2 files changed, 121 insertions, 0 deletions
diff --git a/packages/git-blame-stats/default.nix b/packages/git-blame-stats/default.nix
new file mode 100644
index 0000000..aab7cfb
--- /dev/null
+++ b/packages/git-blame-stats/default.nix
@@ -0,0 +1,26 @@
+{ lib, python3, stdenvNoCC, pkgs }:
+
+stdenvNoCC.mkDerivation rec {
+  pname = "git-blame-stats";
+  src = ./git-blame-stats.py;
+  version = "0.1.1";
+
+  nativeBuildInputs = with pkgs; [ python3 ];
+  propagatedBuildInputs = with pkgs; [ python3 ];
+
+  dontUnpack = true;
+  dontBuild = true;
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp $src $out/bin/${pname}
+  '';
+
+
+  meta = with pkgs.lib; {
+    description = "CLI to reports git blame statistics per author.";
+    license = licenses.mit;
+    platforms = platforms.unix;
+    maintainers = [ ];
+  };
+}
diff --git a/packages/git-blame-stats/git-blame-stats.py b/packages/git-blame-stats/git-blame-stats.py
new file mode 100755
index 0000000..3cc4f4a
--- /dev/null
+++ b/packages/git-blame-stats/git-blame-stats.py
@@ -0,0 +1,95 @@
+#!/usr/bin/env python3
+
+import argparse
+import subprocess
+from typing import Any
+
+
+parser = argparse.ArgumentParser()
+parser.add_argument(
+    "rev", metavar="revision", type=str, help="the revision", default="HEAD", nargs="?"
+)
+args = parser.parse_args()
+
+authors: dict[str, Any] = dict()
+max_lenght_author = 0
+max_lenght_email = 0
+
+
+def get_files(rev):
+    """Returns a list of files for the repository, at the given path, for the given revision."""
+    tree = subprocess.run(
+        ["git", "ls-tree", "--name-only", "-r", rev],
+        capture_output=True,
+        check=True,
+        encoding="utf-8",
+    )
+    return tree.stdout.splitlines()
+
+
+def line_info(filename, rev):
+    """Generates a set of commit blocks using `git blame` for a file.
+
+    Each block corresponds to the information about a single line of code."""
+    blame = subprocess.run(
+        ["git", "blame", "-w", "--line-porcelain", rev, "--", filename],
+        capture_output=True,
+        encoding="utf-8",
+        check=True,
+    )
+    block = []
+    for line in blame.stdout.splitlines():
+        block.append(line)
+        if line.startswith("\t"):
+            yield block
+            block = []
+
+
+files = get_files(args.rev)
+
+for filename in files:
+    try:
+        for block in line_info(filename.rstrip(), args.rev):
+            author = ""
+            author_email = ""
+            commit = ""
+            skip = False
+            for i, val in enumerate(block):
+                if i == 0:
+                    commit = val.split()[0]
+                    continue
+                if val.startswith("author "):
+                    author = " ".join(val.split()[1:])
+                    continue
+                if val.startswith("author-mail"):
+                    author_email = " ".join(val.split()[1:])
+                    continue
+                if val.startswith("\t") and val == "\t":
+                    skip = True
+            if skip:
+                continue
+            if authors.get(author, None) is None:
+                authors[author] = {
+                    "email": author_email,
+                    "commits": set(),
+                    "files": set(),
+                    "lines": 0,
+                }
+            authors[author]["commits"].add(commit)
+            authors[author]["files"].add(filename)
+            authors[author]["lines"] += 1
+            if len(author) > max_lenght_author:
+                max_lenght_author = len(author)
+            if len(author_email) > max_lenght_email:
+                max_lenght_email = len(author_email)
+    except Exception:
+        continue
+
+for author, stats in authors.items():
+    email = stats["email"]
+    lines = stats["lines"]
+    commits = len(stats["commits"])
+    files = len(stats["files"])
+    print(
+        f"{author:{max_lenght_author}} {email:{max_lenght_email}} {lines:6} {commits:6} {files:6}"
+    )