From b88762bd173b500d13ffa7d31f2d1b8097f07f57 Mon Sep 17 00:00:00 2001
From: Chris Swenson <cswenson@meta.com>
Date: Mon, 13 Jan 2025 17:15:24 -0600
Subject: [PATCH] Fix issue with referencing field in doubly-nested join inside
 a nest (#2092)

---
 .../malloy/src/lang/ast/field-space/query-spaces.ts |  6 ++++--
 packages/malloy/src/lang/test/query.spec.ts         | 13 +++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/packages/malloy/src/lang/ast/field-space/query-spaces.ts b/packages/malloy/src/lang/ast/field-space/query-spaces.ts
index 0c9f5bc560..62677be29a 100644
--- a/packages/malloy/src/lang/ast/field-space/query-spaces.ts
+++ b/packages/malloy/src/lang/ast/field-space/query-spaces.ts
@@ -50,6 +50,7 @@ import {
   emptyCompositeFieldUsage,
   emptyNarrowedCompositeFieldResolution,
   isEmptyCompositeFieldUsage,
+  joinedCompositeFieldUsage,
   mergeCompositeFieldUsage,
   narrowCompositeFieldResolution,
   NarrowedCompositeFieldResolution,
@@ -220,9 +221,10 @@ export abstract class QueryOperationSpace
     const lookup = this.exprSpace.lookup(reference);
     // Should always be found...
     if (lookup.found && lookup.found instanceof StructSpaceFieldBase) {
-      return (
+      return joinedCompositeFieldUsage(
+        joinPath.slice(0, -1),
         lookup.found.fieldDef().onCompositeFieldUsage ??
-        emptyCompositeFieldUsage()
+          emptyCompositeFieldUsage()
       );
     }
     throw new Error('Unexpected join lookup was not found or not a struct');
diff --git a/packages/malloy/src/lang/test/query.spec.ts b/packages/malloy/src/lang/test/query.spec.ts
index 1984541367..d6e2cb10c7 100644
--- a/packages/malloy/src/lang/test/query.spec.ts
+++ b/packages/malloy/src/lang/test/query.spec.ts
@@ -777,6 +777,19 @@ describe('query:', () => {
         group_by: b.ai
       }`).toTranslate();
     });
+    test('reference field in double nested join inside nest', () => {
+      expect(`
+        source: a_2 is a extend { join_one: b is b extend {
+          join_one: c is b on 1 = c.ai
+        } with astr }
+
+        run: a_2 -> {
+          nest: x is {
+            group_by: ai is b.c.ai
+          }
+        }
+      `).toTranslate();
+    });
     test.skip('reference join as field', () => {
       expect(`run: a -> {
         extend: { join_one: b with astr }