Restore profile-first interactive launches

crates/lazaret-client/src/cli.rs

@@ -12,7 +12,9 @@ use crate::state::{StateCommand, StateOperation};
     name = "lazaret",
     version,
     about = "Run development tools in an isolated agent sandbox",
-    long_about = "Run development tools in an isolated gVisor sandbox while keeping workspace editing, persistent tool state, controlled network access, and developer-approved host actions available."
+    long_about = "Run development tools in an isolated gVisor sandbox while keeping workspace editing, persistent tool state, controlled network access, and developer-approved host actions available.",
+    override_usage = "lazaret <PROFILE> [OPTIONS] [-- <COMMAND>...]\n       lazaret <COMMAND>",
+    after_help = "Launch a profile directly with `lazaret PROFILE`. Add `-- COMMAND...` to override the default /bin/bash environment entry."
 )]
 struct Cli {
     #[command(subcommand)]
@@ -34,8 +36,8 @@ enum PublicCommand {
 struct RunArguments {
     #[command(flatten)]
     domain: DomainArguments,
-    /// Command and arguments to run inside the sandbox.
-    #[arg(last = true, required = true, num_args = 1.., value_name = "COMMAND")]
+    /// Command and arguments to run instead of the default `/bin/bash`.
+    #[arg(last = true, num_args = 1.., value_name = "COMMAND")]
     command: Vec<OsString>,
 }
 
@@ -112,17 +114,14 @@ pub fn parse(
     arguments: impl IntoIterator<Item = OsString>,
     current_workspace: PathBuf,
 ) -> Result<Command, clap::Error> {
+    let arguments = expand_profile_launch(arguments);
     let cli = Cli::try_parse_from(std::iter::once(OsString::from("lazaret")).chain(arguments))?;
     Ok(match cli.command {
         PublicCommand::Run(arguments) => Command::Run(ClientCommand {
             profile: arguments.domain.profile,
             workspace: arguments.domain.workspace.unwrap_or(current_workspace),
             configuration: arguments.domain.config,
-            argv: arguments
-                .command
-                .into_iter()
-                .map(std::os::unix::ffi::OsStringExt::into_vec)
-                .collect(),
+            argv: command_argv(arguments.command),
         }),
         PublicCommand::State { operation } => {
             Command::State(state_command(operation, current_workspace))
@@ -130,6 +129,29 @@ pub fn parse(
     })
 }
 
+fn expand_profile_launch(arguments: impl IntoIterator<Item = OsString>) -> Vec<OsString> {
+    let mut arguments = arguments.into_iter().collect::<Vec<_>>();
+    if arguments.first().is_some_and(|first| {
+        first != "run"
+            && first != "state"
+            && first.to_str().is_some_and(|first| !first.starts_with('-'))
+    }) {
+        arguments.insert(0, OsString::from("--profile"));
+        arguments.insert(0, OsString::from("run"));
+    }
+    arguments
+}
+
+fn command_argv(command: Vec<OsString>) -> Vec<Vec<u8>> {
+    if command.is_empty() {
+        return vec![b"/bin/bash".to_vec()];
+    }
+    command
+        .into_iter()
+        .map(std::os::unix::ffi::OsStringExt::into_vec)
+        .collect()
+}
+
 fn state_command(operation: StateArguments, current_workspace: PathBuf) -> StateCommand {
     let (operation, domain, machine, yes, scope) = match operation {
         StateArguments::List(arguments) => (

crates/lazaret-client/tests/cli_contract.rs

@@ -233,11 +233,31 @@ fn unsupported_host_and_configuration_errors_keep_their_cause() {
 }
 
 #[test]
-fn command_line_requires_an_explicit_profile_and_preserves_command_bytes() {
+fn command_line_accepts_profile_entry_and_preserves_explicit_command_bytes() {
+    let parsed =
+        lazaret_client::cli::parse(["agent"].map(OsString::from), PathBuf::from("/current"))
+            .unwrap();
+    let lazaret_client::cli::Command::Run(parsed) = parsed else {
+        panic!("expected run command");
+    };
+    assert_eq!(parsed.profile, "agent");
+    assert_eq!(parsed.workspace, PathBuf::from("/current"));
+    assert_eq!(parsed.configuration, None);
+    assert_eq!(parsed.argv, [b"/bin/bash".to_vec()]);
+
+    let parsed = lazaret_client::cli::parse(
+        ["run", "--profile", "state"].map(OsString::from),
+        PathBuf::from("/current"),
+    )
+    .unwrap();
+    let lazaret_client::cli::Command::Run(parsed) = parsed else {
+        panic!("expected run command");
+    };
+    assert_eq!(parsed.profile, "state");
+    assert_eq!(parsed.argv, [b"/bin/bash".to_vec()]);
+
     let parsed = lazaret_client::cli::parse(
         [
-            "run",
-            "--profile",
             "agent",
             "--workspace",
             "/project",
@@ -305,6 +325,8 @@ fn public_help_explains_commands_and_options() {
             &["--help"][..],
             &[
                 "Run development tools in an isolated gVisor sandbox",
+                "Usage: lazaret <PROFILE>",
+                "lazaret PROFILE",
                 "run",
                 "state",
             ][..],
@@ -314,7 +336,7 @@ fn public_help_explains_commands_and_options() {
             &[
                 "Agent profile to use",
                 "Project directory to share",
-                "Command and arguments to run",
+                "default `/bin/bash`",
             ],
         ),
         (
@@ -347,11 +369,10 @@ fn public_help_explains_commands_and_options() {
 }
 
 #[test]
-fn clap_rejects_missing_profile_command_and_ambiguous_reset_scope() {
+fn clap_rejects_missing_profile_and_ambiguous_reset_scope() {
     let workspace = PathBuf::from("/current");
     for arguments in [
         vec!["run", "--", "tool"],
-        vec!["run", "--profile", "agent"],
         vec!["state", "reset", "--profile", "agent"],
         vec![
             "state",