From 25b8a65c5c958428dc7d56d6b846399c9b429c00 Mon Sep 17 00:00:00 2001
From: Jonathan Coates <git@squiddev.cc>
Date: Fri, 21 Jun 2024 07:54:18 +0100
Subject: [PATCH] Fix drive.getAudioTitle returning null for no disk

Historically (and according to the docs) getAudioTitle returned "false"
when the drive was empty (or had invalid media), and "null" when the
disk had no item. This was accidentally changed in a later refactor --
this change fixes that behaviour.
---
 .../diskdrive/DiskDrivePeripheral.java        |  3 +-
 .../computercraft/gametest/Disk_Drive_Test.kt | 12 ++++++
 ...isk_drive_test.audio_title_when_empty.snbt | 40 +++++++++++++++++++
 3 files changed, 54 insertions(+), 1 deletion(-)
 create mode 100644 projects/common/src/testMod/resources/data/cctest/structures/disk_drive_test.audio_title_when_empty.snbt

diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDrivePeripheral.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDrivePeripheral.java
index 31cb03b20..d103baf96 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDrivePeripheral.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDrivePeripheral.java
@@ -129,7 +129,8 @@ public class DiskDrivePeripheral implements IPeripheral {
     @LuaFunction
     @Nullable
     public final Object getAudioTitle() {
-        return diskDrive.getMedia().getAudioTitle();
+        var stack = diskDrive.getMedia();
+        return stack.media() != null ? stack.getAudioTitle() : false;
     }
 
     /**
diff --git a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Disk_Drive_Test.kt b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Disk_Drive_Test.kt
index 11fd18344..245d56130 100644
--- a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Disk_Drive_Test.kt
+++ b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Disk_Drive_Test.kt
@@ -10,6 +10,7 @@ import dan200.computercraft.gametest.api.*
 import dan200.computercraft.shared.ModRegistry
 import dan200.computercraft.shared.media.items.DiskItem
 import dan200.computercraft.shared.peripheral.diskdrive.DiskDriveBlock
+import dan200.computercraft.shared.peripheral.diskdrive.DiskDrivePeripheral
 import dan200.computercraft.shared.peripheral.diskdrive.DiskDriveState
 import dan200.computercraft.test.core.assertArrayEquals
 import dan200.computercraft.test.core.computer.getApi
@@ -42,6 +43,17 @@ class Disk_Drive_Test {
         }
     }
 
+    /**
+     * [DiskDrivePeripheral] returns `false` when the item is not a disk (or is absent).
+     */
+    @GameTest
+    fun Audio_title_when_empty(helper: GameTestHelper) = helper.sequence {
+        thenOnComputer {
+            callPeripheral("right", "getAudioTitle")
+                .assertArrayEquals(false, message = "Correct audio title")
+        }
+    }
+
     @GameTest
     fun Ejects_disk(helper: GameTestHelper) = helper.sequence {
         val stackAt = BlockPos(2, 2, 2)
diff --git a/projects/common/src/testMod/resources/data/cctest/structures/disk_drive_test.audio_title_when_empty.snbt b/projects/common/src/testMod/resources/data/cctest/structures/disk_drive_test.audio_title_when_empty.snbt
new file mode 100644
index 000000000..9583c510b
--- /dev/null
+++ b/projects/common/src/testMod/resources/data/cctest/structures/disk_drive_test.audio_title_when_empty.snbt
@@ -0,0 +1,40 @@
+{
+    DataVersion: 2730,
+    size: [3, 3, 3],
+    data: [
+        {pos: [0, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [0, 1, 0], state: "minecraft:air"},
+        {pos: [0, 1, 1], state: "computercraft:disk_drive{facing:north,state:full}", nbt: {id: "computercraft:disk_drive"}},
+        {pos: [0, 1, 2], state: "minecraft:air"},
+        {pos: [1, 1, 0], state: "minecraft:air"},
+        {pos: [1, 1, 1], state: "computercraft:computer_advanced{facing:north,state:blinking}", nbt: {ComputerId: 1, Label: "disk_drive_test.audio_title_when_empty", On: 1b, id: "computercraft:computer_advanced"}},
+        {pos: [1, 1, 2], state: "minecraft:air"},
+        {pos: [2, 1, 0], state: "minecraft:air"},
+        {pos: [2, 1, 1], state: "minecraft:air"},
+        {pos: [2, 1, 2], state: "minecraft:air"},
+        {pos: [0, 2, 0], state: "minecraft:air"},
+        {pos: [0, 2, 1], state: "minecraft:air"},
+        {pos: [0, 2, 2], state: "minecraft:air"},
+        {pos: [1, 2, 0], state: "minecraft:air"},
+        {pos: [1, 2, 1], state: "minecraft:air"},
+        {pos: [1, 2, 2], state: "minecraft:air"},
+        {pos: [2, 2, 0], state: "minecraft:air"},
+        {pos: [2, 2, 1], state: "minecraft:air"},
+        {pos: [2, 2, 2], state: "minecraft:air"}
+    ],
+    entities: [],
+    palette: [
+        "minecraft:polished_andesite",
+        "minecraft:air",
+        "computercraft:disk_drive{facing:north,state:full}",
+        "computercraft:computer_advanced{facing:north,state:blinking}"
+    ]
+}