fix(localstore): corrupt reserve size (#2735)

Fixes a bug where incorrect reserve size bookkeeping was done on Put calls that were using a variadic number of parameters.

pkg/localstore/gc.go

@@ -374,7 +374,7 @@ func (db *DB) evictReserve() (totalEvicted uint64, done bool, err error) {
 	if err != nil {
 		return 0, false, err
 	}
-	if reserveSizeStart == target {
+	if reserveSizeStart <= target {
 		return 0, true, nil
 	}
 

pkg/localstore/localstore_test.go

@@ -381,7 +381,7 @@ func newItemsCountTest(i shed.Index, want int) func(t *testing.T) {
 	}
 }
 
-// newIndexGCSizeTest retruns a test function that validates if DB.gcSize
+// newIndexGCSizeTest returns a test function that validates if DB.gcSize
 // value is the same as the number of items in DB.gcIndex.
 func newIndexGCSizeTest(db *DB) func(t *testing.T) {
 	return func(t *testing.T) {
@@ -405,6 +405,22 @@ func newIndexGCSizeTest(db *DB) func(t *testing.T) {
 	}
 }
 
+// reserveSizeTest checks that the reserveSize scalar is equal
+// to the expected value.
+func reserveSizeTest(db *DB, want uint64) func(t *testing.T) {
+	return func(t *testing.T) {
+		t.Helper()
+
+		got, err := db.reserveSize.Get()
+		if err != nil {
+			t.Fatal(err)
+		}
+		if got != want {
+			t.Errorf("got reserve size %v, want %v", got, want)
+		}
+	}
+}
+
 // testIndexChunk embeds storageChunk with additional data that is stored
 // in database. It is used for index values validations.
 type testIndexChunk struct {