1 files changed, 120 insertions, 0 deletions
diff --git a/contrib/git-stats-graph.py b/contrib/git-stats-graph.py
new file mode 100755
index 00000000..7632d566
--- /dev/null
+++ b/contrib/git-stats-graph.py
@@ -0,0 +1,120 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: MIT
+# Copyright (c) 2023 Bence Ferdinandy <bence@ferdinandy.com>
+
+"""
+Create graphs about development statistics of releases.
+"""
+
+from datetime import date
+from subprocess import check_output
+
+from matplotlib import pyplot as plt
+
+
+def git(*args):
+    return check_output(["git"] + list(args)).decode("utf-8").strip()
+
+
+def stats():
+    """
+    Returns statistics from the git repo:
+
+    tags: sorted list of minor version tags (assumes semver)
+          The first element is the hash of the first commit, last element is HEAD.  All
+          the other return values are one shorter as, there's no statistics returned for
+          the first commit.
+    counts: number of commits (between this and the previous release)
+    dates: dates of the releases
+    files: number of files changed (between this and the previous release)
+    inserts: number of lines inserted (between this and the previous release)
+    deletions: number of lines deleted (between this and the previous release)
+    """
+
+    tags = git("tag").split("\n")
+    tags = [t for t in tags if t.split(".")[-1] == "0"]  # drop patch versions
+    tags = sorted(tags, key=lambda x: [int(t) for t in x.split(".")])
+    first_commit = git("rev-list", "--max-parents=0", "HEAD")
+    tags = [first_commit] + tags + ["HEAD"]
+    counts = []
+    dates = []
+    files = []
+    inserts = []
+    deletions = []
+    for i, t in enumerate(tags[:-1]):
+        counts.append(int(git("rev-list", f"{t}..{tags[i+1]}", "--count")))
+        dates.append(
+            date.fromisoformat(git("show", "-s", "--format=%cs", t).split("\n")[-1])
+        )
+        statline = git("diff", "--stat", t, tags[i + 1]).split("\n")[-1]
+        fnum, _, _, ins, _, dels, _ = statline.split()
+        files.append(int(fnum))
+        inserts.append(int(ins))
+        deletions.append(int(dels))
+    return tags, counts, dates, files, inserts, deletions
+
+
+def main(output):
+    tags, counts, dates, files, inserts, deletions = stats()
+
+    fig, (ax1, ax2) = plt.subplots(2, figsize=(8, 11))
+    fig.suptitle("aerc release statistics", fontweight="bold")
+    # commit counts subplot
+    ax1.plot(dates, counts, "o-")
+
+    # alternate placement of text above and below for readability
+    text_y = []
+    for i, t in enumerate(tags[1:]):
+        downpad = 25 if len(t) == 5 else 30
+        p = counts[i] + (-1) ** (i + 1) * 10 - (i + 1) % 2 * downpad
+        if p < 5:
+            p = counts[i] + 10
+        text_y.append(p)
+    for i, t in enumerate(tags[1:]):
+        ax1.text(
+            dates[i],
+            text_y[i],
+            t,
+            horizontalalignment="center",
+            rotation="vertical",
+        )
+    ax1.set_ylabel("# of commits")
+    ax1.set_ylim(bottom=0)
+    ax1.set_title("commits per release")
+
+    # lines added/deleted subplot
+    #
+    ax2.plot(dates, inserts, "o-", label="insertions(+)", color="green")
+    ax2.plot(dates, deletions, "o-.", label="deletions(-)", color="red")
+    ax2.set_ylabel("# of lines")
+    ax2.legend(loc="upper left")
+    ax2.set_ylim(top=max(max(inserts), max(deletions)) + 2000)
+    for i, t in enumerate(tags[1:]):
+        ax2.text(
+            dates[i],
+            max(inserts[i], deletions[i]) + 500,
+            t,
+            horizontalalignment="center",
+            rotation="vertical",
+        )
+    ax2.set_xlabel("date")
+    ax2.set_title("insertion/deletions per release")
+    plt.tight_layout()
+    plt.savefig(output, dpi=300)
+
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        "-o",
+        "--output",
+        default="aerc-release-stats.png",
+        help="""
+        Path to output image (defaults to 'aerc-release-stats.png',
+        respects file extensions via matplotlib)
+        """,
+    )
+    args = parser.parse_args()
+    main(args.output)