Automatic indentation

Author: ole

LayoutInspector/DebugLayout.swift

@@ -15,8 +15,8 @@ extension View {
     }
 
     /// Monitor the layout proposals and responses for this view and add them to the log.
-    func debugLayout(_ label: String, indent: Int = 0) -> some View {
-        DebugLayout(label: label, indent: indent) {
+    func debugLayout(_ label: String) -> some View {
+        DebugLayout(label: label) {
             self
         }
         .modifier(DebugLayoutSelectionHighlight(viewID: label))
@@ -26,13 +26,12 @@ extension View {
 /// A custom layout that adds the layout proposals and responses for a view to a log for display.
 struct DebugLayout: Layout {
     var label: String
-    var indent: Int
 
     func sizeThatFits(proposal: ProposedViewSize, subviews: Subviews, cache: inout ()) -> CGSize {
         assert(subviews.count == 1)
-        logLayoutStep(label, step: .proposal(proposal), indent: indent)
+        logLayoutStep(label, step: .proposal(proposal))
         let response = subviews[0].sizeThatFits(proposal)
-        logLayoutStep(label, step: .response(response), indent: indent)
+        logLayoutStep(label, step: .response(response))
         return response
     }
 

LayoutInspector/DebugLayoutLog.swift

@@ -1,21 +1,39 @@
 import SwiftUI
 
-func logLayoutStep(_ label: String, step: LogItem.Step, indent: Int) {
+func logLayoutStep(_ label: String, step: LogItem.Step) {
     DispatchQueue.main.async {
-        // Coalesce layout steps if the response follows immediately after the proposal
-        // for the same view.
-        //
-        // In this case, proposal and response can be shown in a single row in the log.
-        if var lastLogItem = LogStore.shared.log.last,
-           lastLogItem.label == label,
-           case .proposal(let proposal) = lastLogItem.step,
-           case .response(let response) = step
-        {
+        guard let prevEntry = LogStore.shared.log.last else {
+            // First log entry → start at indent 0.
+            LogStore.shared.log.append(LogItem(label: label, step: step, indent: 0))
+            return
+        }
+
+        var newEntry = LogItem(label: label, step: step, indent: prevEntry.indent)
+        let isSameView = prevEntry.label == label
+        switch (isSameView, prevEntry.step, step) {
+        case (true, .proposal(let prop), .response(let resp)):
+            // Response follows immediately after proposal for the same view.
+            // → We want to display them in a single row.
+            // → Coalesce both layout steps.
             LogStore.shared.log.removeLast()
-            lastLogItem.step = .proposalAndResponse(proposal: proposal, response: response)
-            LogStore.shared.log.append(lastLogItem)
-        } else {
-            LogStore.shared.log.append(.init(label: label, step: step, indent: indent))
+            newEntry = prevEntry
+            newEntry.step = .proposalAndResponse(proposal: prop, response: resp)
+            LogStore.shared.log.append(newEntry)
+
+        case (_, .proposal, .proposal):
+            // A proposal follows a proposal → nested view → increment indent.
+            newEntry.indent += 1
+            LogStore.shared.log.append(newEntry)
+
+        case (_, .response, .response),
+            (_, .proposalAndResponse, .response):
+            // A response follows a response → last child returns to parent → decrement indent.
+            newEntry.indent -= 1
+            LogStore.shared.log.append(newEntry)
+
+        default:
+            // Keep current indentation.
+            LogStore.shared.log.append(newEntry)
         }
     }
 }