Merge VSync and VRR fixes for combined testing

tests/test_metal_vsync.py

@@ -0,0 +1,139 @@
+"""Exercise the patched presentation policy and CGL call order without a GPU."""
+from pathlib import Path
+import shutil
+import subprocess
+import tempfile
+import unittest
+import test_runtime_compatibility as sources
+
+
+@unittest.skipUnless(shutil.which('c++'), 'C++ compiler required')
+class MetalVSyncChecks(unittest.TestCase):
+    patched = sources.CompatibilityChecks.patched
+
+    def test_explicit_vsync_is_scoped_to_each_cgl_context(self):
+        source = self.patched('darling', 'src/frameworks/OpenGL/OpenGL.c')
+        methods = '\n'.join(sources.function(source, name) for name in ('CGLFlushDrawable', 'CGLSetParameter'))
+        fixture = r'''
+#include <cassert>
+#include <cstdio>
+using GLint=int;
+using CGLError=int;
+using CGLContextParameter=int;
+using EGLBoolean=int;
+constexpr int kCGLNoError=0, kCGLBadContext=1, kCGLBadState=2, kCGLBadAddress=3, kCGLBadValue=4;
+constexpr int kCGLCPSwapInterval=1;
+struct Context { int egl_display=1, egl_surface=1, swap_interval=1, swap_interval_requested=0; };
+using CGLContextObj=Context*;
+static Context* current;
+static int display=1, applied=-1;
+static bool fail=false;
+static int swapInterval(int, int value) { if(fail) return 0; applied=value; return 1; }
+static auto p_eglSwapInterval=swapInterval;
+static int p_eglSwapBuffers(int,int) { return 1; }
+static Context* CGLGetCurrentContext() { return current; }
+''' + methods + r'''
+int main() {
+    Context a, b;
+    current=&a;
+    int interval=1;
+    assert(CGLSetParameter(&a,kCGLCPSwapInterval,&interval)==0 && applied==1);
+    CGLFlushDrawable(&a); assert(applied==1);
+    current=&b;
+    CGLFlushDrawable(&b); assert(applied==0); // Another window retains its default.
+    current=&a;
+    interval=0;
+    assert(CGLSetParameter(&a,kCGLCPSwapInterval,&interval)==0 && applied==0);
+    interval=1;
+    assert(CGLSetParameter(&a,kCGLCPSwapInterval,&interval)==0 && applied==1);
+    current=&b; fail=true;
+    assert(CGLSetParameter(&b,kCGLCPSwapInterval,&interval)==kCGLBadValue);
+    assert(!b.swap_interval_requested); // Failed requests must not change policy.
+    fail=false; CGLFlushDrawable(&b); assert(applied==0);
+    assert(CGLFlushDrawable(nullptr)==kCGLBadContext);
+}
+'''
+        self.run_cpp(fixture)
+
+    def test_nested_layers_toggles_windows_and_context_failures(self):
+        source = self.patched('cocotron', 'QuartzCore/CALayerContext.m')
+        policy = sources.function(source, 'metalSwapInterval')
+        # Translate only Objective-C message/iteration syntax; compile the actual
+        # policy and flush body against inert layer and CGL fixtures.
+        policy = policy.replace('[[layer class] isSubclassOfClass: [CAMetalLayerInternal class]]', 'layer->metal')
+        policy = policy.replace('[(CAMetalLayer *)layer displaySyncEnabled]', 'layer->sync')
+        policy = policy.replace('for (CALayer *child in layer.sublayers)', 'for (CALayer *child : layer->children)')
+        flush = source.split('- (void) flush {', 1)[1].split('\n}\n', 1)[0]
+        fixture = r'''
+#include <cassert>
+#include <vector>
+using GLint = int;
+using CGLContextObj = int;
+constexpr int kCGLNoError = 0, kCGLCPSwapInterval = 1;
+constexpr int NULL_CONTEXT = 0;
+struct CALayer { bool metal=false, sync=true; std::vector<CALayer*> children; };
+struct Context { int interval=-2, swaps=0; } contexts[3];
+static int current=2, attached=0;
+static bool fail=false, skip=false;
+static int CGLGetCurrentContext() { return current; }
+static int CGLSetCurrentContext(int context) { current=context; return 0; }
+static int CGLContextMakeCurrentAndAttachToWindow(int context, int window) {
+    if(fail) return 1;
+    current=context; attached=window; return 0;
+}
+static int CGLSetParameter(int context, int parameter, const int* interval) {
+    assert(current==context && attached==context && parameter==kCGLCPSwapInterval);
+    contexts[context].interval=*interval; return 0;
+}
+static int CGLFlushDrawable(int context) {
+    assert(current==context && attached==context);
+    ++contexts[context].swaps; return 0;
+}
+static bool skipLocalRender(CALayer*, int) { return skip; }
+'''
+        fixture += policy
+        fixture += '\nstruct Window { int _glContext=1, _cglWindow=1, _frame=0; CALayer* _layer; void flush() {'
+        fixture += flush.replace('NULL', 'NULL_CONTEXT').replace('_frame.size', '_frame') + '\n} };\n'
+        fixture += r'''
+int main() {
+    CALayer root, container, metal, other;
+    metal.metal=other.metal=true;
+    root.children={&container}; container.children={&metal};
+    assert(metalSwapInterval(&root)==1);
+    Window a{1,1,0,&root};
+    a.flush(); assert(contexts[1].interval==1 && current==2);
+    metal.sync=false;
+    a.flush(); assert(contexts[1].interval==0 && current==2);
+    container.children.push_back(&other);
+    a.flush(); assert(contexts[1].interval==1);
+    other.sync=false;
+    a.flush(); assert(contexts[1].interval==0);
+    CALayer plain;
+    assert(metalSwapInterval(&plain)==-1);
+    Window b{2,2,0,&plain};
+    b.flush(); assert(contexts[2].interval==-2);
+    other.sync=true;
+    a.flush(); assert(contexts[1].interval==1 && contexts[2].interval==-2);
+    a._cglWindow=0;
+    int swaps=contexts[1].swaps;
+    a.flush(); assert(contexts[1].swaps==swaps);
+    a._cglWindow=1; fail=true;
+    a.flush(); assert(contexts[1].swaps==swaps && current==2);
+    fail=false; skip=true;
+    a.flush(); assert(contexts[1].swaps==swaps);
+    skip=false; current=0;
+    a.flush(); assert(current==0);
+    current=1; a.flush(); assert(current==1);
+    root.children.clear();
+    assert(metalSwapInterval(&root)==-1);
+}
+'''
+        self.run_cpp(fixture)
+
+    def run_cpp(self, fixture):
+        with tempfile.TemporaryDirectory() as directory:
+            path = Path(directory)
+            (path/'check.cpp').write_text(fixture)
+            result = subprocess.run(['c++', '-std=c++17', str(path/'check.cpp'), '-o', str(path/'check')], capture_output=True, text=True)
+            self.assertEqual(result.returncode, 0, result.stderr)
+            subprocess.run([str(path/'check')], check=True, timeout=10)