link: cmux link seed push and seed clone, a Cloud project seed with the copy as fallback

cmux-tui/crates/cmux-tui-core/src/git_seed.rs

@@ -35,12 +35,28 @@ pub const GIT_SEED_COMMANDS: [&str; 2] = ["git.seed.start", "git.seed.status"];
 
 static SERVICE: OnceLock<GitSeedService> = OnceLock::new();
 
+/// Test seam, debug builds only: `CMUX_TEST_GIT_SEED_GITHUB=<absolute dir>`
+/// makes the daemon's seeds clone `https://github.com/OWNER/NAME.git` from
+/// `file://<dir>/OWNER/NAME.git`, with no GitHub path
+/// ([`GitSeedService::with_test_github`]). Release builds never read it.
+#[cfg(debug_assertions)]
+const TEST_GITHUB_VAR: &str = "CMUX_TEST_GIT_SEED_GITHUB";
+
 /// The seed owner, when this daemon serves `fs-v1` (it seeds under the same
 /// roots).
 #[must_use]
 pub fn installed() -> Option<&'static GitSeedService> {
     let fs = crate::fs_ops::installed()?;
-    Some(SERVICE.get_or_init(|| GitSeedService::new(fs.roots().clone())))
+    Some(SERVICE.get_or_init(|| {
+        #[cfg(debug_assertions)]
+        if let Some(dir) = std::env::var_os(TEST_GITHUB_VAR)
+            .map(std::path::PathBuf::from)
+            .filter(|dir| dir.is_absolute())
+        {
+            return GitSeedService::with_test_github(fs.roots().clone(), &dir);
+        }
+        GitSeedService::new(fs.roots().clone())
+    }))
 }
 
 /// The capability to advertise in `identify`, when served.

cmux-tui/crates/cmux-tui-core/src/git_seed/job.rs

@@ -183,6 +183,27 @@ impl GitSeedService {
         Self { roots, config, jobs: Mutex::new(Jobs::default()) }
     }
 
+    /// For tests (and the debug-only daemon seam in [`super::installed`]):
+    /// a service whose GitHub is the folder `github`, so
+    /// `https://github.com/OWNER/NAME.git` is cloned from
+    /// `file://<github>/OWNER/NAME.git`, with no credential. Nothing on the
+    /// wire reaches it.
+    #[doc(hidden)]
+    #[must_use]
+    pub fn with_test_github(roots: Roots, github: &std::path::Path) -> Self {
+        let local = format!("file://{}/", github.display());
+        let config = Config {
+            git: Git {
+                extra_config: vec![
+                    format!("url.{local}.insteadOf=https://github.com/"),
+                    "protocol.file.allow=always".into(),
+                ],
+            },
+            credentials: Some(vec![Credential::Anonymous]),
+        };
+        Self::with_config(roots, config)
+    }
+
     /// Runs `cmd` with the request object `params`.
     pub fn call(&self, cmd: &str, params: &Value) -> Result<Value, SeedRefusal> {
         match cmd {

cmux-tui/crates/cmux-tui/src/link/agent_cli.rs

@@ -65,12 +65,14 @@
 //! (`agent_session.host_unverified`) and gives the chat back. A replacement
 //! link keeps the socket path, so a rerun still resolves an unresolved move.
 //!
-//! `--sync push|pull --sync-socket LINK --sync-local LOCAL --sync-remote
+//! `--sync push|pull|seed --sync-socket LINK --sync-local LOCAL --sync-remote
 //! REMOTE`: once the chat is frozen (after the begin, before the receive), the
 //! pump copies its folder's last changes, `cmux link sync push LOCAL REMOTE`
-//! (Move to Cloud) or `cmux link sync pull LOCAL REMOTE` (Bring Back Local)
-//! over the machine link socket `LINK`. A chat moved mid-turn (`--interrupt`)
-//! made changes up to the freeze, after the caller's own sync; this takes
+//! (Move to Cloud), `cmux link seed push --since-last LOCAL REMOTE` (Move to
+//! Cloud of a folder `cmux link seed push` put there: a delta bundle, or a
+//! re-push of its copy) or `cmux link sync pull LOCAL REMOTE` (Bring Back
+//! Local) over the machine link socket `LINK`. A chat moved mid-turn
+//! (`--interrupt`) made changes up to the freeze, after the caller's own sync; this takes
 //! them along, so the turn goes on there with them (acpmux queues its
 //! continuation, cmuxterm-hq#5846 item 1). A sync that fails, or a pull that
 //! conflicts (`sync_conflict` with `conflicts`), gives the chat back. It runs
@@ -101,7 +103,7 @@ use record::{Record, Records};
 const USAGE: &str = "usage: cmux link agent move --from-socket LOCAL_DAEMON_SOCKET \
 --surface SURFACE_ID --to-socket REMOTE_CONNECT_SOCKET --cwd REMOTE_FOLDER [--interrupt] \
 [--ask-first] [--vm-kind KIND [--to-pid PID]] [--state-dir DIR] \
-[--sync push|pull --sync-socket LINK_SOCKET --sync-local LOCAL --sync-remote REMOTE]
+[--sync push|pull|seed --sync-socket LINK_SOCKET --sync-local LOCAL --sync-remote REMOTE]
   --to-socket: the local_socket of `cmux-tui remote connect --headless --json` for the \
 machine (its connection-snapshot event), not the machine link socket of `cmux link sync`";
 /// Bytes asked for per page (the daemon serves at most 4 MiB).
@@ -127,14 +129,22 @@ struct Args {
     sync: Option<Sync>,
 }
 
