[build] Extract package version from __init__.py (#288)

Author: harshitpawar64

setup.cfg

@@ -1,7 +1,5 @@
 [metadata]
 name = fast_llm
-# TODO: Take from __init__.py instead?
-version = 0.2.0
 
 [options]
 packages = find_namespace:

setup.py

@@ -1,4 +1,6 @@
 import sys
+import re
+import pathlib
 
 try:
     import pybind11
@@ -16,6 +18,14 @@
     print(f"Error: setuptools version {_SETUPTOOLS_MIN_VERSION} " "or greater is required")
     sys.exit(1)
 
+def get_version():
+    """Read version from fast_llm/__init__.py"""
+    init_file = pathlib.Path(__file__).parent.joinpath("fast_llm", "__init__.py").read_text()
+    version_match = re.search(r"^__version__ = ['\"]([^'\"]*)['\"]", init_file, re.M)
+    if version_match:
+        return version_match.group(1)
+    raise RuntimeError("Unable to find version string in fast_llm/__init__.py")
+
 cpp_extension = setuptools.Extension(
     "fast_llm.csrc.data",
     sources=["fast_llm/csrc/data.cpp"],
@@ -27,4 +37,5 @@
 
 setuptools.setup(
     ext_modules=[cpp_extension],
+    version=get_version(),
 )