added a test

apollographql · Oct 4, 2024 · 1809331 · 1809331
1 parent 135e89c
commit 1809331
Showing 1 changed file with 101 additions and 0 deletions.
diff --git a/apollo-federation/tests/query_plan/build_query_plan_tests/introspection_typename_handling.rs b/apollo-federation/tests/query_plan/build_query_plan_tests/introspection_typename_handling.rs
@@ -295,3 +295,104 @@ fn add_back_sibling_typename_to_interface_object() {
     "###
     );
 }
+
+#[test]
+fn test_indirect_branch_merging_with_typename_sibling() {
+    let planner = planner!(
+        Subgraph1: r#"
+            type Query {
+                test: T
+            }
+
+            interface T {
+                id: ID!
+            }
+
+            type A implements T @key(fields: "id") {
+                id: ID!
+            }
+
+            type B implements T @key(fields: "id") {
+                id: ID!
+            }
+        "#,
+        Subgraph2: r#"
+            interface T {
+                id: ID!
+                f: Int!
+            }
+
+            type A implements T @key(fields: "id") {
+                id: ID!
+                f: Int!
+            }
+
+            type B implements T @key(fields: "id") {
+                id: ID!
+                f: Int!
+            }
+        "#,
+    );
+    // This operation has two `f` selection instances: One with __typename sibling and one without.
+    // It creates multiple identical branches in the form of `... on A { f }` with different `f`.
+    // The query plan must chose one over the other, which is implementation specific.
+    // Currently, the last one is chosen.
+    assert_plan!(
+        &planner,
+        r#"
+            {
+                test {
+                    __typename
+                    f # <= This will have a sibling typename value.
+                    ... on A {
+                        f # <= This one will have no sibling typename.
+                    }
+                }
+            }
+        "#,
+        @r###"
+    QueryPlan {
+      Sequence {
+        Fetch(service: "Subgraph1") {
+          {
+            test {
+              __typename
+              ... on A {
+                __typename
+                id
+              }
+              ... on B {
+                __typename
+                id
+              }
+            }
+          }
+        },
+        Flatten(path: "test") {
+          Fetch(service: "Subgraph2") {
+            {
+              ... on A {
+                __typename
+                id
+              }
+              ... on B {
+                __typename
+                id
+              }
+            } =>
+            {
+              ... on A {
+                f
+              }
+              ... on B {
+                __typename
+                f
+              }
+            }
+          },
+        },
+      },
+    }
+    "###
+    );
+}