Reorganize Swift files more hierarchically (#267)

Package.swift

@@ -37,7 +37,7 @@ let package = Package(
             path: "Support/Sources/WindowsRuntime",
             exclude: [
                 "CMakeLists.txt",
-                "ProjectedTypes/Core/Readme.md",
+                "ProjectedTypes/Readme.md",
                 "ProjectedTypes/WindowsFoundation/Readme.md",
             ]),
         .testTarget(

Support/Sources/COM/COMError+createErrorInfo.swift

@@ -0,0 +1,23 @@
+import COM_ABI
+
+extension COMError {
+    /// Creates an instance of `ICreateErrorInfo`.
+    public static func createErrorInfo() throws -> ICreateErrorInfo {
+        var createErrorInfo = ICreateErrorInfoProjection.abiDefaultValue
+        defer { ICreateErrorInfoProjection.release(&createErrorInfo) }
+        try COMError.fromABI(SWRT_CreateErrorInfo(&createErrorInfo))
+        return try NullResult.unwrap(ICreateErrorInfoProjection.toSwift(createErrorInfo))
+    }
+
+    /// Creates an instance of `IErrorInfo` with prepopulated fields.
+    public static func createErrorInfo(guid: GUID? = nil, source: String? = nil, description: String?,
+            helpFile: String? = nil, helpContext: UInt32? = nil) throws -> IErrorInfo {
+        let errorInfo = try createErrorInfo()
+        if let guid { try errorInfo.setGUID(guid) }
+        if let source { try errorInfo.setSource(source) }
+        if let description { try errorInfo.setDescription(description) }
+        if let helpFile { try errorInfo.setHelpFile(helpFile) }
+        if let helpContext { try errorInfo.setHelpContext(helpContext) }
+        return try errorInfo.queryInterface(IErrorInfoProjection.self)
+    }
+}

Support/Sources/COM/COMError.swift

@@ -38,7 +38,7 @@ public struct COMError: COMErrorProtocol, CustomStringConvertible {
     }
 
     public init(hresult: HResult, description: String?) {
-        self.init(hresult: hresult, errorInfo: description.flatMap { try? createErrorInfo(description: $0) })
+        self.init(hresult: hresult, errorInfo: description.flatMap { try? Self.createErrorInfo(description: $0) })
     }
 
     public var description: String {

Support/Sources/WindowsRuntime/ArrayProjection.swift → Support/Sources/WindowsRuntime/ProjectedTypes/ArrayProjection.swift

@@ -1,5 +1,6 @@
 import COM
 
+/// Projects a WinRT array to a Swift array.
 public enum ArrayProjection<ElementProjection: ABIProjection>: ABIProjection {
     // WinRT does not have a distinct representation for null and empty
     public typealias SwiftValue = [ElementProjection.SwiftValue]

Support/Sources/WindowsRuntime/ProjectedTypes/Core/IRestrictedErrorInfo.swift → Support/Sources/WindowsRuntime/ProjectedTypes/IRestrictedErrorInfo.swift

@@ -3,13 +3,26 @@ import COM
 public typealias IRestrictedErrorInfo = any IRestrictedErrorInfoProtocol
 public protocol IRestrictedErrorInfoProtocol: IUnknownProtocol {
     func getErrorDetails(
-        description: inout String?,
-        error: inout HResult,
-        restrictedDescription: inout String?,
-        capabilitySid: inout String?) throws
+        _ description: inout String?,
+        _ error: inout HResult,
+        _ restrictedDescription: inout String?,
+        _ capabilitySid: inout String?) throws
     var reference: String? { get throws }
 }
 
+extension IRestrictedErrorInfoProtocol {
+    var errorDetails: (description: String?, error: HResult, restrictedDescription: String?, capabilitySid: String?) {
+        get throws {
+            var description: String? = nil
+            var error: HResult = .fail
+            var restrictedDescription: String? = nil
+            var capabilitySid: String? = nil
+            try getErrorDetails(&description, &error, &restrictedDescription, &capabilitySid)
+            return (description, error, restrictedDescription, capabilitySid)
+        }
+    }
+}
+
 import WindowsRuntime_ABI
 
 public enum IRestrictedErrorInfoProjection: COMProjection {
@@ -28,10 +41,10 @@ public enum IRestrictedErrorInfoProjection: COMProjection {
 
     private final class Import: COMImport<IRestrictedErrorInfoProjection>, IRestrictedErrorInfoProtocol {
         func getErrorDetails(
-                description: inout String?,
-                error: inout HResult,
-                restrictedDescription: inout String?,
-                capabilitySid: inout String?) throws {
+                _ description: inout String?,
+                _ error: inout HResult,
+                _ restrictedDescription: inout String?,
+                _ capabilitySid: inout String?) throws {
             try _interop.getErrorDetails(&description, &error, &restrictedDescription, &capabilitySid)
         }
 

Support/Sources/WindowsRuntime/ProjectedTypes/Readme.md

@@ -0,0 +1 @@
+Defines Swift projections for core WinRT types, and COM types that support the Windows Runtime. Those types are defined in native idl or C++ headers rather than Windows Metadata files and cannot be generated.

Support/Sources/WindowsRuntime/WinRTError.swift

@@ -24,9 +24,13 @@ public struct WinRTError: COMErrorProtocol, CustomStringConvertible {
     }
 
     public var description: String {
-        let details = (try? restrictedErrorInfo?.details) ?? RestrictedErrorInfoDetails()
-        // RestrictedDescription contains the value reported in RoOriginateError
-        return details.restrictedDescription ?? details.description ?? hresult.description
+        if let restrictedErrorInfo {
+            let errorDetails = try? restrictedErrorInfo.errorDetails
+            if let restrictedDescription = errorDetails?.restrictedDescription { return restrictedDescription }
+            if let description = errorDetails?.description { return description }
+        }
+
+        return hresult.description
     }
 
     public func toABI(setErrorInfo: Bool = true) -> HResult.Value {
@@ -41,20 +45,12 @@ public struct WinRTError: COMErrorProtocol, CustomStringConvertible {
         guard hresult.isFailure else { return hresult }
 
         // Check for an associated IRestrictedErrorInfo
-        guard captureErrorInfo, let restrictedErrorInfo = try? Self.getRestrictedErrorInfo(matching: hresult) else {
+        guard captureErrorInfo,
+                let restrictedErrorInfo = try? Self.getRestrictedErrorInfo(matching: hresult),
+                (try? restrictedErrorInfo.errorDetails.error) == hresult else {
             throw WinRTError(hresult: hresult)
         }
 
-        // Ensure we didn't get a stale IRestrictedErrorInfo
-        var description: String? = nil
-        var error: HResult = .ok
-        var restrictedDescription: String? = nil
-        var capabilitySid: String? = nil
-        try? restrictedErrorInfo.getErrorDetails(
-            description: &description, error: &error,
-            restrictedDescription: &restrictedDescription, capabilitySid: &capabilitySid)
-        guard error == hresult else { throw WinRTError(hresult: hresult) }
-
         // Append to the propagation context, if available.
         // See https://learn.microsoft.com/en-us/windows/win32/api/restrictederrorinfo/nf-restrictederrorinfo-ilanguageexceptionerrorinfo2-capturepropagationcontext
         if let languageExceptionErrorInfo = try? restrictedErrorInfo.queryInterface(ILanguageExceptionErrorInfoProjection.self) {