Update DisplayListPrinter to add Color and Effect support (#574)

Author: Kyle-Ye

Sources/OpenSwiftUICore/Render/DisplayList/DisplayListPrinter.swift

@@ -32,10 +32,20 @@ extension DisplayList.Item {
             switch content.value {
             case let .placeholder(id: identity):
                 printer.print("(placeholder \(identity))")
+            case let .color(resolved):
+                // FIXME
+                printer.print("(color \(resolved))")
             default:
                 // TOOD
                 break
             }
+        case let .effect(effect, displayList):
+            // FIXME
+            printer.push("effect")
+            for item in displayList.items {
+                item.print(into: &printer)
+            }
+            printer.pop()
         default:
             // TODO
             break
@@ -52,10 +62,20 @@ extension DisplayList.Item {
             switch content.value {
             case let .placeholder(id: identity):
                 printer.print("@\(identity))")
+            case let .color(resolved):
+                // FIXME
+                printer.print("(c \(resolved))")
             default:
                 // TOOD
                 break
             }
+        case let .effect(effect, displayList):
+            // FIXME
+            printer.push("E")
+            for item in displayList.items {
+                item.printMinimally(into: &printer)
+            }
+            printer.pop()
         default:
             // TODO
             break

Tests/OpenSwiftUICoreTests/Render/DisplayList/DisplayList+StringTests.swift

@@ -0,0 +1,136 @@
+//
+//  DisplayListPrinterTests.swift
+//  OpenSwiftUICoreTests
+
+import OpenSwiftUICore
+import Testing
+
+struct DisplayListPrinterTests {
+    @Test
+    func plain() {
+        let emptyList = DisplayList()
+        #expect(emptyList.description == "(display-list)")
+        #expect(emptyList.minimalDescription == "(DL)")
+    }
+    
+    @Test
+    func emptyItem() {
+        let item = DisplayList.Item(
+            .empty,
+            frame: .zero,
+            identity: .init(decodedValue: 1),
+            version: .init(decodedValue: 0)
+        )
+        let d = item.description
+        print(d)
+        
+        #expect(item.description == """
+        (display-list-item
+          (item #:identity 1 #:version 0
+            (frame (0.0 0.0; 0.0 0.0))))
+        """)
+        
+        let list = DisplayList(item)
+        #expect(list.description == "(display-list)")
+        #expect(list.minimalDescription == "(DL)")
+        
+        let list2 = DisplayList([item])
+        #expect(list2.description == """
+        (display-list
+          (item #:identity 1 #:version 0
+            (frame (0.0 0.0; 0.0 0.0))))
+        """)
+        #expect(list2.minimalDescription == "(DL(I:1))")
+    }
+    
+    func placeholderItem() {
+        let item = DisplayList.Item(
+            .content(.init(
+                .placeholder(id: .init(decodedValue: 2)),
+                seed: .init(decodedValue: 4)
+            )),
+            frame: .zero,
+            identity: .init(decodedValue: 1),
+            version: .init(decodedValue: 0)
+        )
+        let expectedDescription = """
+        (display-list
+          (item #:identity 1 #:version 0 #:views true
+            (frame (0.0 0.0; 0.0 0.0))
+            (content-seed 4)
+            (placeholder #2)))
+        """
+        
+        let expectedMinimalDescription = """
+        (DL(I:1 @#2))
+        """
+        
+        
+        let list = DisplayList(item)
+        #expect(list.description == expectedDescription)
+        #expect(list.minimalDescription == expectedMinimalDescription)
+        
+        let list2 = DisplayList([item])
+        #expect(list2.description == expectedDescription)
+        #expect(list2.minimalDescription == expectedMinimalDescription)
+    }
+
+    @Test
+    func colorItem() {
+        let item = DisplayList.Item(
+            .content(.init(
+                .color(.white),
+                seed: .init(decodedValue: 2))
+            ),
+            frame: .zero,
+            identity: .init(decodedValue: 1),
+            version: .init(decodedValue: 0)
+        )
+        #expect(DisplayList(item).description == """
+        (display-list
+          (item #:identity 1 #:version 0
+            (frame (0.0 0.0; 0.0 0.0))
+            (content-seed 2)
+            (color #FFFFFFFF)))
+        """)
+        #expect(DisplayList(item).minimalDescription == """
+        (DL(I:1 (c #FFFFFFFF)))
+        """)
+    }
+
+    @Test
+    func effectItem() {
+        let colorItem = DisplayList.Item(
+            .content(.init(
+                .color(.white),
+                seed: .init(decodedValue: 2))
+            ),
+            frame: .zero,
+            identity: .init(decodedValue: 1),
+            version: .init(decodedValue: 0)
+        )
+        let effectItem = DisplayList.Item(
+            .effect(
+                .opacity(1),
+                .init(colorItem)
+            ),
+            frame: .zero,
+            identity: .init(decodedValue: 4),
+            version: .init(decodedValue: 3)
+        )
+        // FIXME: opacity value should be printed since it is not canonicalized here
+        #expect(DisplayList(effectItem).description == """
+        (display-list
+          (item #:identity 4 #:version 3
+            (frame (0.0 0.0; 0.0 0.0))
+            (effect
+              (item #:identity 1 #:version 0
+                (frame (0.0 0.0; 0.0 0.0))
+                (content-seed 2)
+                (color #FFFFFFFF)))))
+        """)
+        #expect(DisplayList(effectItem).minimalDescription == """
+        (DL(I:4(E(I:1 (c #FFFFFFFF)))))
+        """)
+    }
+}

Tests/OpenSwiftUICoreTests/Render/DisplayList/DisplayListPrinterTests.swift

@@ -35,30 +35,21 @@ struct IDViewTests {
         graph.setRootView(ContentView())
         graph.setProposedSize(CGSize(width: 100, height: 100))
         let (displayList, _) = graph.displayList()
-
         let expectRegex = try! Regex(#"""
         \(display-list
           \(item #:identity \d+ #:version \d+
-            \(frame \([^)]+\)\)\)\)
-        """#)
-        #expect(displayList.description.contains(expectRegex))
-        withKnownIssue("Blocked by DisplayList.print and canonicalize") {
-            let expectRegex = try! Regex(#"""
-            \(display-list
+            \(frame \([^)]+\)\)
+            \(effect
               \(item #:identity \d+ #:version \d+
                 \(frame \([^)]+\)\)
-                \(effect
-                  \(item #:identity \d+ #:version \d+
-                    \(frame \([^)]+\)\)
-                    \(content-seed \d+\)
-                    \(color #[0-9A-F]{8}\)\)
-                  \(item #:identity \d+ #:version \d+
-                    \(frame \([^)]+\)\)
-                    \(content-seed \d+\)
-                    \(color #[0-9A-F]{8}\)\)\)\)\)
-            """#)
-            #expect(displayList.description.contains(expectRegex))
-        }
+                \(content-seed \d+\)
+                \(color #[0-9A-F]{8}\)\)
+              \(item #:identity \d+ #:version \d+
+                \(frame \([^)]+\)\)
+                \(content-seed \d+\)
+                \(color #[0-9A-F]{8}\)\)\)\)\)
+        """#)
+        #expect(displayList.description.contains(expectRegex))
     }
     #endif
 }