Remove hard-coding of several assumptions about the NeoForm config

src/main/java/net/neoforged/neoform/runtime/actions/PatchActionFactory.java

@@ -5,6 +5,7 @@
 import net.neoforged.neoform.runtime.graph.NodeOutput;
 import net.neoforged.neoform.runtime.graph.NodeOutputType;
 import net.neoforged.neoform.runtime.utils.ToolCoordinate;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
 import java.util.Objects;
@@ -13,11 +14,15 @@ public final class PatchActionFactory {
 
     public static NodeOutput makeAction(ExecutionNodeBuilder builder,
                                         DataSource patches,
-                                        NodeOutput sources,
+                                        @Nullable NodeOutput sources,
                                         String basePathPrefix,
                                         String modifiedPathPrefix) {
         Objects.requireNonNull(patches, "patches");
-        builder.input("input", sources.asInput());
+        if (sources != null) {
+            builder.input("input", sources.asInput());
+        } else if (!builder.hasInput("input")) {
+            throw new IllegalStateException("The builder must have an input named 'input' when no explit sources are given.");
+        }
         var mainOutput = builder.output("output", NodeOutputType.ZIP, "ZIP file containing the patched sources");
         builder.output("outputRejects", NodeOutputType.ZIP, "ZIP file containing the rejected patches");
 

src/main/java/net/neoforged/neoform/runtime/actions/SplitResourcesFromClassesAction.java

@@ -67,7 +67,7 @@ public void run(ProcessingEnvironment environment) throws IOException, Interrupt
         Path mappingsPath = null;
         if (generateDistManifestSettings != null) {
             otherDistJarPath = environment.getRequiredInputPath(INPUT_OTHER_DIST_JAR);
-            mappingsPath = environment.getRequiredInputPath(INPUT_MAPPINGS);
+            mappingsPath = environment.getInputPath(INPUT_MAPPINGS);
         }
 
         var classesJar = environment.getOutputPath("output");
@@ -132,6 +132,7 @@ private static void generateDistSourceManifest(String distId,
                                                    ZipFile jar,
                                                    String otherDistId,
                                                    Path otherDistJarPath,
+                                                   @Nullable
                                                    Path mappingsPath,
                                                    JarOutputStream resourcesJarOut) throws IOException {
         var mappings = mappingsPath != null ? IMappingFile.load(mappingsPath.toFile()) : null;

src/main/java/net/neoforged/neoform/runtime/cli/RunNeoFormCommand.java

@@ -348,7 +348,7 @@ private void execute(NeoFormEngine engine) throws InterruptedException, IOExcept
                 ));
 
         if (neededResults.isEmpty()) {
-            System.err.println("No results requested. Available results: " + engine.getAvailableResults());
+            System.err.println("No results requested using --write-result=<result>:<path>. Available results: " + engine.getAvailableResults());
             System.exit(1);
         }
 

src/main/java/net/neoforged/neoform/runtime/engine/NeoFormEngine.java

@@ -28,6 +28,7 @@
 import net.neoforged.neoform.runtime.graph.ExecutionNode;
 import net.neoforged.neoform.runtime.graph.ExecutionNodeBuilder;
 import net.neoforged.neoform.runtime.graph.NodeExecutionException;
+import net.neoforged.neoform.runtime.graph.NodeInput;
 import net.neoforged.neoform.runtime.graph.NodeOutput;
 import net.neoforged.neoform.runtime.graph.NodeOutputType;
 import net.neoforged.neoform.runtime.graph.ResultRepresentation;
@@ -39,6 +40,7 @@
 import net.neoforged.neoform.runtime.utils.OsUtil;
 import net.neoforged.neoform.runtime.utils.StringUtil;
 import net.neoforged.problems.ProblemReporter;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.IOException;
 import java.io.PrintWriter;
@@ -182,16 +184,18 @@ public void loadNeoFormProcess(NeoFormDistConfig distConfig) {
             addNodeForStep(graph, distConfig, step);
         }
 
-        var renameOutput = graph.getRequiredOutput("rename", "output");
-
         var sourcesOutput = graph.getRequiredOutput("patch", "output");
 
         var compiledOutput = addRecompileStep(distConfig, sourcesOutput);
 
         var sourcesAndCompiledOutput = addMergeWithSourcesStep(compiledOutput, sourcesOutput);
 
