iOS release builds compile again: dismiss_keyboard leaves the debug-only block (MOB-504)

.github/workflows/test.yml

@@ -137,6 +137,22 @@ jobs:
         # themselves. Same toolchain as the clang-format step.
         run: make -C test/native run
 
+      - name: Install Erlang (erl_nif.h for the iOS NIF compile)
+        run: brew install erlang
+
+      - name: iOS NIF compiles in debug and release (MOB-504)
+        # mob 0.9.26 shipped a release nif_funcs entry for a function defined
+        # only in debug builds. Only compiling the release variant catches that.
+        # The Swift sources need the iOS 26 SDK (glassEffect), and the runner's
+        # default Xcode is older, so pick its newest Xcode 26.
+        run: |
+          xcode=$(ls -d /Applications/Xcode_26*.app 2>/dev/null | sort -V | tail -1)
+          if [ -z "$xcode" ]; then
+            echo "::error::no Xcode 26 on this runner"; ls -d /Applications/Xcode*.app; exit 1
+          fi
+          echo "Using $xcode"
+          DEVELOPER_DIR="$xcode/Contents/Developer" make -C test/native ios-nif
+
       - name: Install swiftlint
         run: brew install swiftlint
 

CHANGELOG.md

@@ -47,12 +47,22 @@ Full module documentation: [hexdocs.pm/mob](https://hexdocs.pm/mob).
   window only when that window's session is gone (`{:mob_scene, :replaced,
   ...}`), and a kept window whose session is discarded stops
   (`{:mob_scene, :discarded, id}`). The by-tag press helpers
-  (`press_in/3`, `press_out/3`, `hold/4`) take `scene:` too. Opt in with
+  (`press_in/3`, `press_out/3`, `hold/4`) take `scene:` too. The reload
+  `mix mob.deploy` sends to `:mob_screen` after a hot push repaints every
+  window, not only the one whose router holds the name. Opt in with
   `config :mob_dev, multi_window: true` (mob_dev#114 stamps
   `UIApplicationSupportsMultipleScenes`). Needs a native rebuild. Run on the
   iPad and iPhone simulators, not yet on a physical iPad. See
   `decisions/2026-10-02-one-router-per-window-scene.md`.
 
+### Fixed
+- **iOS release builds compile again (MOB-504).** In 0.9.26, `nif_dismiss_keyboard` and
+  the first-responder walk it uses were defined inside the debug-only test-harness block
+  (`#if !MOB_RELEASE`), while their `nif_funcs` entries were not, so every iOS release
+  build failed with "use of undeclared identifier 'nif_dismiss_keyboard'". Both now sit
+  outside the harness block. CI now compiles `ios/mob_nif.m` in debug, release, and
+  release with `MOB_ENABLE_SCREENSHOT` (`make -C test/native ios-nif`).
+
 ## [0.9.26] - 2026-10-24
 
 ### Added

RELEASE.md

@@ -192,6 +192,9 @@ Per-repo extras:
   repo that ships the scanner. The `hex_deps` layer applies to
   mob_dev itself; the gradle / swift / bundled_runtime layers no-op
   (mob_dev has no native surface).
+- **`mob`**: also run `make -C test/native ios-nif` on a Mac. It compiles
+  `ios/mob_nif.m` in its release variants, which nothing else builds
+  before an app's own release build (MOB-504).
 - **`mob_new`**: generator tests need `MOB_DIR=/Users/kevin/code/mob`
   when running from a worktree; the path resolver looks for `mob`
   alongside the project.

ios/mob_nif.m

@@ -5840,6 +5840,75 @@ void mob_notify_set_screen_pid(ErlNifPid pid) {
     });
 }
 