-/// `--sync push|pull --sync-socket --sync-local --sync-remote` (module docs).
+/// `--sync push|pull|seed --sync-socket --sync-local --sync-remote` (module docs).
 struct Sync {
-    pull: bool,
+    way: Way,
     socket: PathBuf,
     local: PathBuf,
     remote: String,
 }
 
+/// Which way `--sync` copies.
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum Way {
+    Push,
+    Pull,
+    Seed,
+}
+
 /// A move that failed, as its JSON line reports it.
 struct Failed {
     code: String,
@@ -254,8 +264,9 @@ fn parse(args: &[String]) -> Option<Args> {
             "--ask-first" => ask_first = true,
             "--sync" => {
                 sync = Some(match rest.next()?.as_str() {
-                    "push" => false,
-                    "pull" => true,
+                    "push" => Way::Push,
+                    "pull" => Way::Pull,
+                    "seed" => Way::Seed,
                     _ => return None,
                 });
             }
@@ -269,8 +280,8 @@ fn parse(args: &[String]) -> Option<Args> {
     // All four or none; the remote folder is absolute, as `cmux link sync` takes it.
     let sync = match (sync, sync_socket, sync_local, sync_remote) {
         (None, None, None, None) => None,
-        (Some(pull), Some(socket), Some(local), Some(remote)) if remote.starts_with('/') => {
-            Some(Sync { pull, socket, local, remote: remote.trim_end_matches('/').to_owned() })
+        (Some(way), Some(socket), Some(local), Some(remote)) if remote.starts_with('/') => {
+            Some(Sync { way, socket, local, remote: remote.trim_end_matches('/').to_owned() })
         }
         _ => return None,
     };
@@ -459,13 +470,28 @@ fn fresh(args: &Args, records: &Records) -> Result<Moved, Failed> {
 /// `--sync`'s copy of a frozen chat's folder (module docs).
 fn sync_frozen(sync: &Sync) -> Result<(), Failed> {
     use super::sync_cli::{self, Back};
-    if !sync.pull {
-        return sync_cli::push(&sync.socket, &sync.local, &sync.remote).map(|_| ()).map_err(|e| {
-            Failed::new(
-                sync_cli::push_failure_code(&e),
-                format!("the folder's last changes: {e:#}"),
-            )
-        });
+    match sync.way {
+        Way::Push => {
+            return sync_cli::push(&sync.socket, &sync.local, &sync.remote).map(|_| ()).map_err(
+                |e| {
+                    Failed::new(
+                        sync_cli::push_failure_code(&e),
+                        format!("the folder's last changes: {e:#}"),
+                    )
+                },
+            );
+        }
+        Way::Seed => {
+            return super::seed_cli::push_since_last(&sync.socket, &sync.local, &sync.remote)
+                .map(|_| ())
+                .map_err(|e| {
+                    Failed::new(
+                        super::seed_cli::failure_code(&e),
+                        format!("the folder's last changes: {e:#}"),
+                    )
+                });
+        }
+        Way::Pull => {}
     }
     match sync_cli::pull_into(&sync.socket, &sync.local, &sync.remote) {
         Back::Done(_) => Ok(()),

cmux-tui/crates/cmux-tui/src/link/mod.rs

@@ -11,9 +11,10 @@ mod dial;
 mod dial_cli;
 mod enrollment;
 mod ensure;
-// Not wired into start-chat yet; its CLI entry is `cmux link seed plan`.
+// `cmux link seed plan`; `cmux link seed push|clone` is [`seed_cli`].
 #[cfg_attr(not(test), allow(dead_code))]
 mod seed;
+mod seed_cli;
 mod start_chat_cli;
 mod sync_cli;
 // Wired into `serve` when Cloud hosts run the link (needs the TeamDO peer
@@ -119,6 +120,9 @@ pub(crate) fn run(args: &[String]) -> i32 {
         return sync_cli::run(&args[1..]);
     }
     if args.first().map(String::as_str) == Some("seed") {
+        if matches!(args.get(1).map(String::as_str), Some("push" | "clone")) {
+            return seed_cli::run(&args[1..]);
+        }
         return seed::run(&args[1..]);
     }
     // So do `agent` and `access`.