fix(federation): use out_edges_with_federation_self_edges in query …

…builder (#6127)

apollo-federation/src/query_graph/build_query_graph.rs

@@ -1572,8 +1572,8 @@ impl FederatedQueryGraphBuilder {
                     Selection::Field(field_selection) => {
                         let existing_edge_info = base
                             .query_graph
-                            .graph
-                            .edges_directed(node, Direction::Outgoing)
+                            .out_edges_with_federation_self_edges(node)
+                            .into_iter()
                             .find_map(|edge_ref| {
                                 let edge_weight = edge_ref.weight();
                                 let QueryGraphEdgeTransition::FieldCollection {
@@ -1697,8 +1697,8 @@ impl FederatedQueryGraphBuilder {
                             // construction.
                             let (edge, tail) = base
                                 .query_graph
-                                .graph
-                                .edges_directed(node, Direction::Outgoing)
+                                .out_edges_with_federation_self_edges(node)
+                                .into_iter()
                                 .find_map(|edge_ref| {
                                     let edge_weight = edge_ref.weight();
                                     let QueryGraphEdgeTransition::Downcast {
@@ -1810,11 +1810,7 @@ impl FederatedQueryGraphBuilder {
         new_node_weight.has_reachable_cross_subgraph_edges = has_reachable_cross_subgraph_edges;
 
         let mut new_edges = Vec::new();
-        for edge_ref in base
-            .query_graph
-            .graph
-            .edges_directed(node, Direction::Outgoing)
-        {
+        for edge_ref in base.query_graph.out_edges_with_federation_self_edges(node) {
             let edge_tail = edge_ref.target();
             let edge_weight = edge_ref.weight();
             new_edges.push(QueryGraphEdgeData {

apollo-federation/tests/query_plan/build_query_plan_tests/provides.rs

@@ -846,3 +846,73 @@ fn it_works_with_type_condition_even_for_types_only_reachable_by_the_at_provides
       "###
     );
 }
+
+#[test]
+fn test_provides_edge_ordering() {
+    let planner = planner!(
+        SubgraphQ: r#"
+type A {
+    id: ID! @external
+}
+
+type Query {
+    test: A @provides(fields: "id")
+}
+        "#,
+        SubgraphX: r#"
+type A @key(fields: "id") {
+    id: ID!
+    data: String! @shareable
+}
+        "#,
+        SubgraphY: r#"
+type A @key(fields: "id") {
+    id: ID!
+    data: String! @shareable
+}
+        "#,
+    );
+
+    assert_plan!(
+        &planner,
+        r#"
+{
+    test { # provides id
+        data
+    }
+}
+        "#,
+
+        // Make sure @provides edges are ordered as expected.
+        // `data` is expected to be fetched from SubgraphX, not SubgraphY.
+        @r###"
+    QueryPlan {
+      Sequence {
+        Fetch(service: "SubgraphQ") {
+          {
+            test {
+              __typename
+              id
+            }
+          }
+        },
+        Flatten(path: "test") {
+          Fetch(service: "SubgraphX") {
+            {
+              ... on A {
+                __typename
+                id
+              }
+            } =>
+            {
+              ... on A {
+                data
+              }
+            }
+          },
+        },
+      },
+    }
+    "###
+    );
+}

apollo-federation/tests/query_plan/supergraphs/test_provides_edge_ordering.graphql

@@ -0,0 +1,64 @@
+# Composed from subgraphs with hash: f5cb1210587d45fee11b9c57247d6c570d0ae7fd
+schema
+  @link(url: "https://specs.apollo.dev/link/v1.0")
+  @link(url: "https://specs.apollo.dev/join/v0.4", for: EXECUTION)
+{
+  query: Query
+}
+
+directive @join__directive(graphs: [join__Graph!], name: String!, args: join__DirectiveArguments) repeatable on SCHEMA | OBJECT | INTERFACE | FIELD_DEFINITION
+
+directive @join__enumValue(graph: join__Graph!) repeatable on ENUM_VALUE
+
+directive @join__field(graph: join__Graph, requires: join__FieldSet, provides: join__FieldSet, type: String, external: Boolean, override: String, usedOverridden: Boolean, overrideLabel: String) repeatable on FIELD_DEFINITION | INPUT_FIELD_DEFINITION
+
+directive @join__graph(name: String!, url: String!) on ENUM_VALUE
+
+directive @join__implements(graph: join__Graph!, interface: String!) repeatable on OBJECT | INTERFACE
+
+directive @join__type(graph: join__Graph!, key: join__FieldSet, extension: Boolean! = false, resolvable: Boolean! = true, isInterfaceObject: Boolean! = false) repeatable on OBJECT | INTERFACE | UNION | ENUM | INPUT_OBJECT | SCALAR
+
+directive @join__unionMember(graph: join__Graph!, member: String!) repeatable on UNION
+
+directive @link(url: String, as: String, for: link__Purpose, import: [link__Import]) repeatable on SCHEMA
+
+type A
+  @join__type(graph: SUBGRAPHQ)
+  @join__type(graph: SUBGRAPHX, key: "id")
+  @join__type(graph: SUBGRAPHY, key: "id")
+{
+  id: ID! @join__field(graph: SUBGRAPHQ, external: true) @join__field(graph: SUBGRAPHX) @join__field(graph: SUBGRAPHY)
+  data: String! @join__field(graph: SUBGRAPHX) @join__field(graph: SUBGRAPHY)
+}
+
+scalar join__DirectiveArguments
+
+scalar join__FieldSet
+
+enum join__Graph {
+  SUBGRAPHQ @join__graph(name: "SubgraphQ", url: "none")
+  SUBGRAPHX @join__graph(name: "SubgraphX", url: "none")
+  SUBGRAPHY @join__graph(name: "SubgraphY", url: "none")
+}
+
+scalar link__Import
+
+enum link__Purpose {
+  """
+  `SECURITY` features provide metadata necessary to securely resolve fields.
+  """
+  SECURITY
+
+  """
+  `EXECUTION` features provide metadata necessary for operation execution.
+  """
+  EXECUTION
+}
+
+type Query
+  @join__type(graph: SUBGRAPHQ)
+  @join__type(graph: SUBGRAPHX)
+  @join__type(graph: SUBGRAPHY)
+{
+  test: A @join__field(graph: SUBGRAPHQ, provides: "id")
+}