+// Shared with the debug-only harness below (delete_backward, key_press), but
+// outside its guard: dismiss_keyboard is public API and ships in release
+// builds (MOB-504).
+static id find_first_responder_in(UIView *view) {
+    if (view.isFirstResponder)
+        return view;
+    for (UIView *sub in view.subviews) {
+        id fr = find_first_responder_in(sub);
+        if (fr)
+            return fr;
+    }
+    return nil;
+}
+
+// ─── dismiss_keyboard/0,1 — take the keyboard down from the BEAM ─────────────
+//
+// Resigns the first responder found in a visible window — the walk
+// delete_backward and key_press use — which is the view the keyboard is up
+// for. Nothing focused is not an error; the keyboard is already down.
+//
+// Which windows (MOB-245): dismiss_keyboard/1 takes the scene id of the
+// calling screen and looks only in that window scene. dismiss_keyboard/0 is
+// the unbound primary's: it looks only in the primary's window (tap set 0),
+// and nowhere while that window is detached and another is attached, so one
+// window's handler never closes another window's keyboard. With no scene
+// attached at all it looks in every connected scene, as before scenes.
+//
+// Waits (bounded) for the main thread to do it, so it is IO_BOUND. The caller
+// is a handler that usually re-renders too, and MobTextField adopts a new
+// `value:` only once it is no longer focused. Queued fire-and-forget, the
+// handler's render reached the field while SwiftUI still had it focused, and
+// the value assigned next to the dismiss was dropped in most runs after an
+// edit (iPhone Air simulator, iOS 27.0). Returning once the resign has run
+// queues the re-render behind it, and the value then landed every time.
+// {error, timeout} if the main thread did not get to it within 2 s.
+
+static ERL_NIF_TERM nif_dismiss_keyboard(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+    NSString *sceneId = argc == 1 ? mob_scene_id_from_term(env, argv[0]) : nil;
+    if (argc == 1 && !sceneId)
+        return enif_make_badarg(env);
+    dispatch_semaphore_t done = dispatch_semaphore_create(0);
+    dispatch_async(dispatch_get_main_queue(), ^{
+      BOOL everywhere = !sceneId && mob_scene_attached_count() == 0;
+      UIWindowScene *only = sceneId ? mob_window_scene_for(sceneId) : mob_primary_window_scene();
+      id fr = nil;
+      for (UIScene *scene in [UIApplication sharedApplication].connectedScenes) {
+          if (![scene isKindOfClass:[UIWindowScene class]])
+              continue;
+          if (!everywhere && scene != only)
+              continue;
+          for (UIWindow *win in [(UIWindowScene *)scene windows]) {
+              if (win.isHidden)
+                  continue;
+              fr = find_first_responder_in(win);
+              if (fr)
+                  break;
+          }
+          if (fr)
+              break;
+      }
+      [fr resignFirstResponder];
+      dispatch_semaphore_signal(done);
+    });
+    dispatch_time_t deadline = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC));
+    if (dispatch_semaphore_wait(done, deadline) != 0)
+        return enif_make_tuple2(env, enif_make_atom(env, "error"), enif_make_atom(env, "timeout"));
+    return enif_make_atom(env, "ok");
+}
+
 // ════════════════════════════════════════════════════════════════════════════
 // TEST HARNESS — compiled out of release builds (MOB_RELEASE).
 // ════════════════════════════════════════════════════════════════════════════
@@ -7737,17 +7806,6 @@ static ERL_NIF_TERM nif_tap_xy(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv
 #endif
 }
 
-static id find_first_responder_in(UIView *view) {
-    if (view.isFirstResponder)
-        return view;
-    for (UIView *sub in view.subviews) {
-        id fr = find_first_responder_in(sub);
-        if (fr)
-            return fr;
-    }
-    return nil;
-}
-
 // ─── delete_backward/0 — delete one character behind the cursor ──────────────
 //
 // Calls deleteBackward: on the current first responder. Equivalent to pressing
@@ -7786,61 +7844,6 @@ static ERL_NIF_TERM nif_delete_backward(ErlNifEnv *env, int argc, const ERL_NIF_
                             enif_make_atom(env, "no_first_responder"));
 }
 
