worktree-switching

Worktree Switching

Sidecar supports seamless switching between git worktrees. When switching:

1. All plugins are stopped, reinitialized with the new WorkDir, and restarted
2. Per-worktree state (active plugin, sidebar selections) is saved/restored
3. Project-specific themes are applied
4. If a worktree is deleted externally, sidecar gracefully falls back to main

Core Mechanism

Project Switching

Worktree switching uses Model.switchProject() in internal/app/model.go:

m.switchProject(worktreePath)

This triggers in order:

1. Save active plugin for old WorkDir
2. Update m.ui.WorkDir to new path
3. Apply resolved theme for new path
4. Call registry.Reinit(newWorkDir) -- stops all plugins, updates context, reinits all
5. Send WindowSizeMsg to all plugins for layout recalculation
6. Restore saved active plugin for new WorkDir
7. Show toast notification

Registry Reinitialization

Registry.Reinit() in internal/plugin/registry.go:

func (r *Registry) Reinit(newWorkDir string) []tea.Cmd {
    // Stop all plugins (reverse order)
    for i := len(r.plugins) - 1; i >= 0; i-- {
        r.safeStop(r.plugins[i])
    }
    // Update context
    r.ctx.WorkDir = newWorkDir
    // Reinit all plugins
    for _, p := range r.plugins {
        r.safeInit(p)
    }
    // Collect and return start commands
    return startCmds
}

Plugin Responsibilities on Worktree Switch

Handle Reinitialization Cleanly

Your plugin will be stopped and reinitialized on worktree switch. Ensure:

1. Stop() releases all resources (watchers, goroutines, channels)
2. Init(ctx) resets state and reads from new ctx.WorkDir
3. Start() kicks off fresh async work for the new context

func (p *Plugin) Stop() {
    p.stopOnce.Do(func() {
        if p.watcher != nil {
            p.watcher.Close()
        }
        close(p.done)
    })
}

func (p *Plugin) Init(ctx *plugin.Context) error {
    p.ctx = ctx
    p.items = nil            // Reset state
    p.stopOnce = sync.Once{} // Reset stop guard
    p.done = make(chan struct{})
    return nil
}