[PATCH v3 05/20] avocado/tasst: Type checking helpers

[David Gibson <david@gibson.dropbear.id.au>]

Add some helper functions for typechecking parameters.  We will be using
these so that accidentally misusing some of the upcoming test helpers will
result in more useful error messages.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 avocado/tasst/typing.py | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 avocado/tasst/typing.py

diff --git a/avocado/tasst/typing.py b/avocado/tasst/typing.py
new file mode 100644
index 0000000..2021b0b
--- /dev/null
+++ b/avocado/tasst/typing.py
@@ -0,0 +1,23 @@
+#! /usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# tasst - Test A Simple Socket Transport
+#         library of test helpers for passt & pasta
+#
+# tasst/typing.py - Type checking and related helpers
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+
+def typecheck(val, ty_):
+    if not isinstance(val, ty_):
+        raise TypeError("Expected {} instead of {}".format(ty_, type(val)))
+    return val
+
+
+def typecheck_default(val, ty_, default):
+    if val is None:
+        return default
+    return typecheck(val, ty_)
-- 
@@ -0,0 +1,23 @@
+#! /usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# tasst - Test A Simple Socket Transport
+#         library of test helpers for passt & pasta
+#
+# tasst/typing.py - Type checking and related helpers
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+
+def typecheck(val, ty_):
+    if not isinstance(val, ty_):
+        raise TypeError("Expected {} instead of {}".format(ty_, type(val)))
+    return val
+
+
+def typecheck_default(val, ty_, default):
+    if val is None:
+        return default
+    return typecheck(val, ty_)
-- 
2.40.1