-// ─── dismiss_keyboard/0,1 — take the keyboard down from the BEAM ─────────────
-//
-// Resigns the first responder found in a visible window — the walk
-// delete_backward and key_press use — which is the view the keyboard is up
-// for. Nothing focused is not an error; the keyboard is already down.
-//
-// Which windows (MOB-245): dismiss_keyboard/1 takes the scene id of the
-// calling screen and looks only in that window scene. dismiss_keyboard/0 is
-// the unbound primary's: it looks only in the primary's window (tap set 0),
-// and nowhere while that window is detached and another is attached, so one
-// window's handler never closes another window's keyboard. With no scene
-// attached at all it looks in every connected scene, as before scenes.
-//
-// Waits (bounded) for the main thread to do it, so it is IO_BOUND. The caller
-// is a handler that usually re-renders too, and MobTextField adopts a new
-// `value:` only once it is no longer focused. Queued fire-and-forget, the
-// handler's render reached the field while SwiftUI still had it focused, and
-// the value assigned next to the dismiss was dropped in most runs after an
-// edit (iPhone Air simulator, iOS 27.0). Returning once the resign has run
-// queues the re-render behind it, and the value then landed every time.
-// {error, timeout} if the main thread did not get to it within 2 s.
-
-static ERL_NIF_TERM nif_dismiss_keyboard(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
-    NSString *sceneId = argc == 1 ? mob_scene_id_from_term(env, argv[0]) : nil;
-    if (argc == 1 && !sceneId)
-        return enif_make_badarg(env);
-    dispatch_semaphore_t done = dispatch_semaphore_create(0);
-    dispatch_async(dispatch_get_main_queue(), ^{
-      BOOL everywhere = !sceneId && mob_scene_attached_count() == 0;
-      UIWindowScene *only = sceneId ? mob_window_scene_for(sceneId) : mob_primary_window_scene();
-      id fr = nil;
-      for (UIScene *scene in [UIApplication sharedApplication].connectedScenes) {
-          if (![scene isKindOfClass:[UIWindowScene class]])
-              continue;
-          if (!everywhere && scene != only)
-              continue;
-          for (UIWindow *win in [(UIWindowScene *)scene windows]) {
-              if (win.isHidden)
-                  continue;
-              fr = find_first_responder_in(win);
-              if (fr)
-                  break;
-          }
-          if (fr)
-              break;
-      }
-      [fr resignFirstResponder];
-      dispatch_semaphore_signal(done);
-    });
-    dispatch_time_t deadline = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC));
-    if (dispatch_semaphore_wait(done, deadline) != 0)
-        return enif_make_tuple2(env, enif_make_atom(env, "error"), enif_make_atom(env, "timeout"));
-    return enif_make_atom(env, "ok");
-}
-
 // ─── key_press/1 — send a special key to the focused text input ───────────────
 //
 // Accepts an atom:

lib/mob/router.ex

@@ -559,6 +559,22 @@ defmodule Mob.Router do
     {:noreply, state}
   end
 
+  # mob_dev sends a deploy's reload as a bare message to :mob_screen, which
+  # names one window's router. Every window repaints with the new code: this
+  # router's screens, and every other window's router (MOB-245). Asked from a
+  # separate process so this router never waits on Mob.Scenes.
+  def handle_info(:__mob_hot_reload__, state) do
+    me = self()
+
+    spawn(fn ->
+      for {_scene, router} <- Mob.Scenes.list(),
+          router != me,
+          do: GenServer.cast(router, :__mob_hot_reload__)
+    end)
+
+    handle_cast(:__mob_hot_reload__, state)
+  end
+
   # Anything else addressed to :mob_screen — device events, notifications,
   # plugin messages — belongs to the screen the user is looking at.
   def handle_info(message, state) do

lib/mob/test.ex

@@ -16,7 +16,7 @@ defmodule Mob.Test do
       Mob.Test.tree(node)                 #=> %{type: :column, ...}
       Mob.Test.find(node, "Save")         #=> [{[0, 2], %{...}}]
       Mob.Test.inspect(node)              #=> %{screen: ..., assigns: ..., tree: ...}
-      Mob.Test.screens(node)              #=> [{nil, MyApp.HomeScreen, #PID<...>}]
+      Mob.Test.screens(node)              #=> [{"8A3F…", MyApp.HomeScreen, #PID<...>}]
 
