BubbleTea Code Review
Quick Reference
CRITICAL: Avoid False Positives
Read elm-architecture.md first! The most common review mistake is flagging correct patterns as bugs.
NOT Issues (Do NOT Flag These)
| Pattern | Why It's Correct |
|---|
return m, m.loadData() | tea.Cmd is returned immediately; runtime executes async |
Value receiver on Update() | Standard BubbleTea pattern; model returned by value |
Nested m.child, cmd = m.child.Update(msg) | Normal component composition |
Helper functions returning tea.Cmd | Creates command descriptor, no I/O in Update |
tea.Batch(cmd1, cmd2) | Commands execute concurrently by runtime |
ACTUAL Issues (DO Flag These)
| Pattern | Why It's Wrong |
|---|
os.ReadFile() in Update | Blocks UI thread |
http.Get() in Update | Network I/O blocks |
time.Sleep() in Update | Freezes UI |
<-channel in Update (blocking) | May block indefinitely |
huh.Form.Run() in Update | Blocking call |
Review Checklist
Architecture
- No blocking I/O in Update() (file, network, sleep)
- Helper functions returning
tea.Cmd are NOT flagged as blocking - Commands used for all async operations
Model & Update
- Model is immutable (Update returns new model, not mutates)
- Init returns proper initial command (or nil)
- Update handles all expected message types
- WindowSizeMsg handled for responsive layout
- tea.Batch used for multiple commands
- tea.Quit used correctly for exit
View & Styling
- View is a pure function (no side effects)
- Lipgloss styles defined once, not in View
- Key bindings use key.Matches with help.KeyMap
Components
- Sub-component updates propagated correctly
- Bubbles components initialized with dimensions
- Huh forms embedded via Update loop (not Run())
Critical Patterns
Model Must Be Immutable
// BAD - mutates model
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
m.items = append(m.items, newItem) // mutation!
return m, nil
}
// GOOD - returns new model
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
newItems := make([]Item, len(m.items)+1)
copy(newItems, m.items)
newItems[len(m.items)] = newItem
m.items = newItems
return m, nil
}
Commands for Async/IO
// BAD - blocking in Update
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
data, _ := os.ReadFile("config.json") // blocks UI!
m.config = parse(data)
return m, nil
}
// GOOD - use commands
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
return m, loadConfigCmd()
}
func loadConfigCmd() tea.Cmd {
return func() tea.Msg {
data, err := os.ReadFile("config.json")
if err != nil {
return errMsg{err}
}
return configLoadedMsg{parse(data)}
}
}
Styles Defined Once
// BAD - creates new style each render
func (m Model) View() string {
style := lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("205"))
return style.Render("Hello")
}
// GOOD - define styles at package level or in model
var titleStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("205"))
func (m Model) View() string {
return titleStyle.Render("Hello")
}
When to Load References
Review Questions
- Is Update() free of blocking I/O? (NOT: "is the cmd helper blocking?")
- Is the model immutable in Update?
- Are Lipgloss styles defined once, not in View?
- Is WindowSizeMsg handled for resizing?
- Are key bindings documented with help.KeyMap?
- Are Bubbles components sized correctly?
