[DEV-326] Fixed ffldb tests broken in Windows (#153)

* [DEV-326] Worked around a parallelism issue in go test. Fixed a test where a file was being deleted while still open.

* [DEV-326] Worked around a timer-related oddity.

* [DEV-326] Fixed closing a file twice.

* [DEV-326] Using pdb.closed instead of an additional variable.

database/ffldb/blockio_test.go

@@ -29,7 +29,11 @@ func TestDeleteFile(t *testing.T) {
 	for _, test := range tests {
 		func() {
 			pdb := newTestDb("TestDeleteFile", t)
-			defer pdb.Close()
+			defer func() {
+				if !pdb.closed {
+					pdb.Close()
+				}
+			}()
 
 			err := pdb.Update(func(dbTx database.Tx) error {
 				dbTx.StoreBlock(testBlock)
@@ -39,6 +43,11 @@ func TestDeleteFile(t *testing.T) {
 				t.Fatalf("TestDeleteFile: Error storing block: %s", err)
 			}
 
+			err = pdb.Close()
+			if err != nil {
+				t.Fatalf("TestDeleteFile: Error closing file before deletion: %s", err)
+			}
+
 			err = pdb.store.deleteFile(test.fileNum)
 			if (err != nil) != test.expectedErr {
 				t.Errorf("TestDeleteFile: %d: Expected error status: %t, but got: %t",

database/ffldb/common_test.go

@@ -13,7 +13,7 @@ import (
 )
 
 func newTestDb(testName string, t *testing.T) *db {
-	dbPath := path.Join(os.TempDir(), "db_test")
+	dbPath := path.Join(os.TempDir(), "db_test", testName)
 	err := os.RemoveAll(dbPath)
 	if err != nil && !os.IsNotExist(err) {
 		t.Fatalf("%s: Error deleting database folder before starting: %s", testName, err)

database/ffldb/dbcache.go

@@ -533,7 +533,7 @@ func (c *dbCache) flush() error {
 func (c *dbCache) needsFlush(tx *transaction) bool {
 	// A flush is needed when more time has elapsed than the configured
 	// flush interval.
-	if time.Since(c.lastFlush) > c.flushInterval {
+	if time.Since(c.lastFlush) >= c.flushInterval {
 		return true
 	}