how to make a Python Test Driven Development environment automatically

To review, here are steps I take to make the environment for every project

I want to give one command for the program to do every step except

give the project a name
make the test pass and
work on the project

I only want to do 3 steps not 18

preview

Here is the program_ I have by the end of the chapter to automatically make a python test driven development environment, it is only 28 lines of code, with spaces

#!/bin/bash
mkdir more_magic
cd more_magic
mkdir src
touch src/more_magic.py
mkdir tests
touch tests/__init__.py

echo "import unittest


class TestMoreMagic(unittest.TestCase):

    def test_failure(self):
        self.assertFalse(True)


# Exceptions seen
# AssertionError
" > tests/test_more_magic.py

python3 -m venv .venv
source .venv/bin/activate
python3 -m pip install --upgrade pip
echo "pytest-watch" > requirements.txt
python3 -m pip install --requirement requirements.txt
pytest-watch

questions about making a Python Test Driven Development Environment automatically

Here are questions you can answer after going through this chapter

How can I make a shell script?
How can I view the permissions of a file?
How can I make a shell script run as a command
How can I run a shell script

how to make a shell script

I go to the terminal_ and use touch_ to make an empty file_ with a name that is easy to remember later. I want the name to also describe the program_ that will automatically make a Test Driven Development environment for me
```
touch makePythonTdd.sh
```
the terminal_ goes back to the command line

I open makePythonTdd.sh in the editor of the `Integrated Development Environment (IDE)`_, then add the commands I use to make a Python_ Test Driven Development environment for a project

#!/bin/bash
mkdir magic_again
cd magic_again
mkdir src
touch src/magic_again.py
mkdir tests
touch tests/__init__.py
touch tests/test_magic_again.py
python3 -m venv .venv
source .venv/bin/activate
python3 -m pip install --upgrade pip
echo "pytest-watch" > requirements.txt
python3 -m pip install --requirement requirements.txt
pytest-watch

#!/bin/bash is called a shebang_ line, it tells the computer to use bash_ to run this program_

test_magic_again.py is an empty file_ because I used touch_. I want it to have the text for the first failure so I do not have to open the editor to add the text for it in each project. I use echo_ instead of touch_ to make the makePythonTdd.sh program_ add the text to test_magic_again.py when it makes the file_ in the tests folder_, the same I do with the requirements.txt file_
```
 6mkdir tests
 7touch tests/__init__.py
 8
 9echo "" > tests/test_magic_again.py
10
11python3 -m venv .venv
12source .venv/bin/activate
```
I add the text for the test inside the quotes (“”) I just added to makePythonTdd.sh, the way I do with echo_ when I add "pytest-watch" as text in requirements.txt

Caution

Indentation_ is important in Python_, I use 4 spaces as convention in this book, see the Python Style Guide for more
```
 9echo "import unittest
10
11
12class TestMagicAgain(unittest.TestCase):
13
14    def test_failure(self):
15        self.assertFalse(True)
16
17
18# Exceptions seen
19# AssertionError
20" > tests/test_magic_again.py
```

how to run a shell script

I go back to the terminal_ to run the program_

makePythonTdd.sh

the terminal_ shows

command not found: makePythonTdd.sh

I have to tell the computer where the file_ is

./makePythonTdd.sh

./ is shorthand for this directory which in this case is pumping_python where makePythonTdd.sh is saved. The computer checks a few directories_ when a command is given. Those directories are where commands like mkdir_, cd_, tree_ and echo_ are saved. The terminal_ shows

permission denied: ./makePythonTdd.sh

I want to make sure the computer can run the program_. I have to make it executable

how to view the permissions of a file

I use ls_ to check the permissions of the file_

ls -l makePythonTdd.sh

-l is the option to show the long listing format which includes permissions for the file_

the terminal_ shows

-rw-r--r-- 1 abcdef ghijk XX Month  Y ZA:BC makePythonTdd.sh

the first 10 characters above (-rw-r--r--) are grouped

-    rw-    r--    r--

the groups that have 3 characters show read, write and execute permissions with

r for read
w for write and
x for execute

here is what it means for makePythonTdd.sh

the first group tells if this is file_ or directory_ : - means this is a regular file_, it is not a directory_
this group shows permissions for the owner of the thing: rw- means the owner of the file_ can read and write to the file_ but NOT execute it
this group shows permissions for the group of the owner of the thing: r-- means the group can read the file_, NOT write to it or execute it
this group is for other users: r-- means other users can read the file_, NOT write to it or execute it

