[PlaygroundLogger] Implemented support for the CustomPlaygroundDisplayConvertible protocol.

Implementations of `CustomPlaygroundDisplayConvertible` are now checked; the instance returned by `playgroundDescription` is sent back through the primary initializer.
This includes a super-basic test that this functionality works.

Author: cwakamo

PlaygroundLogger/PlaygroundLogger.xcodeproj/project.pbxproj

@@ -81,6 +81,9 @@
 		5E5FE50B202D13C800E28C3C /* PGLConcurrentMap.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E5FE50A202D13C800E28C3C /* PGLConcurrentMap.swift */; };
 		5ECE8F911FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5ECE8F901FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift */; };
 		5EE3867420352F3200D625F0 /* CGFloat+CustomOpaqueLoggable.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EE3867320352F3200D625F0 /* CGFloat+CustomOpaqueLoggable.swift */; };
+		5EF581532041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EF581512041384700AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift */; };
+		5EF581542041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EF581512041384700AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift */; };
+		5EF581552041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EF581512041384700AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift */; };
 		5EFE9193203F6CF900E21BAA /* LegacyPlaygroundLoggerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5ECE8F901FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift */; };
 		5EFE919B203F6DD700E21BAA /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EFE919A203F6DD700E21BAA /* AppDelegate.swift */; };
 		5EFE919D203F6DD700E21BAA /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5EFE919C203F6DD700E21BAA /* ViewController.swift */; };
@@ -247,6 +250,7 @@
 		5E5FE50A202D13C800E28C3C /* PGLConcurrentMap.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PGLConcurrentMap.swift; sourceTree = "<group>"; };
 		5ECE8F901FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LegacyPlaygroundLoggerTests.swift; sourceTree = "<group>"; };
 		5EE3867320352F3200D625F0 /* CGFloat+CustomOpaqueLoggable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "CGFloat+CustomOpaqueLoggable.swift"; sourceTree = "<group>"; };
+		5EF581512041384700AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CustomPlaygroundDisplayConvertibleTests.swift; sourceTree = "<group>"; };
 		5EFE9189203F6CC400E21BAA /* PlaygroundLoggerTests_iOS.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = PlaygroundLoggerTests_iOS.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		5EFE918D203F6CC400E21BAA /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		5EFE9198203F6DD700E21BAA /* PlaygroundLoggerTestHost_iOS.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = PlaygroundLoggerTestHost_iOS.app; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -366,6 +370,7 @@
 		5E2646341FB64876002DC6B6 /* PlaygroundLoggerTests */ = {
 			isa = PBXGroup;
 			children = (
+				5EF581512041384700AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift */,
 				5E5D777F2040BD7D00EBC3A9 /* LogPolicyTests.swift */,
 				5ECE8F901FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift */,
 			);
@@ -927,6 +932,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				5E5D77802040BD7D00EBC3A9 /* LogPolicyTests.swift in Sources */,
+				5EF581532041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */,
 				5ECE8F911FFCD2A70034D9BC /* LegacyPlaygroundLoggerTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -936,6 +942,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				5E5D77812040BD7D00EBC3A9 /* LogPolicyTests.swift in Sources */,
+				5EF581542041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */,
 				5EFE9193203F6CF900E21BAA /* LegacyPlaygroundLoggerTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -963,6 +970,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				5E5D77822040BD7D00EBC3A9 /* LogPolicyTests.swift in Sources */,
+				5EF581552041387C00AC14FE /* CustomPlaygroundDisplayConvertibleTests.swift in Sources */,
 				5EFE91D7203F6F8100E21BAA /* LegacyPlaygroundLoggerTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

PlaygroundLogger/PlaygroundLogger/LogEntry+Reflection.swift

@@ -34,9 +34,14 @@ extension LogEntry {
         // Returns either the passed-in type name/summary or the type name/summary of `instance`.
         var typeName: String { return passedInTypeName ?? normalizedName(of: type(of: instance)) }
         var summary: String { return passedInSummary ?? String(describing: instance) }
+
+        // For types which conform to the `CustomPlaygroundDisplayConvertible` protocol, get their custom representation and then run it back through the initializer.
+        if let customPlaygroundDisplayConvertible = instance as? CustomPlaygroundDisplayConvertible {
+            self = try .init(describing: customPlaygroundDisplayConvertible.playgroundDescription, name: name, typeName: typeName, summary: nil, policy: policy, currentDepth: currentDepth)
+        }
 
-        // For types which conform to the `CustomOpaqueLoggable` protocol, get their custom representation and construct an opaque log entry. (This is checked *second* so that user implementations of `CustomPlaygroundRepresentable` are honored over this framework's implementations of `CustomOpaqueLoggable`.)
-        if let customOpaqueLoggable = instance as? CustomOpaqueLoggable {
+        // For types which conform to the `CustomOpaqueLoggable` protocol, get their custom representation and construct an opaque log entry. (This is checked *second* so that user implementations of `CustomPlaygroundDisplayConvertible` are honored over this framework's implementations of `CustomOpaqueLoggable`.)
+        else if let customOpaqueLoggable = instance as? CustomOpaqueLoggable {
             // TODO: figure out when to set `preferBriefSummary` to true
             self = try .opaque(name: name, typeName: typeName, summary: summary, preferBriefSummary: false, representation: customOpaqueLoggable.opaqueRepresentation())
         }

PlaygroundLogger/PlaygroundLoggerTests/CustomPlaygroundDisplayConvertibleTests.swift

@@ -0,0 +1,48 @@
+//===--- CustomPlaygroundDisplayConvertibleTests.swift --------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2018 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import XCTest
+@testable import PlaygroundLogger
+
+import CoreGraphics
+
+class CustomPlaygroundDisplayConvertibleTests: XCTestCase {
+    func testBasicConformance() throws {
+        struct MyPoint: CustomPlaygroundDisplayConvertible {
+            let x: Int
+            let y: Int
+
+            var playgroundDescription: Any {
+                return CGPoint(x: x, y: y)
+            }
+        }
+
+        let point = MyPoint(x: 4, y: 3)
+
+        let logEntry = try LogEntry(describing: point, name: "point", policy: .default)
+
+        guard case let .opaque(name, typeName, _, _, representation) = logEntry else {
+            XCTFail("Expected an instance of MyPoint to generate an opaque log entry")
+            return
+        }
+
+        XCTAssertEqual(name, "point")
+        XCTAssert(typeName.hasSuffix(".MyPoint"))
+
+        guard let pointRepresentation = representation as? CGPoint else {
+            XCTFail("Expected an instance of MyPoint to generate a CGPoint as its opaque representation")
+            return
+        }
+
+        XCTAssertEqual(pointRepresentation, CGPoint(x: 4, y: 3))
+    }
+}