swiftui-sheet-item-fixer

name

swiftui-sheet-item-fixer

description

Find and fix SwiftUI presentation race patterns where `.sheet(isPresented:)`, `.fullScreenCover(isPresented:)`, or `.popover(isPresented:)` depends on optional selected data and can render nil on first presentation. Use when a codebase has optional selection state plus separate presentation booleans, `if let` guards inside presentation closures, or delayed/async state updates that present with stale data.

SwiftUI Sheet Item Fixer

Scan SwiftUI code for optional-data presentation races and migrate safe cases to item-driven presentation APIs.

Workflow

1. Run the candidate scanner from the repo root:

python3 "$CODEX_HOME/skills/swiftui-sheet-item-fixer/scripts/find_optional_presentation_candidates.py" .

2. Prioritize findings where all three are true:

• .sheet(isPresented:) (or fullScreenCover / popover) is used.
• The presentation closure contains if let over a selected optional.
• A tap/action path sets selected data and presentation bool separately.

3. Convert safe matches to item-based presentation:

• Replace .sheet(isPresented: $showingX) with .sheet(item: $selectedX).
• Remove fallback else UI for nil-only race handling.
• Stop toggling the presentation boolean in handlers; assign selected item only.

4. Ensure presented item type conforms to Identifiable (stable id).
5. Rebuild and test after edits.

Conversion Rules

Use this canonical transformation when the sheet depends on selected data:

@State private var selectedThing: Thing?
@State private var showingThing = false

.sheet(isPresented: $showingThing) {
    if let thing = selectedThing {
        ThingDetailView(thing: thing)
    } else {
        Text("Error")
    }
}

Button {
    selectedThing = thing
    showingThing = true
}

Convert to:

@State private var selectedThing: Thing?

.sheet(item: $selectedThing) { thing in
    ThingDetailView(thing: thing)
}

Button {
    selectedThing = thing
}

Dismiss item-based presentation by setting selectedThing = nil when needed.

Safety Checks Before Editing

• Keep isPresented when no associated data is required.
• Keep isPresented when timing is intentionally decoupled from selection.
• Do not auto-convert when the optional is derived/computed rather than owned state.
• Keep @MainActor correctness for UI state updates in async contexts.

Validation

Run project commands (adjust scheme/destination when needed):

xcodebuild -list -project PokemonAnalyzer.xcodeproj
xcodebuild -scheme "PokemonAnalyzer" -destination "platform=iOS Simulator,name=iPhone 15" -configuration Debug build
xcodebuild -scheme "PokemonAnalyzer" -destination "platform=iOS Simulator,name=iPhone 15" test