[feat]: add swift-log dep & some more logging

Author: jamieQ

Package.swift

@@ -62,13 +62,17 @@ let package = Package(
         .package(url: "https://github.com/pointfreeco/swift-perception", "1.5.0" ..< "3.0.0"),
         .package(url: "https://github.com/pointfreeco/swift-custom-dump", from: "1.3.3"),
         .package(url: "https://github.com/pointfreeco/xctest-dynamic-overlay", from: "1.0.0"),
+        .package(url: "https://github.com/apple/swift-log.git", from: "1.0.0"),
     ],
     targets: [
         // MARK: Workflow
 
         .target(
             name: "Workflow",
-            dependencies: ["ReactiveSwift"],
+            dependencies: [
+                .product(name: "Logging", package: "swift-log"),
+                "ReactiveSwift",
+            ],
             path: "Workflow/Sources"
         ),
         .target(

Samples/Tuist/Package.resolved

@@ -153,7 +153,10 @@ public class RenderContext<WorkflowType: Workflow>: RenderContextType {
         }
 
         private func assertStillValid() {
-            assert(isValid, "A `RenderContext` instance was used outside of the workflow's `render` method. It is a programmer error to capture a context in a closure or otherwise cause it to be used outside of the `render` method.")
+            if !isValid {
+                WorkflowLogger.logExternal(as: .error, "A `RenderContext` instance was used outside of the workflow's `render` method. It is a programmer error to capture a context in a closure or otherwise cause it to be used outside of the `render` method.")
+                assertionFailure("A `RenderContext` instance was used outside of the workflow's `render` method. It is a programmer error to capture a context in a closure or otherwise cause it to be used outside of the `render` method.")
+            }
         }
     }
 }

Workflow/Sources/RenderContext.swift

@@ -409,27 +409,25 @@ extension WorkflowNode.SubtreeManager {
             case .valid(let handler):
                 handler(event)
 
-            case .invalid:
-                #if DEBUG
+            #if DEBUG
+            case .invalid where isReentrantCall:
                 // Reentrancy seems to often be due to UIKit behaviors over
                 // which we have little control (e.g. synchronous resignation
                 // of first responder after a new Rendering is assigned). Emit
                 // some debug info in these cases.
-                if isReentrantCall {
-                    print("[\(WorkflowType.self)]: ℹ️ Sink sent another action after it was invalidated but before its original action handling was resolved. This new action will be ignored. If this is unexpected, set a Swift error breakpoint on `\(InvalidSinkSentAction.self)` to debug.")
-                }
+                WorkflowLogger.logExternal(as: .info, "[\(WorkflowType.self)]: ℹ️ Sink sent another action after it was invalidated but before its original action handling was resolved. This new action will be ignored. If this is unexpected, set a Swift error breakpoint on `\(InvalidSinkSentAction.self)` to debug.")
+                do { throw InvalidSinkSentAction() } catch {}
+            #endif
 
-                do {
-                    throw InvalidSinkSentAction()
-                } catch {}
-                #endif
-
-                // If we're invalid and this is the first time `handle()` has
-                // been called, then it's likely we've somehow been inadvertently
-                // retained from the 'outside world'. Fail more loudly in this case.
-                assert(isReentrantCall, """
-                    [\(WorkflowType.self)]: Sink sent an action after it was invalidated. This action will be ignored.
-                """)
+            case .invalid where !isReentrantCall:
+                // If we've already been invalidated when `handle()` is initially
+                // called, then it's likely we've somehow been inadvertently retained
+                // from the 'outside world'. Fail more loudly in this case.
+                WorkflowLogger.logExternal(as: .warning, "[\(WorkflowType.self)]: Sink sent an action after it was invalidated. This action will be ignored.")
+                assertionFailure("[\(WorkflowType.self)]: Sink sent an action after it was invalidated. This action will be ignored.")
+
+            case .invalid:
+                break
             }
         }
 

Workflow/Sources/SubtreeManager.swift

@@ -15,6 +15,7 @@
  */
 
 import Foundation
+import Logging
 import os.signpost
 
 extension OSLog {
@@ -207,3 +208,33 @@ enum WorkflowLogger {
         }
     }
 }
+
+// MARK: - External Logging
+
+typealias ExternalLogger = Logging.Logger
+
+extension WorkflowLogger {
+    static func logExternal(
+        as level: ExternalLogger.Level,
+        _ message: @autoclosure () -> ExternalLogger.Message,
+        metadata: @autoclosure () -> ExternalLogger.Metadata? = nil,
+        source: @autoclosure () -> String? = nil,
+        file: String = #fileID,
+        function: String = #function,
+        line: UInt = #line
+    ) {
+        ExternalLogger.workflow.log(
+            level: level,
+            message(),
+            metadata: metadata(),
+            source: source(),
+            file: file,
+            function: function,
+            line: line
+        )
+    }
+}
+
+extension ExternalLogger {
+    static let workflow = Logger(label: "com.squareup.workflow")
+}