From 2d8e6c806db00fd87b86f4b135db1d459850beb1 Mon Sep 17 00:00:00 2001
From: Camotoy <20743703+Camotoy@users.noreply.github.com>
Date: Sun, 26 May 2024 19:06:21 -0400
Subject: [PATCH] Friendly error if implementation name cannot be found

---
 .../interfaces/processor/ConfigImplementationGenerator.java   | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/extra/interface/ap/src/main/java/org/spongepowered/configurate/interfaces/processor/ConfigImplementationGenerator.java b/extra/interface/ap/src/main/java/org/spongepowered/configurate/interfaces/processor/ConfigImplementationGenerator.java
index e6c89dcd..b45cef94 100644
--- a/extra/interface/ap/src/main/java/org/spongepowered/configurate/interfaces/processor/ConfigImplementationGenerator.java
+++ b/extra/interface/ap/src/main/java/org/spongepowered/configurate/interfaces/processor/ConfigImplementationGenerator.java
@@ -188,6 +188,10 @@ private boolean gatherElementSpec(
                 if (nodeTypeElement.getKind().isInterface()) {
                     // first find the generated class for given type
                     String implName = this.processor.generatedClasses().getProperty(configClass.reflectionName());
+                    if (implName == null) {
+                        this.processor.printError("Could not determine an implementation type for method " + element.getSimpleName());
+                        return false;
+                    }
                     // make it canonical and replace superinterface type with source interface type if present
                     implName = implName.replace('$', '.').replace(type.getQualifiedName(), this.source.getQualifiedName());
                     configClass = ClassName.bestGuess(implName);