diff --git a/swh/provenance/tests/data/generate_repo.py b/swh/provenance/tests/data/generate_repo.py
new file mode 100644
index 0000000..2119709
--- /dev/null
+++ b/swh/provenance/tests/data/generate_repo.py
@@ -0,0 +1,101 @@
+import os
+import pathlib
+import shutil
+from subprocess import PIPE, check_call, check_output
+
+import click
+import yaml
+
+
+def clean_wd():
+    _, dirnames, filenames = next(os.walk("."))
+    for d in dirnames:
+        if not d.startswith(".git"):
+            shutil.rmtree(d)
+    for f in filenames:
+        if not f.startswith(".git"):
+            os.unlink(f)
+
+
+def print_ids():
+    revid = check_output(["git", "rev-parse", "HEAD"]).decode().strip()
+    ts, msg = (
+        check_output(["git", "log", "-1", '--format="%at %s"'])
+        .decode()
+        .strip()[1:-1]
+        .split()
+    )
+    print(f"{ts}.0 {revid} {msg}")
+    print(f"{msg:<5} | {'':>5} | {'':>20} | R {revid} | {ts}.0")
+
+    for currentpath, dirnames, filenames in os.walk("."):
+        if currentpath == ".":
+            output = check_output(["git", "cat-file", "-p", "HEAD"]).decode()
+            dirhash = output.splitlines()[0].split()[1]
+        else:
+            currentpath = currentpath[2:]
+            output = check_output(["git", "ls-tree", "HEAD", currentpath]).decode()
+            dirhash = output.split()[2]
+
+        print(f"{'':>5} | {'':>5} | {currentpath:<20} | D {dirhash} | 0.0")
+        for fname in filenames:
+            fname = os.path.join(currentpath, fname)
+            output = check_output(["git", "ls-tree", "HEAD", fname]).decode()
+            fhash = output.split()[2]
+            print(f"{'':>5} | {'':>5} | {fname:<20} | C {fhash} | 0.0")
+
+        if ".git" in dirnames:
+            dirnames.remove(".git")
+
+
+def generate_repo(repo_desc, output_dir):
+    check_call(["git", "init", output_dir], stdout=PIPE, stderr=PIPE)
+    os.chdir(output_dir)
+    os.environ.update(
+        {
+            "GIT_AUTHOR_NAME": "SWH",
+            "GIT_AUTHOR_EMAIL": "contact@softwareheritage.org",
+            "GIT_COMMITTER_NAME": "SWH",
+            "GIT_COMMITTER_EMAIL": "contact@softwareheritage.org",
+        }
+    )
+
+    for rev_d in repo_desc:
+        clean_wd()
+        for path, content in rev_d["content"].items():
+            p = pathlib.Path(path)
+            p.parent.mkdir(parents=True, exist_ok=True)
+            p.write_text(content)
+        os.environ.update(
+            {
+                "GIT_AUTHOR_DATE": str(rev_d["date"]),
+                "GIT_COMMITTER_DATE": str(rev_d["date"]),
+            }
+        )
+        check_call(["git", "add", "."], stdout=PIPE)
+        check_call(
+            [
+                "git",
+                "commit",
+                "--all",
+                "-m",
+                rev_d["msg"],
+            ],
+            stdout=PIPE,
+        )
+        print_ids()
+
+
+@click.command(name="generate-repo")
+@click.argument("input-file")
+@click.argument("output-dir")
+@click.option("-C", "--clean-output/--no-clean-output", default=False)
+def main(input_file, output_dir, clean_output):
+    repo_desc = yaml.load(open(input_file))
+    if clean_output:
+        shutil.rmtree(output_dir)
+    generate_repo(repo_desc, output_dir)
+
+
+if __name__ == "__main__":
+    main()