zed-industries/zed · critical

not implemented

Error message

not implemented

What it means

This is Rust's unimplemented!() macro: executing it panics with 'not implemented'. Session::set_ignore_breakpoints only implements propagation for a running local session (as_running() -> local.send_source_breakpoints); for every other state the code deliberately panics, with an adjacent todo acknowledging that propagation to downstream/upstream sessions was never written.

Source

Thrown at crates/project/src/debugger/session.rs:2009

        self.set_ignore_breakpoints(!self.ignore_breakpoints, cx)
    }

    pub(crate) fn set_ignore_breakpoints(
        &mut self,
        ignore: bool,
        cx: &mut App,
    ) -> Task<HashMap<Arc<Path>, anyhow::Error>> {
        if self.ignore_breakpoints == ignore {
            return Task::ready(HashMap::default());
        }

        self.ignore_breakpoints = ignore;

        if let Some(local) = self.as_running() {
            local.send_source_breakpoints(ignore, &self.breakpoint_store, cx)
        } else {
            // todo(debugger): We need to propagate this change to downstream sessions and send a message to upstream sessions
            unimplemented!()
        }
    }

    pub fn data_breakpoints(&self) -> impl Iterator<Item = &DataBreakpointState> {
        self.data_breakpoints.values()
    }

    pub fn exception_breakpoints(
        &self,
    ) -> impl Iterator<Item = &(ExceptionBreakpointsFilter, IsEnabled)> {
        self.exception_breakpoints.values()
    }

    pub fn toggle_exception_breakpoint(&mut self, id: &str, cx: &App) {
        if let Some((_, is_enabled)) = self.exception_breakpoints.get_mut(id) {
            *is_enabled = !*is_enabled;
            self.send_exception_breakpoints(cx);
        }

View on GitHub (pinned to bc538def45)

Solutions

1. As a user: restart the debug session, then toggle ignore-breakpoints again
2. As a caller: guard the call with the session's running state (as_running().is_some()) and skip when not running
3. Upstream fix: replace unimplemented!() with Task::ready(HashMap::default()) (flag already stored, synced on next launch) or propagate an Err instead of panicking

Example fix

// before
if let Some(local) = self.as_running() {
    local.send_source_breakpoints(ignore, &self.breakpoint_store, cx)
} else {
    unimplemented!()
}

// after
if let Some(local) = self.as_running() {
    local.send_source_breakpoints(ignore, &self.breakpoint_store, cx)
} else {
    // Flag is stored; it will be applied when a session next runs.
    Task::ready(HashMap::default())
}

// Only propagate the flag while a local session is actually running
let has_running = session.as_running().is_some();
if has_running && session.ignore_breakpoints() != ignore {
    session.set_ignore_breakpoints(ignore, cx);
}

fn can_sync_breakpoints(session: &debugger::Session) -> bool {
    // set_ignore_breakpoints only implements the running-local path;
    // everything else hits unimplemented!().
    session.as_running().is_some()
}

// Rust: this is a panic, not a Result — catch_unwind only as a last resort
use std::panic::{catch_unwind, AssertUnwindSafe};
let outcome = catch_unwind(AssertUnwindSafe(|| {
    session.set_ignore_breakpoints(ignore, cx)
}));
if outcome.is_err() {
    log::error!("set_ignore_breakpoints panicked; session not running?");
}

When it happens

Trigger: Calling set_ignore_breakpoints(ignore) with a new value while the session has no running local debug adapter — debuggee already terminated, session stopped/deferred before launch, or a remote/attached session — hits the else branch and panics.

Common situations: Toggling the breakpoints-enabled switch in the debugger UI right after the debuggee exits or before it starts; a race where the session stops between the ignore flag check and the as_running() call; scripted or extension-driven breakpoint toggles on non-running sessions.

Related errors

• output token limit reached
• message not found
• not supported
• cannot capture writable sandbox path `{}`
• cannot re-verify approved sandbox write grant `{}` (if the d

AI-assisted analysis of zed-industries/zed@bc538def45 (2026-08-16). Data as JSON: /api/errors/bc5615d30066d8d3. Report an issue: GitHub.