Hi @mmahut, what follows is a general review and then a more detailed
one for each commit.

Each package should reference its depedencies directly instead of
using pythonPackages. And in general we need to enable tests
which may require fetching from github.

• pythonPackages.PTable: init at 0.9.2

Please normalize the attribute name to ptable and also pname.

note you'll need to manually give fetchPypi the non normalized pname

The commit msg should reflect this change.

Also we should build from the latest commit on GitHub, see kxxoling/PTable#27.
You'll then will be able to enable the tests.

• pythonPackages.inquirer: init at 2.6.3

Please enable tests.
Looking at requirements-dev.txt and the Makefile will be helpful.

• pythonPackages.readchar: init at 2.0.1

Fetching from PyPi's wheels appear to be to complex and it won't be automatically updated.
Please use fetchFromGitHub and enable tests. The setup_requires will need to be in nativeBuildInputs btw.

• pythonPackages.validate_email: init at 1.3

Please normalize the attribute name to validate-email and also pname.
The commit msg should reflect this change.

• pythonPackages.togglCli: init at 2.1.0

Please normalize the attribute name to toggle-cli and also pname.
The commit msg should reflect this change.

We also need to correct the dependency declaration for the setup_requires pbr and twine.
They should be nativeBuildInputs and pbr should also be a checkInputs because we need it for tests.

And on the topic of tests we should enable them.

• Adding pythonPackages.{togglCli,validate_email,readchar,PTable,inquirer}

Unfortunately this is going to require some git rewriting because each commit that
inits should also add itself to python-packages.nix.

I've built everything successfully for all interpreters in nixpkgs ❇️

Managed to fix the tests for toggl-cli by skipping one's that still somehow needed network access
(probably needs to be fixed upstream)

diff --git a/pkgs/development/python-modules/toggl-cli/default.nix b/pkgs/development/python-modules/toggl-cli/default.nix
index c44b42b6f2a..5c851fdb475 100644
--- a/pkgs/development/python-modules/toggl-cli/default.nix
+++ b/pkgs/development/python-modules/toggl-cli/default.nix
@@ -24,11 +24,18 @@ buildPythonPackage rec {
   nativeBuildInputs = [ pbr twine ];
   checkInputs = [ pbr pytest pytestcov pytest-mock faker factory_boy ];
 
-  # FIXME: fix tests
-  doCheck = false;
+  preCheck = ''
+     export TOGGL_API_TOKEN=your_api_token
+     export TOGGL_PASSWORD=toggl_password
+     export TOGGL_USERNAME=user@example.com
+  '';
 
   checkPhase = ''
-   pytest -m "not premium" tests/unit
+    runHook preCheck
+
+    pytest -k "not premium and not TestDateTimeType and not TestDateTimeField" tests/unit --maxfail=20
+
+    runHook postCheck
   '';
 
   propagatedBuildInputs = [

Also pr'd something for the readchar pin in inquirer magmax/python-inquirer#77

Following comments are just some expression cleanup.