Git version control

Git version control

Git stores a history of project snapshots. GitHub is a repository hosting service; Git works without it and without a network connection. Download Git: https://git-scm.com/downloads. Check it with git --version. A local repository is enough for this lab.

Distinguish between the working directory, staging area, and repository (Fig. 1.17). After editing, changes are not yet in the staging area. git add stages the file's current state, and git commit saves the staged snapshot. If you edit the file again after add, you must stage the new changes again.

Figure 1.17. Git areas and movement of changes

Create .gitignore in the project directory:

.venv/
__pycache__/
*.py[cod]
.idea/
.env

For the first assignment, do not share individual IDE settings. Team projects sometimes keep parts of .idea by agreement. .gitignore does not hide files that are already tracked or remove secrets from history. Commit .gitignore itself, source code, the README, and the dependency specification.

git init -b main
git config user.name "Student Name"
git config user.email "[email protected]"
git status
git add main.py .gitignore
git commit -m "Add first Python program"
git log --oneline

Replace the example name and address with your own details. Without --global, these settings apply to the current repository, which is convenient on a shared classroom computer. On a personal device, you can set them globally. For future repositories, use git config --global init.defaultBranch main; the init -b main command above already explicitly sets the branch name for this project.

Screenshot

git init; status; add; commit; log –oneline; no .venv tracked

Figure 1.18. The first local commit

git diff shows changes between working files and the staging area, while git diff --staged shows staged changes relative to the latest commit. git status explains the current state. Before restoring a file with git restore, save any edits you need: uncommitted changes may be lost. For a beginner, learning to read a diff is more useful than memorizing undo commands.

Make three meaningful commits: a working script; dependencies and their specification; instructions for running and checking the project. Do not create empty commits just to meet a count. Guide: https://git-scm.com/book/en/v2.

Git in PyCharm and optional publishing

If no repository exists yet, use VCS → Create Git Repository or the command for enabling version control available in your interface. The Commit window shows files and their diffs; the message should explain the change. In the default keymap, Alt+0 opens Commit, and Alt+9 opens Git. The Log tab shows the history (Fig. 1.20).

Screenshot

Commit: selected files, message, diff; no credentials

Figure 1.19. Preparing a commit in PyCharm

Screenshot

Git > Log: main branch, three meaningful commits

Figure 1.20. Project change history

GitHub is an optional way to submit your work. First check that the repository contains no passwords, tokens, or personal files. Share Project on GitHub creates a remote repository; push sends commits, and clone creates a local copy of the history and working files. A public repository is accessible to other users. Local submission does not require a GitHub account.

Reproducing a project and common problems

For this assignment, a project is reproducible if another student can create a new environment, install the specified dependencies, and obtain the expected result. The README must include the Python version, how to create the environment, the launch command, an example of arguments, and a reference result. A screenshot demonstrates only one run and does not replace source code.

Table 1.3. Diagnosing the development environment

Symptom	Check and action
python is not found	New terminal; where.exe python; Python manager
Activation does not run	Call .venv/Scripts/python.exe directly
A package is “not found”	sys.executable; python -m pip --version
IDE and terminal produce different results	Compare interpreters and working directories
Encoding error in an old console	UTF-8; if needed, python -X utf8 main.py
Git shows .venv	Check .gitignore before the first git add

In Python 3.14, do not assume that every redirected stream has the same encoding across all operating systems. Save code in UTF-8 and check the terminal mode. PYTHONUTF8=1 or -X utf8 enables UTF-8 mode for the process, but does not fix missing font glyphs. Do not replace Ukrainian strings with garbled text to conceal a display problem.

Tip

The initial goal is to explain which Python executes the file, where it gets its packages, and which files went into the commit. Clicking buttons quickly does not replace understanding these three relationships.