ModMetadataFiles: Only log a warning with broken mods.toml

src/main/java/dev/architectury/loom/metadata/ErroringModMetadataFile.java

@@ -0,0 +1,48 @@
+package dev.architectury.loom.metadata;
+
+import net.fabricmc.loom.configuration.ifaceinject.InterfaceInjectionProcessor;
+
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.VisibleForTesting;
+
+import java.util.List;
+import java.util.Set;
+
+/**
+ * A fallback mod metadata file that represents a non-fatal format error
+ * in another file type. An example of such file type is mods.toml,
+ * which doesn't necessarily need to be parsed – it primarily needs to just exist.
+ */
+@VisibleForTesting
+public final class ErroringModMetadataFile implements ModMetadataFile {
+	private final String fileName;
+
+	ErroringModMetadataFile(String fileName) {
+		this.fileName = fileName;
+	}
+
+	@Override
+	public Set<String> getIds() {
+		return Set.of();
+	}
+
+	@Override
+	public Set<String> getAccessWideners() {
+		return Set.of();
+	}
+
+	@Override
+	public List<InterfaceInjectionProcessor.InjectedInterface> getInjectedInterfaces(@Nullable String modId) {
+		return List.of();
+	}
+
+	@Override
+	public String getFileName() {
+		return fileName + " [erroring]";
+	}
+
+	@Override
+	public List<String> getMixinConfigs() {
+		return List.of();
+	}
+}

src/main/java/dev/architectury/loom/metadata/ModMetadataFiles.java

@@ -6,8 +6,11 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Map;
 import java.util.function.Function;
+import java.util.function.Supplier;
 
 import com.google.common.collect.ImmutableMap;
+import org.gradle.api.logging.Logger;
+import org.gradle.api.logging.Logging;
 import org.gradle.api.tasks.SourceSet;
 import org.jetbrains.annotations.Nullable;
 
@@ -18,12 +21,24 @@ import net.fabricmc.loom.util.gradle.SourceSetHelper;
  * Utilities for reading mod metadata files.
  */
 public final class ModMetadataFiles {
+	private static final Logger LOGGER = Logging.getLogger(ModMetadataFiles.class);
 	private static final Map<String, Function<byte[], ModMetadataFile>> SINGLE_FILE_METADATA_TYPES = ImmutableMap.<String, Function<byte[], ModMetadataFile>>builder()
 			.put(ArchitecturyCommonJson.FILE_NAME, ArchitecturyCommonJson::of)
 			.put(QuiltModJson.FILE_NAME, QuiltModJson::of)
-			.put(ModsToml.FILE_PATH, ModsToml::of)
+			.put(ModsToml.FILE_PATH, onError(ModsToml::of, "Could not load mods.toml", () -> new ErroringModMetadataFile("mods.toml")))
 			.build();
 
+	private static <A, B> Function<A, B> onError(Function<A, B> fn, String message, Supplier<B> onError) {
+		return a -> {
+			try {
+				return fn.apply(a);
+			} catch (Exception e) {
+				LOGGER.warn(message, e);
+				return onError.get();
+			}
+		};
+	}
+
 	/**
 	 * Reads the mod metadata file from a jar.
 	 *