fix dev run, only run datagen if files changed

.gitignore

@@ -21,4 +21,4 @@ bin/
 run/
 logs/
 
-src/generated/
+src/generated/output/

build.gradle.kts

@@ -51,12 +51,16 @@ sourceSets {
     }
 
     val generated by creating {
+        compiledBy("runDatagen")
         resources {
-            compiledBy("runDatagen")
+            srcDir(file("src/generated/output"))
         }
     }
 
-    main.runtimeClasspath += generated.output
+    devrun.apply {
+        compileClasspath += generated.output
+        runtimeClasspath += generated.output
+    }
 }
 
 loom {
@@ -74,7 +78,7 @@ loom {
             name("Data Generation")
             vmArgs(
                 "-Dfabric-api.datagen",
-                "-Dfabric-api.datagen.output-dir=${file("src/generated/resources")}",
+                "-Dfabric-api.datagen.output-dir=${file("src/generated/output")}",
                 "-Dfabric-api.datagen.modid=slotlink_datagen"
             )
             runDir("${project.buildDir}/datagen")
@@ -88,6 +92,11 @@ java {
     targetCompatibility = JavaVersion.VERSION_17
 }
 
+tasks.getByName("runDatagen") {
+    inputs.dir(file("src/datagen"))
+    outputs.dir(file("src/generated"))
+}
+
 tasks.withType<JavaCompile> {
     options.encoding = "UTF-8"
 }
@@ -100,10 +109,15 @@ tasks.withType<KotlinCompile> {
 
 tasks.jar {
     from(sourceSets["generated"].output) {
+        exclude("fabric.mod.json")
         exclude(".cache/**")
     }
 }
 
+tasks.getByName("processGeneratedResources") {
+    dependsOn("runDatagen")
+}
+
 tasks.withType<ProcessResources> {
     inputs.property("version", project.version)
 

src/generated/resources/fabric.mod.json

@@ -0,0 +1,5 @@
+{
+  "schemaVersion": 1,
+  "id"           : "slotlink_generated_data",
+  "version"      : "1"
+}