feat: introduce @system/Scope, allow inputs inside subgraphs

src/main/compiler/CompilerScope.ts

@@ -233,6 +233,8 @@ export class CompilerScope {
                 return this.emitParamNode(node, resSym);
             case '@system/Input':
                 return this.emitInputNode(node, resSym);
+            case '@system/Scope':
+                return this.emitScopeNode(node, resSym);
             case '@system/Result':
             case '@system/Output':
                 return this.emitOutputNode(node, resSym);
@@ -265,7 +267,13 @@ export class CompilerScope {
     }
 
     private emitInputNode(node: NodeView, resSym: string) {
-        this.code.line(`${resSym} = params;`);
+        this.code.line(`${resSym} = { ...params, ...ctx.getScopeData() };`);
+        // TODO phase out the workaround after subgraphs are migrated to Scope + Param nodes
+        // this.code.line(`${resSym} = params;`);
+    }
+
+    private emitScopeNode(node: NodeView, resSym: string) {
+        this.code.line(`${resSym} = ctx.getScopeData();`);
     }
 
     private emitOutputNode(node: NodeView, resSym: string) {
@@ -367,14 +375,14 @@ export class CompilerScope {
         const sym = this.symbols.getNodeSym(rootNode.nodeUid);
         if (this.options.introspect) {
             return [
-                `(params, ctx) => {`,
-                `ctx.scopeCaptured.emit({ nodeUid: ${JSON.stringify(node.nodeUid)}, params });`,
+                `(scopeData, ctx) => {`,
+                `ctx.scopeCaptured.emit({ nodeUid: ${JSON.stringify(node.nodeUid)}, params: scopeData });`,
                 `ctx.checkPendingNode(${JSON.stringify(node.nodeUid)});`,
-                `return ${sym}(params, ctx);`,
+                `return ${sym}(params, ctx.setScopeData(scopeData));`,
                 `}`,
             ].join('');
         }
-        return sym;
+        return `(scopeData, ctx) => ${sym}(params, ctx.setScopeData(scopeData))`;
     }
 
     private emitNodeProps(node: NodeView) {

src/main/runtime/GraphEvalContext.ts

@@ -25,6 +25,8 @@ export class GraphEvalContext implements t.GraphEvalContext {
     // Locals are stored per-context. Lookups delegate up the hierarchy.
     locals = new Map<string, any>();
 
+    scopeData: any = undefined;
+
     constructor(
         readonly parent: GraphEvalContext | null = null,
     ) {
@@ -68,6 +70,15 @@ export class GraphEvalContext implements t.GraphEvalContext {
         return new GraphEvalContext(this);
     }
 
+    getScopeData() {
+        return this.scopeData;
+    }
+
+    setScopeData(data: any) {
+        this.scopeData = data;
+        return this;
+    }
+
     convertType(value: unknown, schema: SchemaSpec) {
         return new Schema(schema as any).decode(value);
     }

src/main/runtime/ModuleLoader.ts

@@ -25,6 +25,7 @@ export abstract class GenericModuleLoader implements ModuleLoader {
         this.addModule('@system/Output', systemModules.Output);
         this.addModule('@system/Param', systemModules.Param);
         this.addModule('@system/Result', systemModules.Output);
+        this.addModule('@system/Scope', systemModules.Scope);
     }
 
     abstract resolveComputeUrl(ref: string): string;

src/main/system/Scope.ts

@@ -0,0 +1,17 @@
+import { ModuleSpecSchema } from '../schema/ModuleSpec.js';
+
+export const Scope = ModuleSpecSchema.create({
+    moduleName: 'Scope',
+    version: '0.0.0',
+    params: {
+    },
+    result: {
+        schema: { type: 'any' },
+    },
+    cacheMode: 'never',
+    attributes: {
+        hidden: true,
+        hideEvalControls: true,
+        forceColor: 'cyan',
+    }
+});

src/main/system/index.ts

@@ -9,3 +9,4 @@ export * from './Frame.js';
 export * from './Input.js';
 export * from './Output.js';
 export * from './Param.js';
+export * from './Scope.js';

src/main/types/ctx.ts

@@ -19,6 +19,8 @@ export interface GraphEvalContext {
     clear(): void;
     finalize(): Promise<void>;
     newScope(): GraphEvalContext;
+    getScopeData(): any;
+    setScopeData(data: any): this;
     checkPendingNode(nodeUid: string): void;
 
     getLocal<T>(key: string, defaultValue?: T): T | undefined;