Compiler doesn't pass protocol conformance data

soumyamahunt · January 26, 2024, 7:12pm

Hi, I have developed MetaCodable, a library that generates Codable conformance implementation. Recently one issue got reported, debugging which I found out compiler isn't passing protocol conformance data to macro with some lines present.

The issue can be reproduced with this sample project, and removing following lines resolves the issue:

github.com

ashleydw/metacodable-min-ex/blob/c0bd383995ca3c12938f704b79429e2c9c7b0c9b/test/ContentView.swift#L6


      
          import SwiftUI
          import SwiftData
          
          struct ContentView: View {
              @Environment(\.modelContext) private var modelContext
              @Query private var items: [Item]
          
              var body: some View {
                  NavigationSplitView {
                      List {
                          ForEach(items) { item in
                              NavigationLink {
                                  Text("Item at \(item.title)")
                              } label: {
                                  Text(item.title)
                              }

github.com

ashleydw/metacodable-min-ex/blob/c0bd383995ca3c12938f704b79429e2c9c7b0c9b/test/ContentView.swift#L11-L18


      
          ForEach(items) { item in
              NavigationLink {
                  Text("Item at \(item.title)")
              } label: {
                  Text(item.title)
              }
          }
          .onDelete(perform: deleteItems)

github.com

ashleydw/metacodable-min-ex/blob/c0bd383995ca3c12938f704b79429e2c9c7b0c9b/test/ContentView.swift#L50


      
              private func addItem() {
                  withAnimation {
                      let newItem = Item(t: "title 1")
                      modelContext.insert(newItem)
                  }
              }
          
              private func deleteItems(offsets: IndexSet) {
                  withAnimation {
                      for index in offsets {
                          modelContext.delete(items[index])
                      }
                  }
              }
          }
          
          #Preview {
              ContentView()
                  .modelContainer(for: Item.self, inMemory: true)
          }

github.com

ashleydw/metacodable-min-ex/blob/c0bd383995ca3c12938f704b79429e2c9c7b0c9b/test/ContentView.swift#L58


      
                  withAnimation {
                      for index in offsets {
                          modelContext.delete(items[index])
                      }
                  }
              }
          }
          
          #Preview {
              ContentView()
                  .modelContainer(for: Item.self, inMemory: true)
          }

I am quite not sure why with these lines present compiler not passing the protocol conformance data, any help will be appreciated.