Use NumPy methodology for generating version

meson.build

@@ -2,7 +2,9 @@
 project(
     'pandas',
     'c', 'cpp', 'cython',
-    version: run_command(['generate_version.py', '--print'], check: true).stdout().strip(),
+    version: run_command(
+        ['python', 'pandas/_build_utils/gitversion.py'],
+        check: true).stdout().strip(),
     license: 'BSD-3',
     meson_version: '>=1.2.1',
     default_options: [
@@ -15,8 +17,6 @@ project(
 fs = import('fs')
 py = import('python').find_installation(pure: false)
 tempita = files('generate_pxi.py')
-versioneer = files('generate_version.py')
-
 
 add_project_arguments('-DNPY_NO_DEPRECATED_API=0', language : 'c')
 add_project_arguments('-DNPY_NO_DEPRECATED_API=0', language : 'cpp')
@@ -27,23 +27,6 @@ add_project_arguments('-DNPY_NO_DEPRECATED_API=0', language : 'cpp')
 add_project_arguments('-DNPY_TARGET_VERSION=NPY_1_21_API_VERSION', language : 'c')
 add_project_arguments('-DNPY_TARGET_VERSION=NPY_1_21_API_VERSION', language : 'cpp')
 
-
-if fs.exists('_version_meson.py')
-    py.install_sources('_version_meson.py', subdir: 'pandas')
-else
-    custom_target('write_version_file',
-        output: '_version_meson.py',
-        command: [
-            py, versioneer, '-o', '@OUTPUT@'
-        ],
-        build_by_default: true,
-        build_always_stale: true,
-        install: true,
-        install_dir: py.get_install_dir() / 'pandas'
-    )
-    meson.add_dist_script(py, versioneer, '-o', '_version_meson.py')
-endif
-
 # Needed by pandas.test() when it looks for the pytest ini options
 py.install_sources(
     'pyproject.toml',

pandas/__init__.py

@@ -171,22 +171,7 @@
 
 from pandas.util._tester import test
 
-# use the closest tagged version if possible
-_built_with_meson = False
-try:
-    from pandas._version_meson import (  # pyright: ignore [reportMissingImports]
-        __version__,
-        __git_version__,
-    )
-
-    _built_with_meson = True
-except ImportError:
-    from pandas._version import get_versions
-
-    v = get_versions()
-    __version__ = v.get("closest-tag", v["version"])
-    __git_version__ = v.get("full-revisionid")
-    del get_versions, v
+# If a version with git hash was stored, use that instead
 
 
 # module level doc-string

pandas/_build_utils/gitversion.py

@@ -0,0 +1,90 @@
+# This file is vendored from NumPy. See NUMPY_LICENSE.txt
+
+#!/usr/bin/env python3
+import os
+import textwrap
+
+
+def init_version():
+    init = os.path.join(os.path.dirname(__file__), "../../pyproject.toml")
+    with open(init) as fid:
+        data = fid.readlines()
+
+    version_line = next(line for line in data if line.startswith("version ="))
+
+    version = version_line.strip().split(" = ")[1]
+    version = version.replace('"', "").replace("'", "")
+
+    return version
+
+
+def git_version(version):
+    # Append last commit date and hash to dev version information,
+    # if available
+
+    import os.path
+    import subprocess
+
+    git_hash = ""
+    try:
+        p = subprocess.Popen(
+            ["git", "log", "-1", '--format="%H %aI"'],
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            cwd=os.path.dirname(__file__),
+        )
+    except FileNotFoundError:
+        pass
+    else:
+        out, err = p.communicate()
+        if p.returncode == 0:
+            git_hash, git_date = (
+                out.decode("utf-8")
+                .strip()
+                .replace('"', "")
+                .split("T")[0]
+                .replace("-", "")
+                .split()
+            )
+
+            # Only attach git tag to development versions
+            if "dev" in version:
+                version += f"+git{git_date}.{git_hash[:7]}"
+
+    return version, git_hash
+
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--write", help="Save version to this file")
+    parser.add_argument(
+        "--meson-dist",
+        help="Output path is relative to MESON_DIST_ROOT",
+        action="store_true",
+    )
+    args = parser.parse_args()
+
+    version, git_hash = git_version(init_version())
+
+    template = textwrap.dedent(f"""
+        version = "{version}"
+        __version__ = version
+    """)
+
+    if args.write:
+        outfile = args.write
+        if args.meson_dist:
+            outfile = os.path.join(os.environ.get("MESON_DIST_ROOT", ""), outfile)
+
+        # Print human readable output path
+        relpath = os.path.relpath(outfile)
+        if relpath.startswith("."):
+            relpath = outfile
+
+        with open(outfile, "w") as f:
+            print(f"Saving version to {relpath}")
+            f.write(template)
+    else:
+        print(version)