SERVER-52929 Correctly handle compound indexes with 32 keys

(cherry picked from commit 957ddd678dbd49a96318a13e8f669567e4eba3ab)

1 files changed, 57 insertions, 0 deletions

diff --git a/jstests/core/compound_index_max_fields.js b/jstests/core/compound_index_max_fields.js
new file mode 100644
index 00000000000..63cd9224dff
--- /dev/null
+++ b/jstests/core/compound_index_max_fields.js
@@ -0,0 +1,57 @@
+/**
+ * Tests operations on indexes with the maximum number of compound index fields, 32.
+ *
+ *  @tags: [
+ *   assumes_unsharded_collection,
+ *   multiversion_incompatible,
+ *   requires_non_retryable_writes,
+ * ]
+ */
+(function() {
+
+const collName = jsTestName();
+const coll = db[collName];
+coll.drop();
+
+// Create a spec with alternating ascending and descending fields to keep things interesting.
+let spec = {};
+for (let i = 0; i < 32; i++) {
+    spec["f" + i] = (i % 2 == 0) ? 1 : -1;
+}
+
+assert.commandWorked(coll.createIndex(spec));
+assert.commandWorked(coll.insert({_id: 0}));
+for (let i = 0; i < 32; i++) {
+    assert.commandWorked(coll.update({_id: 0}, {
+        $set: {['f' + i]: 1},
+    }));
+}
+
+for (let i = 0; i < 32; i++) {
+    assert.eq(1, coll.find({['f' + i]: 1}).hint(spec).itcount());
+}
+
+// Create an index that has one too many fields.
+let bigSpec = Object.extend({'f32': -1}, spec);
+assert.commandFailedWithCode(coll.createIndex(bigSpec), 13103);
+
+coll.drop();
+
+// Create a unique version of the same index from before.
+assert.commandWorked(coll.createIndex(spec, {unique: true}));
+
+let doc = {};
+let doc2 = {};
+for (let i = 0; i < 32; i++) {
+    doc['f' + i] = 1;
+    doc2['f' + i] = 2;
+}
+
+assert.commandWorked(coll.insert(doc));
+assert.commandWorked(coll.insert(doc2));
+
+for (let i = 0; i < 32; i++) {
+    let query = {['f' + i]: 1};
+    assert.eq(2, coll.find().hint(spec).itcount(), "failed on query: " + tojson(query));
+}
+})();