refactor!: restructure and document configuration

shared/home-manager/dotfiles/git.nix

@@ -0,0 +1,91 @@
+{ ... }:
+
+{
+  # Enable GIT.
+  programs.git = {
+    enable = true;
+
+    aliases = {
+      # List aliases
+      aliases = "config --get-regexp alias";
+
+      # List all the contributors with commit amount
+      contributors = "shortlog --summary --numbered";
+
+      # Output verbose info about branches and tags
+      branches = "branch -avv";
+
+      # List all tags
+      tags = "tag -l";
+
+      # Pretty logs
+      plog = "log --graph --decorate --all";
+
+      # Pretty grep
+      gcommit = "log --graph --decorate --grep";
+    };
+
+    extraConfig = {
+      core = {
+        # Set the editor to be used by GIT
+        editor = "nvim";
+
+        # Custom .gitignore
+        excludesfile = "~/.gitignore";
+
+        # Treat trailing whitespaces and spaces before tabs as an error
+        whitespace = "space-before-tab,-indent-with-non-tab,trailing-space";
+      };
+
+      color = {
+        # Use colors in GIT commmands.
+        ui = "auto";
+      };
+
+      commit = {
+        # https://help.github.com/articles/signing-commits-using-gpg/
+        gpgsign = true;
+      };
+
+      tag = {
+        gpgsign = true;
+      };
+
+      difftool = {
+        prompt = true;
+      };
+
+      mergetool = {
+        # https://www.git-scm.com/docs/git-mergetool#Documentation/git-mergetool.txt---no-prompt
+        prompt = false;
+      };
+
+      merge = {
+        # https://git-scm.com/docs/git-merge#_how_conflicts_are_presented
+        conflictstyle = "diff3";
+      };
+
+      push = {
+        # https://stackoverflow.com/questions/21839651/git-what-is-the-difference-between-push-default-matching-and-simple
+        default = "simple";
+
+        # git-push pushes relevant annotated tags when pushing branches out
+        followTags = true;
+      };
+
+      user = {
+        name = "Alexandre Cavalheiro S. Tiago da Silva";
+        email = "contact@thewizard.link";
+        signingkey = "A1D3A2B4E14BD7C0445BB749A5767B54367CFBDF";
+      };
+
+      pull = {
+        ff = "only";
+      };
+
+      init = {
+        defaultBranch = "main";
+      };
+    };
+  };
+}