json schema small fix

Author: nx10

packages/core/src/backend/schema/jsonschema.test.ts

@@ -220,6 +220,36 @@ describe("JsonSchema generation", () => {
     expect(props["input1"]?.type).toBe("array");
     expect(props["input1"]?.items).toEqual({ type: "string" });
   });
+  it("handles subcommand with flag wrapping", () => {
+    const schema = schemaFor(
+      minimalDescriptor({
+        "command-line": "test [MASKS]",
+        inputs: [
+          {
+            id: "masks",
+            name: "Masks",
+            "value-key": "[MASKS]",
+            "command-line-flag": "--masks",
+            type: {
+              id: "masks",
+              "command-line": "[FIXED] [MOVING]",
+              inputs: [
+                { id: "fixed", "value-key": "[FIXED]", type: "String", optional: true },
+                { id: "moving", "value-key": "[MOVING]", type: "String", optional: false },
+              ],
+            },
+            optional: true,
+          },
+        ],
+      }),
+    );
+    const props = schema.properties as Record<string, JsonSchema>;
+    const masks = props["masks"];
+    expect(masks).toBeDefined();
+    const masksProps = masks?.properties as Record<string, JsonSchema>;
+    expect(masksProps["fixed"]?.type).toBe("string");
+    expect(masksProps["moving"]?.type).toBe("string");
+  });
 });
 
 describe("JsonSchemaBackend", () => {

packages/core/src/backend/schema/jsonschema.ts

@@ -82,6 +82,25 @@ class SchemaBuilder {
     }
   }
 
+  /** Find the sequence node whose child bindings match the struct's field names. */
+  private findStructNode(
+    node: Expr,
+    type: Extract<BoundType, { kind: "struct" }>,
+  ): Extract<Expr, { kind: "sequence" }> | undefined {
+    if (node.kind !== "sequence") return undefined;
+    // Check if any child binding matches a field name
+    for (const child of node.attrs.nodes) {
+      const binding = this.ctx.resolve(child);
+      if (binding && binding.name in type.fields) return node;
+    }
+    // Recurse into child sequences (handles collapsed flag sequences)
+    for (const child of node.attrs.nodes) {
+      const result = this.findStructNode(child, type);
+      if (result) return result;
+    }
+    return undefined;
+  }
+
   private findTerminal(node: Expr): Expr {
     switch (node.kind) {
       case "optional":
@@ -122,8 +141,9 @@ class SchemaBuilder {
     const properties: Record<string, JsonSchema> = {};
     const required: string[] = [];
 
-    if (node?.kind === "sequence") {
-      for (const child of node.attrs.nodes) {
+    const structNode = node ? this.findStructNode(node, type) : undefined;
+    if (structNode) {
+      for (const child of structNode.attrs.nodes) {
         const childBinding = this.ctx.resolve(child);
         if (childBinding && childBinding.name in type.fields) {
           properties[childBinding.name] = this.fromBinding(childBinding);