       # Interaction
       Mob.Test.tap(node, :increment)      # tap a button by tag

test/mob/scenes_test.exs

@@ -396,6 +396,18 @@ defmodule Mob.ScenesTest do
       refute_receive {:alert, _, _}, 50
     end
 
+    test "a deploy's reload, sent to :mob_screen, repaints every window" do
+      boot(["A"])
+      connect("B")
+      flush_frames()
+
+      # What mob_dev's deployer sends after a hot push.
+      send(:mob_screen, :__mob_hot_reload__)
+
+      assert_receive {:frame, :default, nil, %{"props" => %{"text" => "home 0"}}}
+      assert_receive {:frame, "B", "B", %{"props" => %{"text" => "home 0"}}}
+    end
+
     test "the back gesture steps the WebView history of its own window only" do
       boot(["A"])
       connect("W")

test/native/Makefile

@@ -1,6 +1,8 @@
 # Native-side checks that can run on the host (no simulator, no XCTest target).
 #
-#   make run    build + run everything here
+#   make run      build + run everything here
+#   make ios-nif  compile ios/mob_nif.m in its debug and release variants
+#                 (needs Xcode and Erlang; see ios_nif_compile.sh)
 #   make clean
 #
 # Each test file's header says what it does and does not cover.
@@ -11,10 +13,13 @@ LDFLAGS ?= -framework Foundation
 
 BINS := frame_registry_test dist_port_test dist_cookie_test stored_queue_test init_args_test node_host_test code_versions_test erts_dir_test
 
-.PHONY: run clean
+.PHONY: run ios-nif clean
 run: $(BINS)
 	@for b in $(BINS); do echo "== $$b"; ./$$b || exit 1; done
 
+ios-nif:
+	./ios_nif_compile.sh
+
 frame_registry_test: frame_registry_test.m
 	$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
 

test/native/ios_nif_compile.sh

@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+# Compiles ios/mob_nif.m (syntax only) in each build variant an app can ship:
+# debug, release, and release with the screenshot opt-in. Most of the file
+# sits behind `#if !MOB_RELEASE`, and only a real compile catches a release
+# table entry that names a debug-only function: MOB-504 shipped in mob 0.9.26
+# because nothing built the release variant.
+#
+#   test/native/ios_nif_compile.sh        (from the repo root, or `make -C test/native ios-nif`)
+#
+# Needs Xcode (the iphoneos SDK) and an Erlang install for erl_nif.h; set
+# ERL_INCLUDE to use another include dir. The Swift sources are compiled once
+# to produce the MobApp-Swift.h header mob_nif.m imports.
+set -euo pipefail
+
+cd "$(dirname "$0")/../.."
+out=$(mktemp -d)
+trap 'rm -rf "$out"' EXIT
+
+sdk=$(xcrun --sdk iphoneos --show-sdk-path)
+target=arm64-apple-ios17.0
+erl_include=${ERL_INCLUDE:-$(erl -noshell -eval \
+  'io:format("~s", [filename:join([code:root_dir(), "erts-" ++ erlang:system_info(version), "include"])]), halt().')}
+
+xcrun swiftc -sdk "$sdk" -target "$target" -module-name MobApp -parse-as-library \
+  -import-objc-header ios/MobDemo-Bridging-Header.h -I"$erl_include" -Iios \
+  -emit-module -emit-module-path "$out/MobApp.swiftmodule" \
+  -emit-objc-header-path "$out/MobApp-Swift.h" ios/*.swift
+
+status=0
+for flags in "" "-DMOB_RELEASE=1" "-DMOB_RELEASE=1 -DMOB_ENABLE_SCREENSHOT"; do
+  echo "== mob_nif.m ${flags:-(debug)}"
+  # shellcheck disable=SC2086 # $flags is a list of separate -D options
+  xcrun clang -fsyntax-only -fobjc-arc -fmodules -x objective-c \
+    -target "$target" -isysroot "$sdk" -I"$erl_include" -Iios -I"$out" \
+    $flags ios/mob_nif.m || status=1
+done
+exit $status