());
         m.insert("typeset".into(), builtin::<declare::DeclareCommand>());
@@ -284,7 +286,6 @@ pub(crate) fn get_default_builtins(
         m.insert("history".into(), builtin::<unimp::UnimplementedCommand>());
         m.insert("logout".into(), builtin::<unimp::UnimplementedCommand>());
         m.insert("readarray".into(), builtin::<unimp::UnimplementedCommand>());
-        m.insert("suspend".into(), builtin::<unimp::UnimplementedCommand>());
     }
 
     //

brush-core/src/builtins/suspend.rs

@@ -0,0 +1,33 @@
+use clap::Parser;
+use std::io::Write;
+
+use crate::{builtins, commands, error};
+
+/// Suspend the shell.
+#[derive(Parser)]
+pub(crate) struct SuspendCommand {
+    /// Force suspend login shells.
+    #[arg(short = 'f')]
+    force: bool,
+}
+
+impl builtins::Command for SuspendCommand {
+    async fn execute(
+        &self,
+        context: commands::ExecutionContext<'_>,
+    ) -> Result<builtins::ExitCode, error::Error> {
+        if context.shell.options.login_shell && !self.force {
+            writeln!(context.stderr(), "login shell cannot be suspended")?;
+            return Ok(builtins::ExitCode::InvalidUsage);
+        }
+
+        #[allow(clippy::cast_possible_truncation)]
+        #[allow(clippy::cast_possible_wrap)]
+        crate::sys::signal::kill_process(
+            std::process::id() as i32,
+            crate::traps::TrapSignal::Signal(nix::sys::signal::SIGSTOP),
+        )?;
+
+        Ok(builtins::ExitCode::Success)
+    }
+}