Add nimble clean test

tests/tcleancommand.nim

@@ -0,0 +1,17 @@
+# Copyright (C) Nimble Authors. All rights reserved.
+# BSD License. Look at license.txt for more info.
+
+{.used.}
+
+import unittest, os
+import testscommon
+from nimblepkg/common import cd
+
+suite "nimble clean":
+  test "can clean":
+    cd "run":
+      check execNimbleYes("build").exitCode == QuitSuccess
+      check fileExists("run".addFileExt(ExeExt))
+
+      check execNimbleYes("clean").exitCode == QuitSuccess
+      check not fileExists("run".addFileExt(ExeExt))

tests/tester.nim

@@ -6,6 +6,7 @@ import testscommon
 # suits imports
 
 import tcheckcommand
+import tcleancommand
 import tdevelopfeature
 import tissues
 import tlocaldeps