When following a pointer, adjust targetDoc to point to the root of the current doc (commontoolsinc#1805)

* When following a pointer, adjust targetDoc to point to the root of the current doc, since our pointers may point outside of the portion where we are.

* Added unit test

* Removed unused test class

Author: ubik2

packages/runner/src/traverse.ts

@@ -468,10 +468,6 @@ function followPointer<S extends BaseMemoryAddress>(
   const target: BaseMemoryAddress = (link.id !== undefined)
     ? { id: link.id, type: "application/json" }
     : doc.address;
-  const targetDoc = {
-    address: doc.address,
-    value: doc.value,
-  };
   if (selector !== undefined) {
     // We'll need to re-root the selector for the target doc
     // Remove the portions of doc.path from selector.path, limiting schema if
@@ -492,43 +488,47 @@ function followPointer<S extends BaseMemoryAddress>(
     // Cycle detected - treat this as notFound to avoid traversal
     return [notFound(doc.address), selector];
   }
+  // We may access portions of the doc outside what we have in our doc
+  // attestation, so reload the top level doc from the manager.
+  const valueEntry = manager.load(target);
+  if (valueEntry === null) {
+    return [notFound(doc.address), selector];
+  }
   if (link.id !== undefined) {
-    // We have a reference to a different cell, so track the dependency
+    // We have a reference to a different doc, so track the dependency
     // and update our targetDoc
-    const valueEntry = manager.load(target);
-    if (valueEntry === null) {
-      return [notFound(doc.address), selector];
-    }
     if (schemaTracker !== undefined && selector !== undefined) {
       schemaTracker.add(manager.toKey(target), selector);
     }
-    // If the object we're pointing to is a retracted fact, just return undefined.
-    // We can't do a better match, but we do want to include the result so we watch this doc
-    if (valueEntry.value === undefined) {
-      return [notFound(target), selector];
+    // Load the sources/recipes recursively unless we're a retracted fact.
+    if (valueEntry.value !== undefined) {
+      loadSource(
+        manager,
+        valueEntry,
+        new Set<string>(),
+        schemaTracker,
+      );
     }
-    // Otherwise, we can continue with the target.
-    // an assertion fact.is will be an object with a value property, and
-    // that's what our schema is relative to.
-    targetDoc.address = { ...target, path: ["value"] };
-    targetDoc.value = (valueEntry.value as Immutable<JSONObject>)["value"];
-    // Load any sources (recursively) if they exist and any linked recipes
-    loadSource(
-      manager,
-      valueEntry,
-      new Set<string>(),
-      schemaTracker,
-    );
   }
+  // If the object we're pointing to is a retracted fact, just return undefined.
+  // We can't do a better match, but we do want to include the result so we watch this doc
+  if (valueEntry.value === undefined) {
+    return [notFound(target), selector];
+  }
+  // We can continue with the target, but provide the top level target doc
+  // to getAtPath.
+  // An assertion fact.is will be an object with a value property, and
+  // that's what our schema is relative to, so we'll grab the value part.
+  const targetDoc = {
+    address: { ...target, path: ["value"] },
+    value: (valueEntry.value as Immutable<JSONObject>)["value"],
+  };
 
   // We've loaded the linked doc, so walk the path to get to the right part of that doc (or whatever doc that path leads to),
   // then the provided path from the arguments.
   return getAtPath(
     manager,
-    {
-      address: targetDoc.address,
-      value: targetDoc.value,
-    },
+    targetDoc,
     [...link.path, ...path] as string[],
     tracker,
     schemaTracker,

packages/runner/test/traverse.test.ts

@@ -0,0 +1,105 @@
+import { describe, it } from "@std/testing/bdd";
+import { expect } from "@std/expect";
+import { refer } from "merkle-reference/json";
+import type {
+  Entity,
+  Revision,
+  State,
+  URI,
+} from "@commontools/memory/interface";
+import { SchemaObjectTraverser } from "../src/traverse.ts";
+import { StoreObjectManager } from "../src/storage/query.ts";
+
+describe("SchemaObjectTraverser.traverseDAG", () => {
+  it("follows legacy cell links when traversing", () => {
+    const store = new Map<string, Revision<State>>();
+    const type = "application/json" as const;
+    const doc1Uri = "of:doc-1" as URI;
+    const doc2Uri = "of:doc-2" as URI;
+    const doc1Entity = doc1Uri as Entity;
+    const doc2Entity = doc2Uri as Entity;
+
+    const doc1Value = { employees: [{ name: "Bob" }] };
+    const doc1EntityId = { "/": doc1Uri };
+
+    const doc1Revision: Revision<State> = {
+      the: type,
+      of: doc1Entity,
+      is: { value: doc1Value },
+      cause: refer({ the: type, of: doc1Entity }),
+      since: 1,
+    };
+    store.set(
+      `${doc1Revision.of}/${doc1Revision.the}`,
+      doc1Revision,
+    );
+
+    const doc2Value = {
+      employeeName: {
+        cell: doc1EntityId,
+        path: ["employees", "0", "name"],
+      },
+      argument: {
+        tools: {
+          search_web: {
+            pattern: {
+              result: {
+                $alias: {
+                  path: ["internal", "__#0"],
+                },
+              },
+            },
+          },
+        },
+      },
+      internal: {
+        "__#0": {
+          name: "Foo",
+        },
+      },
+    };
+
+    const doc2Revision: Revision<State> = {
+      the: type,
+      of: doc2Entity,
+      is: { value: doc2Value },
+      cause: refer({ the: type, of: doc2Entity }),
+      since: 2,
+    };
+    store.set(
+      `${doc2Revision.of}/${doc2Revision.the}`,
+      doc2Revision,
+    );
+
+    const manager = new StoreObjectManager(store);
+    const traverser = new SchemaObjectTraverser(manager, {
+      path: [],
+      schemaContext: { schema: true, rootSchema: true },
+    });
+
+    const result = traverser.traverse({
+      address: { id: doc2Uri, type, path: ["value"] },
+      value: doc2Value,
+    });
+
+    expect(result).toEqual({
+      argument: {
+        tools: {
+          search_web: {
+            pattern: {
+              result: {
+                name: "Foo",
+              },
+            },
+          },
+        },
+      },
+      employeeName: "Bob",
+      internal: {
+        "__#0": {
+          name: "Foo",
+        },
+      },
+    });
+  });
+});