[PATCH v4 20/24] python: add pytest and tests

[John Snow]

Try using pytest to manage our various tests; even though right now
they're only invoking binaries and not really running any python-native
code.

Create tests/, and add test_lint.py which calls out to mypy, flake8,
pylint and isort to enforce the standards in this directory.

Add pytest to the setup.cfg development dependencies; add a pytest
configuration section as well; run it in verbose mode.

Finally, add pytest to the Pipfile environment and lock the new
dependencies.

Provided you have the right development dependencies (mypy, flake8,
isort, pylint, and now pytest) You should be able to run "pytest" from
the python folder to run all of these linters with the correct
arguments.

Signed-off-by: John Snow <jsnow@redhat.com>
---
 python/Pipfile.lock       | 57 ++++++++++++++++++++++++++++++++++++++-
 python/setup.cfg          |  5 ++++
 python/tests/test_lint.py | 28 +++++++++++++++++++
 3 files changed, 89 insertions(+), 1 deletion(-)
 create mode 100644 python/tests/test_lint.py

diff --git a/python/Pipfile.lock b/python/Pipfile.lock
index 85b3124a491..0fa1a14a9b2 100644
--- a/python/Pipfile.lock
+++ b/python/Pipfile.lock
@@ -30,6 +30,14 @@
             "markers": "python_version >= '3.5'",
             "version": "==2.4.2"
         },
+        "attrs": {
+            "hashes": [
+                
"sha256:31b2eced602aa8423c2aea9c76a724617ed67cf9513173fd3a4f03e3a929c7e6",
+                
"sha256:832aa3cde19744e49938b91fea06d69ecb9e649c93ba974535d08ad92164f700"
+            ],
+            "markers": "python_version >= '2.7' and python_version not in 
'3.0, 3.1, 3.2, 3.3'",
+            "version": "==20.3.0"
+        },
         "flake8": {
             "hashes": [
                 
"sha256:749dbbd6bfd0cf1318af27bf97a14e28e5ff548ef8e5b1566ccfb25a11e7c839",
@@ -43,9 +51,16 @@
                 
"sha256:ace61d5fc652dc280e7b6b4ff732a9c2d40db2c0f92bc6cb74e07b73d53a1771",
                 
"sha256:fa5daa4477a7414ae34e95942e4dd07f62adf589143c875c133c1e53c4eff38d"
             ],
-            "markers": "python_version < '3.8'",
+            "markers": "python_version < '3.8' and python_version < '3.8'",
             "version": "==3.4.0"
         },
+        "iniconfig": {
+            "hashes": [
+                
"sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3",
+                
"sha256:bc3af051d7d14b2ee5ef9969666def0cd1a000e121eaea580d4a313df4b37f32"
+            ],
+            "version": "==1.1.1"
+        },
         "isort": {
             "hashes": [
                 
"sha256:c729845434366216d320e936b8ad6f9d681aab72dc7cbc2d51bedc3582f3ad1e",
@@ -123,6 +138,30 @@
             ],
             "version": "==0.4.3"
         },
+        "packaging": {
+            "hashes": [
+                
"sha256:5b327ac1320dc863dca72f4514ecc086f31186744b84a230374cc1fd776feae5",
+                
"sha256:67714da7f7bc052e064859c05c595155bd1ee9f69f76557e21f051443c20947a"
+            ],
+            "markers": "python_version >= '2.7' and python_version not in 
'3.0, 3.1, 3.2, 3.3'",
+            "version": "==20.9"
+        },
+        "pluggy": {
+            "hashes": [
+                
"sha256:15b2acde666561e1298d71b523007ed7364de07029219b604cf808bfa1c765b0",
+                
"sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"
+            ],
+            "markers": "python_version >= '2.7' and python_version not in 
'3.0, 3.1, 3.2, 3.3'",
+            "version": "==0.13.1"
+        },
+        "py": {
+            "hashes": [
+                
"sha256:21b81bda15b66ef5e1a777a21c4dcd9c20ad3efd0b3f817e7a809035269e1bd3",
+                
"sha256:3b80836aa6d1feeaa108e046da6423ab8f6ceda6468545ae8d02d9d58d18818a"
+            ],
+            "markers": "python_version >= '2.7' and python_version not in 
'3.0, 3.1, 3.2, 3.3'",
+            "version": "==1.10.0"
+        },
         "pycodestyle": {
             "hashes": [
                 
"sha256:2295e7b2f6b5bd100585ebcb1f616591b652db8a741695b3d8f5d28bdc934367",
@@ -147,6 +186,22 @@
             "markers": "python_version >= '3.5'",
             "version": "==2.6.0"
         },
+        "pyparsing": {
+            "hashes": [
+                
"sha256:c203ec8783bf771a155b207279b9bccb8dea02d8f0c9e5f8ead507bc3246ecc1",
+                
"sha256:ef9d7589ef3c200abe66653d3f1ab1033c3c419ae9b9bdb1240a85b024efc88b"
+            ],
+            "markers": "python_version >= '2.6' and python_version not in 
'3.0, 3.1, 3.2'",
+            "version": "==2.4.7"
+        },
+        "pytest": {
+            "hashes": [
+                
"sha256:9d1edf9e7d0b84d72ea3dbcdfd22b35fb543a5e8f2a60092dd578936bf63d7f9",
+                
"sha256:b574b57423e818210672e07ca1fa90aaf194a4f63f3ab909a2c67ebb22913839"
+            ],
+            "markers": "python_version >= '3.6'",
+            "version": "==6.2.2"
+        },
         "qemu": {
             "editable": true,
             "path": "."
diff --git a/python/setup.cfg b/python/setup.cfg
index 11c361501e8..2c5943277d7 100644
--- a/python/setup.cfg
+++ b/python/setup.cfg
@@ -26,6 +26,7 @@ devel =
     isort >= 5.0.5
     mypy >= 0.770
     pylint >= 2.6.0
+    pytest >= 3.0.0
 
 
 [flake8]
@@ -73,3 +74,7 @@ include_trailing_comma=True
 line_length=72
 lines_after_imports=2
 multi_line_output=3
+
+[tool:pytest]
+addopts = -v
+console_output_style = count
diff --git a/python/tests/test_lint.py b/python/tests/test_lint.py
new file mode 100644
index 00000000000..38fefa01c66
--- /dev/null
+++ b/python/tests/test_lint.py
@@ -0,0 +1,28 @@
+import subprocess
+
+
+def _external_test(command_line: str) -> None:
+    args = command_line.split(' ')
+    try:
+        subprocess.run(args, check=True)
+    except subprocess.CalledProcessError as err:
+        # Re-contextualize to avoid pytest showing error context inside
+        # the subprocess module itself
+        raise Exception("'{:s}' returned {:d}".format(
+            ' '.join(args), err.returncode)) from None
+
+
+def test_isort() -> None:
+    _external_test('isort -c qemu')
+
+
+def test_flake8() -> None:
+    _external_test('flake8')
+
+
+def test_pylint() -> None:
+    _external_test('pylint qemu')
+
+
+def test_mypy() -> None:
+    _external_test('mypy -p qemu')
-- 
2.29.2