Organises linter errors and check tests/ directory

tox.ini

@@ -16,10 +16,38 @@ commands =
 
 [testenv:pep8]
 deps = flake8
-commands = flake8 buildozer/
+commands = flake8 buildozer/ tests/
 
 [flake8]
 ignore =
-    E121, E122, E123, E125, E126, E127, E128, E129, E131, E226, E231, E241,
-    E262, E265, E301, E302, E303, E305, E402, E501, E502, E722, E731, E741,
-    F401, F821, F841, W391, W504, W605
+    E121, # continuation line under-indented for hanging indent
+    E122, # continuation line missing indentation or outdented
+    E123, # closing bracket does not match indentation of opening bracket's line
+    E125, # continuation line with same indent as next logical line
+    E126, # continuation line over-indented for hanging indent
+    E127, # continuation line over-indented for visual indent
+    E128, # continuation line under-indented for visual indent
+    E129, # visually indented line with same indent as next logical line
+    E131, # continuation line unaligned for hanging indent
+    E226, # missing whitespace around arithmetic operator
+    E231, # missing whitespace after ','
+    E241, # multiple spaces after ','
+    E262, # inline comment should start with '# '
+    E265, # block comment should start with '# '
+    E301, # expected 1 blank line, found 0
+    E302, # expected 2 blank lines, found 1
+    E303, # too many blank lines
+    E305, # expected 2 blank lines after class or function definition, found 1
+    E402, # module level import not at top of file
+    E501, # line too long
+    E502, # the backslash is redundant between brackets
+    E722, # do not use bare 'except'
+    E731, # do not assign a lambda expression, use a def
+    E741, # ambiguous variable name
+    F401, # imported but unused
+    F821, # undefined name
+    F841, # local variable is assigned to but never used
+    W391, # blank line at end of file
+    W503, # line break before binary operator
+    W504, # line break after binary operator
+    W605  # invalid escape sequence