feat(accessibility): implement core helpers

Author: Kyle-Ye

Sources/OpenSwiftUICore/Accessibility/AccessibilityCore.swift

@@ -3,10 +3,17 @@
 //  OpenSwiftUICore
 //
 //  Audited for 6.5.4
-//  Status: TODO
+//  Status: Complete
+
+public import Foundation
+import OpenSwiftUI_SPI
+
+// MARK: - AccessibilityCore
 
 package enum AccessibilityCore {}
 
+// MARK: - _ViewInputs/_GraphInputs + needsAccessibility
+
 extension _GraphInputs {
     package var needsAccessibility: Bool {
         get { options.contains(.needsAccessibility) }
@@ -21,25 +28,99 @@ extension _ViewInputs {
     }
 }
 
+// MARK: - WithinAccessibilityRotor
+
 package struct WithinAccessibilityRotor: ViewInputBoolFlag {
-    package init() {}
+    package init() {
+        _openSwiftUIEmptyStub()
+    }
 }
 
 extension _ViewInputs {
     @inline(__always)
     package var withinAccessibilityRotor: Bool {
-        needsAccessibility && self[WithinAccessibilityRotor.self]
+        get { self[WithinAccessibilityRotor.self] }
+        set { self[WithinAccessibilityRotor.self] = newValue }
+    }
+}
+
+// MARK: - PlatformAccessibilityElementProtocol
+
+@_spi(ForOpenSwiftUIOnly)
+@available(OpenSwiftUI_v6_0, *)
+#if canImport(ObjectiveC)
+@objc
+#endif
+public protocol PlatformAccessibilityElementProtocol: NSObjectProtocol {
+    #if os(macOS)
+    @objc dynamic var knownRepresentedElement: PlatformAccessibilityElement { get }
+    @objc dynamic var rotorOwnerElement: PlatformAccessibilityElement { get }
+    #endif
+}
+
+// MARK: - PlatformAccessibilityElement
+
+@_spi(ForOpenSwiftUIOnly)
+@available(OpenSwiftUI_v6_0, *)
+public typealias PlatformAccessibilityElement = NSObject & PlatformAccessibilityElementProtocol
+
+// MARK: - NSObject + PlatformAccessibilityElementProtocol
+
+@_spi(ForOpenSwiftUIOnly)
+@available(OpenSwiftUI_v6_0, *)
+extension NSObject: PlatformAccessibilityElementProtocol {
+    #if canImport(ObjectiveC)
+    @objc
+    #endif
+    dynamic open var knownRepresentedElement: PlatformAccessibilityElement {
+        self
+    }
+
+    #if canImport(ObjectiveC)
+    @objc
+    #endif
+    dynamic open var rotorOwnerElement: PlatformAccessibilityElement {
+        self
+    }
+}
+
+// MARK: - AccessibilityLayoutRole
+
+package enum AccessibilityLayoutRole: Hashable {
+    case stack
+    case grid
+}
+
+// MARK: - Locale.bcp47LanguageCode
+
+extension Locale {
+    package var bcp47LanguageCode: String? {
+        guard let languageCode = language.languageCode?.identifier,
+              !languageCode.isEmpty else {
+            return nil
+        }
+        return language.maximalIdentifier
     }
 }
 
-// TODO
+// MARK: - AccessibilityCore + description
 
 extension AccessibilityCore {
     package static func description(
         for symbolName: String,
         in environment: EnvironmentValues
     ) -> String? {
-        _openSwiftUIUnimplementedWarning()
-        return nil
+        #if canImport(Darwin)
+        let description = soft_AXSSAccessibilityDescriptionForSymbolName(
+            symbolName,
+            environment.locale.identifier
+        )
+        guard !description.isEmpty else {
+            return nil
+        }
+        return description.capitalized(with: environment.locale)
+        #else
+        _openSwiftUIPlatformUnimplementedFailure()
+        #endif
     }
 }

Sources/OpenSwiftUICore/Accessibility/PlatformAccessibilityElement.swift

@@ -0,0 +1,28 @@
+//
+//  AccessibilitySharedSupport.h
+//  OpenSwiftUI_SPI
+//
+//  Audited for 6.5.4
+//  Status: Complete
+
+#ifndef AccessibilitySharedSupport_h
+#define AccessibilitySharedSupport_h
+
+#include "OpenSwiftUIBase.h"
+
+#if OPENSWIFTUI_TARGET_OS_DARWIN
+
+#import <Foundation/Foundation.h>
+
+OPENSWIFTUI_EXTERN_C_BEGIN
+OPENSWIFTUI_ASSUME_NONNULL_BEGIN
+
+OPENSWIFTUI_EXPORT
+NSString *soft_AXSSAccessibilityDescriptionForSymbolName(NSString *symbolName, NSString *localeIdentifier);
+
+OPENSWIFTUI_ASSUME_NONNULL_END
+OPENSWIFTUI_EXTERN_C_END
+
+#endif /* OPENSWIFTUI_TARGET_OS_DARWIN */
+
+#endif /* AccessibilitySharedSupport_h */

Sources/OpenSwiftUI_SPI/Overlay/Accessibility/AccessibilitySharedSupport.h

@@ -0,0 +1,64 @@
+//
+//  AccessibilitySharedSupport.m
+//  OpenSwiftUI_SPI
+//
+//  Audited for 6.5.4
+//  Status: Complete
+
+#include "AccessibilitySharedSupport.h"
+
+#if OPENSWIFTUI_TARGET_OS_DARWIN
+
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <string.h>
+
+void abort_report_np(const char *format, ...) __attribute__((noreturn, format(printf, 1, 2)));
+
+static void *AccessibilitySharedSupportLibraryCore(char **error) {
+    static void *frameworkLibrary;
+    if (frameworkLibrary == NULL) {
+        frameworkLibrary = dlopen(
+            "/System/Library/PrivateFrameworks/AccessibilitySharedSupport.framework/AccessibilitySharedSupport",
+            RTLD_LAZY | RTLD_LOCAL
+        );
+        if (frameworkLibrary == NULL) {
+            *error = strdup(dlerror());
+        }
+    }
+    return frameworkLibrary;
+}
+
+static void *AccessibilitySharedSupportLibrary(void) {
+    char *error = NULL;
+    void *frameworkLibrary = AccessibilitySharedSupportLibraryCore(&error);
+    if (frameworkLibrary == NULL) {
+        abort_report_np("%s", error);
+    }
+    if (error != NULL) {
+        free(error);
+    }
+    return frameworkLibrary;
+}
+
+static void *getAXSSAccessibilityDescriptionForSymbolNameSymbolLoc(void) {
+    static void *ptr;
+    if (ptr == NULL) {
+        ptr = dlsym(
+            AccessibilitySharedSupportLibrary(),
+            "AXSSAccessibilityDescriptionForSymbolName"
+        );
+    }
+    return ptr;
+}
+
+NSString *soft_AXSSAccessibilityDescriptionForSymbolName(NSString *symbolName, NSString *localeIdentifier) {
+    NSString *(*function)(NSString *, NSString *) =
+        (NSString *(*)(NSString *, NSString *))getAXSSAccessibilityDescriptionForSymbolNameSymbolLoc();
+    if (function == NULL) {
+        abort_report_np("%s", dlerror());
+    }
+    return function(symbolName, localeIdentifier);
+}
+
+#endif /* OPENSWIFTUI_TARGET_OS_DARWIN */