[PATCH 08/27] tasst, avocado: Introduce library of common test helpers

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

Create a Python package "tasst" with common helper code for use in passt
and pasta.  Initially it just has some trivial typechecking helpers.

Extend the avocado-meta tests to include selftests within the tasst
library.  This lets us test the functionality of the library itself without
involving actual passt or pasta.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 test/Makefile           |  8 ++++---
 test/tasst/__init__.py  | 11 ++++++++++
 test/tasst/typecheck.py | 47 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 3 deletions(-)
 create mode 100644 test/tasst/__init__.py
 create mode 100644 test/tasst/typecheck.py

diff --git a/test/Makefile b/test/Makefile
index fc8d3a6f..c06d63b6 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -209,7 +209,8 @@ jammy-server-cloudimg-s390x.img:
 PYTHON = python3
 VENV = venv
 PLUGIN = avocado_classless
-PYPKGS = $(PLUGIN)/$(PLUGIN) $(wildcard $(PLUGIN)/*.py)
+PYPKGS = $(PLUGIN)/$(PLUGIN) $(wildcard $(PLUGIN)/*.py) \
+	tasst
 
 # Put this back if/when the plugin becomes available in upstream/system avocado
 #AVOCADO := $(shell which avocado)
@@ -229,11 +230,11 @@ avocado-assets:
 
 .PHONY: avocado
 avocado: avocado-assets $(VENV)
-	$(AVOCADO) run avocado
+	PYTHONPATH=. $(AVOCADO) run avocado
 
 .PHONY: avocado-meta
 avocado-meta: avocado-assets $(VENV)
-	$(AVOCADO) run $(PLUGIN)/selftests.py
+	PYTHONPATH=. $(AVOCADO) run $(PLUGIN)/selftests.py tasst
 
 flake8: $(VENV)
 	$(VENV)/bin/flake8 $(PYPKGS)
@@ -251,6 +252,7 @@ pylint: $(VENV)
 .PHONY: check
 check: avocado check-legacy
 
+.PHONY: clean
 clean: clean-legacy
 	$(RM) -r $(VENV)
 	find -name *~ | xargs $(RM)
diff --git a/test/tasst/__init__.py b/test/tasst/__init__.py
new file mode 100644
index 00000000..c1d5d9dd
--- /dev/null
+++ b/test/tasst/__init__.py
@@ -0,0 +1,11 @@
+#! /usr/bin/env python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+"""
+Test A Simple Socket Transport
+library of test helpers for passt & pasta
+"""
diff --git a/test/tasst/typecheck.py b/test/tasst/typecheck.py
new file mode 100644
index 00000000..f97fc401
--- /dev/null
+++ b/test/tasst/typecheck.py
@@ -0,0 +1,47 @@
+#! /usr/bin/env avocado-runner-avocado-classless
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+"""
+Test A Simple Socket Transport
+
+Type checking and related helpers
+"""
+
+from avocado_classless.test import test, assert_eq, assert_raises
+
+
+def typecheck(val, ty_):
+    """typecheck(val, ty_)
+
+    Return val, raising TypeError if it does not have type ty_.
+    """
+    if not isinstance(val, ty_):
+        raise TypeError(f'Expected {ty_} instead of {type(val)}')
+    return val
+
+
+@test
+def test_typecheck():
+    assert_eq(typecheck(17, int), 17)
+    assert_eq(typecheck("hello", str), "hello")
+    assert_raises(TypeError, typecheck, 17, str)
+
+
+def typecheck_default(val, ty_, default):
+    """typecheck_default(val, ty_, default)
+
+    If val is None, return default.  Otherwise return typecheck(val, ty_).
+    """
+    if val is None:
+        return default
+    return typecheck(val, ty_)
+
+
+@test
+def test_typecheck_default():
+    assert_eq(typecheck_default(17, int, None), 17)
+    assert_eq(typecheck_default(None, int, 17), 17)
-- 
@@ -0,0 +1,47 @@
+#! /usr/bin/env avocado-runner-avocado-classless
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+"""
+Test A Simple Socket Transport
+
+Type checking and related helpers
+"""
+
+from avocado_classless.test import test, assert_eq, assert_raises
+
+
+def typecheck(val, ty_):
+    """typecheck(val, ty_)
+
+    Return val, raising TypeError if it does not have type ty_.
+    """
+    if not isinstance(val, ty_):
+        raise TypeError(f'Expected {ty_} instead of {type(val)}')
+    return val
+
+
+@test
+def test_typecheck():
+    assert_eq(typecheck(17, int), 17)
+    assert_eq(typecheck("hello", str), "hello")
+    assert_raises(TypeError, typecheck, 17, str)
+
+
+def typecheck_default(val, ty_, default):
+    """typecheck_default(val, ty_, default)
+
+    If val is None, return default.  Otherwise return typecheck(val, ty_).
+    """
+    if val is None:
+        return default
+    return typecheck(val, ty_)
+
+
+@test
+def test_typecheck_default():
+    assert_eq(typecheck_default(17, int, None), 17)
+    assert_eq(typecheck_default(None, int, 17), 17)
-- 
2.41.0