SERVER-15033 Implement SimpleRecordStoreV1::truncate()

1 files changed, 44 insertions, 0 deletions

diff --git a/jstests/core/collection_truncate.js b/jstests/core/collection_truncate.js
new file mode 100644
index 00000000000..1581762f30a
--- /dev/null
+++ b/jstests/core/collection_truncate.js
@@ -0,0 +1,44 @@
+// SERVER-15033 truncate on a regular collection
+
+var t = db.getCollection('collection_truncate');
+t.drop();
+
+function truncate() {
+    // Until SERVER-15274 is implemented, this is the only way to truncate a collection.
+    assert.commandWorked(t.runCommand('emptycapped')); // works on non-capped as well.
+}
+
+function assertEmpty() {
+    var stats = t.stats();
+
+    assert.eq(stats.count, 0);
+    assert.eq(stats.size, 0);
+
+    if ('numExtents' in stats) {
+        assert.lte(stats.numExtents, 1);
+    }
+
+    assert.eq(t.count(), 0);
+    assert.eq(t.find().itcount(), 0);
+
+    var res = t.validate({full: true});
+    assert.commandWorked(res);
+    assert(res.valid, "failed validate(): " + tojson(res));
+}
+
+// Single record case.
+t.insert({a:1});
+truncate();
+assertEmpty();
+
+// Multi-extent case.
+var initialStorageSize = t.stats().storageSize;
+while (t.stats().storageSize == initialStorageSize) {
+    t.insert({a:1});
+}
+truncate();
+assertEmpty();
+
+// Already empty case.
+truncate();
+assertEmpty();