1 files changed, 29 insertions, 0 deletions

diff --git a/test/macos_e2e.swift b/test/macos_e2e.swift
index c076aebb..800e2d43 100644
--- a/test/macos_e2e.swift
+++ b/test/macos_e2e.swift
@@ -95,6 +95,8 @@ private final class Driver: PardesViewDelegate {
     private var observer: NSObjectProtocol?
     private var output = ""
     private var nextAnimationFrame: Date?
+    /// Where present() puts the pixels nobody reads.
+    private var presentationRep: NSBitmapImageRep?
 
     /// The script's own file name, for error messages.
     private let scriptName: String
@@ -219,6 +221,7 @@ private final class Driver: PardesViewDelegate {
         window?.contentView = nil
         window = nil
         view = nil
+        presentationRep = nil
         host.clipboard = nil
         host.woke = false
     }
@@ -336,6 +339,10 @@ private final class Driver: PardesViewDelegate {
 
     private func readFrame() -> Frame {
         let count = pardes_frame()
+        // The core has produced a frame; presenting it is this harness's half of
+        // the contract, and it has to happen AFTER the render rather than before
+        // — see present().
+        defer { present() }
         let cols = Int(pardes_frame_cols())
         let rows = Int(pardes_frame_rows())
         // -1 means hidden. Clamped to 0 rather than printed, which is what
@@ -396,6 +403,28 @@ private final class Driver: PardesViewDelegate {
             options: .regularExpression)
     }
 
+    /// Put the frame readFrame() just produced on screen — for a window that has
+    /// no screen, into a bitmap. draw(_:) is the only caller of
+    /// pardes_frame_presented, and this window is deliberately never ordered
+    /// front, so without this nothing here would ever present anything: the core
+    /// would owe a presentation for the rest of the script and correctly hold
+    /// every pointer gesture after the first layout change inert, addressing
+    /// pixels no backend had shown. The app pays the same debt on every pump
+    /// (AppDelegate.pump marks the view, AppKit's display cycle draws it).
+    ///
+    /// The rep is kept and reused rather than allocated per frame: this runs on
+    /// every poll slice, and cacheDisplay only needs somewhere to put pixels
+    /// nobody reads. `draw` makes its own, because it reads them.
+    private func present() {
+        guard let view, view.bounds.width >= 1, view.bounds.height >= 1 else { return }
+        let bounds = view.bounds
+        if presentationRep?.size != bounds.size {
+            presentationRep = view.bitmapImageRepForCachingDisplay(in: bounds)
+        }
+        guard let rep = presentationRep else { return }
+        view.cacheDisplay(in: bounds, to: rep)
+    }
+
     /// Render the view the way AppKit would and prove the CoreText pass put
     /// something on the screen. `snap` reads the core's cell buffer and would be
     /// perfectly happy with a draw(_:) that returned on its first line; this is