SERVER-43816 Push $text and $meta:"textScore" sort into the PlanStage layer.

This change involves unifying the behavior of find and
agg for validation of $meta:"textScore". In particular, find
operations no longer require a "textScore" $meta projection
in order to specify a "textScore" $meta sort. This brings
find into alignment with agg, which never had such a
restriction. It is also now legal for a find command to
sort on the field overridden by a $meta:"textScore" projection
without specifying the $meta operator in the sort pattern.

In addition:
 - Tightens validation around uses of "textScore" $meta
 projections for queries that do not specify a $text
 predicate.
 - Fixes a bug in which $natural sort/hint were not
 correctly validated.

1 files changed, 0 insertions, 14 deletions

diff --git a/src/mongo/db/query/query_planner_tree_test.cpp b/src/mongo/db/query/query_planner_tree_test.cpp
index e875163254d..a5c68dd6c03 100644
--- a/src/mongo/db/query/query_planner_tree_test.cpp
+++ b/src/mongo/db/query/query_planner_tree_test.cpp
@@ -815,20 +815,6 @@ TEST_F(QueryPlannerTest, TooManyToExplode) {
         "{pattern: {a: 1, b: 1, c:1, d:1}}}}}}}}}");
 }
 
-TEST_F(QueryPlannerTest, CantExplodeMetaSort) {
-    addIndex(BSON("a" << 1 << "b" << 1 << "c"
-                      << "text"));
-    runQuerySortProj(fromjson("{a: {$in: [1, 2]}, b: {$in: [3, 4]}}"),
-                     fromjson("{c: {$meta: 'textScore'}}"),
-                     fromjson("{c: {$meta: 'textScore'}}"));
-
-    assertNumSolutions(1U);
-    assertSolutionExists(
-        "{proj: {spec: {c:{$meta:'textScore'}}, node: "
-        "{sort: {pattern: {c:{$meta:'textScore'}}, limit: 0, node: {sortKeyGen: {node: "
-        "{cscan: {filter: {a:{$in:[1,2]},b:{$in:[3,4]}}, dir: 1}}}}}}}}");
-}
-
 // SERVER-13618: test that exploding scans for sort works even
 // if we must reverse the scan direction.
 TEST_F(QueryPlannerTest, ExplodeMustReverseScans) {