         // Register the sources and the compiled binary as results
-        graph.setResult("vanillaDeobfuscated", renameOutput);
+        // Vanilla deobfuscated is equivalent to the input to the decompiler
+        var decompile = graph.getNode("decompile");
+        if (decompile != null && decompile.inputs().get("input") instanceof NodeInput.NodeInputForOutput nodeInputForOutput) {
+            graph.setResult("vanillaDeobfuscated", nodeInputForOutput.getOutput());
+        }
         graph.setResult("sources", sourcesOutput);
         graph.setResult("compiled", compiledOutput);
         graph.setResult("sourcesAndCompiled", sourcesAndCompiledOutput);
@@ -343,11 +347,15 @@ private void addNodeForStep(ExecutionGraph graph, NeoFormDistConfig config, NeoF
 
                         action.generateSplitManifest("client", "server");
                         builder.input(SplitResourcesFromClassesAction.INPUT_OTHER_DIST_JAR, serverJarInput);
-                        builder.input(SplitResourcesFromClassesAction.INPUT_MAPPINGS, graph.getRequiredOutput("mergeMappings", "output").asInput());
+                        if (graph.hasOutput("mergeMappings", "output")) {
+                            builder.input(SplitResourcesFromClassesAction.INPUT_MAPPINGS, graph.getRequiredOutput("mergeMappings", "output").asInput());
+                        }
                     } else if ("stripServer".equals(step.getId())) {
                         action.generateSplitManifest("server", "client");
                         builder.input(SplitResourcesFromClassesAction.INPUT_OTHER_DIST_JAR, graph.getRequiredOutput("downloadClient", "output").asInput());
-                        builder.input(SplitResourcesFromClassesAction.INPUT_MAPPINGS, graph.getRequiredOutput("mergeMappings", "output").asInput());
+                        if (graph.hasOutput("mergeMappings", "output")) {
+                            builder.input(SplitResourcesFromClassesAction.INPUT_MAPPINGS, graph.getRequiredOutput("mergeMappings", "output").asInput());
+                        }
                     }
                 }
 
@@ -363,11 +371,10 @@ private void addNodeForStep(ExecutionGraph graph, NeoFormDistConfig config, NeoF
                 ));
             }
             case "patch" -> {
-                builder.clearInputs();
                 PatchActionFactory.makeAction(
                         builder,
                         getRequiredDataSource("patches"),
-                        graph.getRequiredOutput("inject", "output"),
+                        null,
                         "a/",
                         "b/"
                 );
@@ -790,6 +797,12 @@ public <T> T getRequiredInput(String id, ResultRepresentation<T> representation)
             return node.getRequiredInput(id).getValue(representation);
         }
 
+        @Nullable
+        @Override
+        public <T> T getInput(String id, ResultRepresentation<T> representation) throws IOException {
+            return node.hasInput(id) ? node.getRequiredInput(id).getValue(representation) : null;
+        }
+
         @Override
         public Path getOutputPath(String id) {
             var output = node.getRequiredOutput(id);

src/main/java/net/neoforged/neoform/runtime/engine/ProcessingEnvironment.java

@@ -3,6 +3,7 @@
 import net.neoforged.neoform.runtime.artifacts.ArtifactManager;
 import net.neoforged.neoform.runtime.graph.ResultRepresentation;
 import net.neoforged.problems.ProblemReporter;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
@@ -43,8 +44,20 @@ default Path getRequiredInputPath(String id) {
         }
     }
 
+    @Nullable
+    default Path getInputPath(String id) {
+        try {
+            return getInput(id, ResultRepresentation.PATH);
+        } catch (IOException e) {
+            throw new UncheckedIOException(e); // Getting a path should not fail
+        }
+    }
+
     <T> T getRequiredInput(String id, ResultRepresentation<T> representation) throws IOException;
 
+    @Nullable
+    <T> T getInput(String id, ResultRepresentation<T> representation) throws IOException;
+
     /**
      * Also automatically calls {@link #setOutput(String, Path)} with the generated path.
      */

src/main/java/net/neoforged/neoform/runtime/graph/ExecutionNode.java

@@ -125,6 +125,10 @@ public Map<String, NodeInput> inputs() {
         return inputs;
     }
 
+    public boolean hasInput(String id) {
+        return inputs.containsKey(id);
+    }
+
     public boolean hasOutput(String id) {
         return outputs.containsKey(id);
     }

src/main/java/net/neoforged/neoform/runtime/graph/NodeInput.java

@@ -37,13 +37,17 @@ void setNode(ExecutionNode node) {
 
     public abstract <T> T getValue(ResultRepresentation<T> representation) throws IOException;
 
-    static final class NodeInputForOutput extends NodeInput {
+    public static final class NodeInputForOutput extends NodeInput {
         private NodeOutput output;
 
         public NodeInputForOutput(NodeOutput output) {
             this.output = output;
         }
 
+        public NodeOutput getOutput() {
+            return output;
+        }
+
         @Override
         public void replaceReferences(NodeOutput oldOutput, NodeOutput newOutput) {
             if (this.output == oldOutput) {