I want to add execute permissions so I can run the file

how to make a shell script run as a command

I change the mode of the file_ to add executable permissions
```
chmod +x makePythonTdd.sh
```
chmod_ is a program_ that changes the mode (permissions) of the given file_, the terminal_ goes back to the command line
I list the permissions again with ls_
```
ls -l makePythonTdd.sh
```
the terminal_ shows
```
-rwxr-xr-x 1 abcdef ghijk XX Month  Y ZA:BC makePythonTdd.sh
```
here is what each one of the characters before the folder_ means
- - means this is a regular file_, it is not a directory_
- rwx means the owner of the file_ has permissions to read, write to and execute it
- r-x means the group the owner of the file_ belongs to has permissions to read and execute the file_ they cannot write to it, and the second
- r-x means other users have permissions to read and execute the file_, they cannot write to it

I try the command again

./makePythonTdd.sh

the terminal_ shows

======================================= FAILURES =======================================
_____________________________ TestMagicAgain.test_failure ______________________________

self = <tests.test_magic_again.TestMagicAgain testMethod=test_failure>

    def test_failure(self):
>       self.assertFalse(True)
E       AssertionError: True is not false

tests/test_magic_again.py:7: AssertionError
=============================== short test summary info ================================
FAILED tests/test_magic_again.py::TestMagicAgain::test_failure - AssertionError: True is not false
================================== 1 failed in X.YZs ===================================

Success! I just made a program_ that can make the magic_again project anytime I want and it automatically does the steps I did manually.

I hold ctrl on the keyboard and click on tests/test_magic_again.py to open it in the editor then make the test pass
I hit ctrl+c in the terminal_ to stop the test

I want to use makePythonTdd.sh to make another project with a different name. I change magic_again to the name of the new project in the editor

Note

The lines that are changing in the code are highlighted

#!/bin/bash
mkdir more_magic
cd more_magic
mkdir src
touch src/more_magic.py
mkdir tests
touch tests/__init__.py

echo "import unittest


class TestMoreMagic(unittest.TestCase):

    def test_failure(self):
        self.assertFalse(True)


# Exceptions seen
# AssertionError
" > tests/test_more_magic.py

I run makePythonTdd.sh in the terminal_ to make a project named more_magic

./makePythonTdd.sh

the terminal_ shows AssertionError

======================================= FAILURES =======================================
______________________________ TestMoreMagic.test_failure ______________________________

self = <tests.test_more_magic.TestMoreMagic testMethod=test_failure>

    def test_failure(self):
>       self.assertFalse(True)
E       AssertionError: True is not false

tests/test_more_magic.py:7: AssertionError
=============================== short test summary info ================================
FAILED tests/test_more_magic.py::TestMoreMagic::test_failure - AssertionError: True is not false
================================== 1 failed in X.YZs ===================================

I make the test pass

I hit ctrl+c to exit the tests in the terminal_

the program_ works and can make a Python_ Test Driven Development environment automatically the way I want every time

close the project

I close the test_more_magic.py in the editor I had open
I click in the terminal_ and exit the tests with ctrl+c on the keyboard
I `change directory`_ to the parent of more_magic
```
cd ..
```
the terminal_ shows
```
.../pumping_python
```
I am back in the pumping_python directory_

review

`Computer Programming`_ allows me to take some steps and make them a one line command for the computer to do for me. You have seen a way I can make a Python_ Test Driven Development environment, with a program to do it on any Linux_, Windows_ or MacOS_ computers.

How many questions can you answer after going through this chapter?

code from the chapter

Do you want to see all the CODE I typed in this chapter?

what is next?

Here is what we have gone through together so far

Would you like to use makePythonTdd.sh to make a Python Test Driven Development environment to test that an Exception is raised?

rate pumping python

If this has been a 7 star experience for you, please leave a 5 star review. It helps other people get into the book too

how to make a test driven development environment part 2

how to make a Python Test Driven Development environment automatically on Windows without Windows Subsystem for Linux