From 4adf8611131a5d86b15f017a42a0366837d14528 Mon Sep 17 00:00:00 2001
From: Jesse Plamondon-Willard <Pathoschild@users.noreply.github.com>
Date: Wed, 13 Apr 2022 21:07:43 -0400
Subject: enable nullable annotations in the rest of SMAPI core (#837)

---
 src/SMAPI/Utilities/KeybindList.cs |  2 +-
 src/SMAPI/Utilities/PerScreen.cs   | 23 ++++++++++++++++++-----
 2 files changed, 19 insertions(+), 6 deletions(-)

(limited to 'src/SMAPI/Utilities')

diff --git a/src/SMAPI/Utilities/KeybindList.cs b/src/SMAPI/Utilities/KeybindList.cs
index 18eeb9fd..aa12a37a 100644
--- a/src/SMAPI/Utilities/KeybindList.cs
+++ b/src/SMAPI/Utilities/KeybindList.cs
@@ -50,7 +50,7 @@ namespace StardewModdingAPI.Utilities
         /// <param name="input">The keybind string. See remarks on <see cref="ToString"/> for format details.</param>
         /// <param name="parsed">The parsed keybind list, if valid.</param>
         /// <param name="errors">The errors that occurred while parsing the input, if any.</param>
-        public static bool TryParse(string input, [NotNullWhen(true)] out KeybindList? parsed, out string[] errors)
+        public static bool TryParse(string? input, [NotNullWhen(true)] out KeybindList? parsed, out string[] errors)
         {
             // empty input
             if (string.IsNullOrWhiteSpace(input))
diff --git a/src/SMAPI/Utilities/PerScreen.cs b/src/SMAPI/Utilities/PerScreen.cs
index afe3ba91..799ff63b 100644
--- a/src/SMAPI/Utilities/PerScreen.cs
+++ b/src/SMAPI/Utilities/PerScreen.cs
@@ -1,8 +1,7 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using StardewModdingAPI.Framework;
 
 namespace StardewModdingAPI.Utilities
 {
@@ -39,14 +38,28 @@ namespace StardewModdingAPI.Utilities
         ** Public methods
         *********/
         /// <summary>Construct an instance.</summary>
+        /// <remarks><strong>Limitation with nullable reference types:</strong> when the underlying type <typeparamref name="T"/> is nullable, this sets the default value to null regardless of whether you marked the type parameter nullable. To avoid that, set the default value with the 'createNewState' argument instead.</remarks>
         public PerScreen()
-            : this(null) { }
+            : this(null!) { }
 
         /// <summary>Construct an instance.</summary>
         /// <param name="createNewState">Create the initial state for a screen.</param>
         public PerScreen(Func<T> createNewState)
         {
-            this.CreateNewState = createNewState ?? (() => default);
+            // ReSharper disable once ConditionIsAlwaysTrueOrFalse -- required for backwards compatibility
+            if (createNewState is null)
+            {
+                SCore.DeprecationManager.Warn(
+                    SCore.DeprecationManager.GetSourceNameFromStack(),
+                    $"calling the {nameof(PerScreen<T>)} constructor with null",
+                    "3.14.0",
+                    DeprecationLevel.Notice
+                );
+
+                createNewState = (() => default!);
+            }
+
+            this.CreateNewState = createNewState;
         }
 
         /// <summary>Get all active values by screen ID. This doesn't initialize the value for a screen ID if it's not created yet.</summary>
@@ -61,7 +74,7 @@ namespace StardewModdingAPI.Utilities
         public T GetValueForScreen(int screenId)
         {
             this.RemoveDeadScreens();
-            return this.States.TryGetValue(screenId, out T state)
+            return this.States.TryGetValue(screenId, out T? state)
                 ? state
                 : this.States[screenId] = this.CreateNewState();
         }
-- 
cgit