Refactor version retrieval in setup.py to read from __init__.py

release/setup.py

@@ -24,14 +24,30 @@
 from many other contributors within Google.
 """
 
+import re
 import sys
 from datetime import date
+from pathlib import Path
 
 from setuptools import find_packages, setup
 from setuptools.command.install import install
 from setuptools.dist import Distribution
 
-CUR_VERSION = "0.7.6"
+
+def read_version():
+    """Return the package version from tensorflow_quantum/__init__.py."""
+    init_path = (Path(__file__).parent.parent / "tensorflow_quantum" /
+                 "__init__.py")
+    init_text = init_path.read_text(encoding="utf-8")
+
+    match = re.search(r'__version__\s*=\s*[\'"]([^\'"]+)[\'"]', init_text)
+    if not match:
+        raise RuntimeError(
+            "Cannot find __version__ in tensorflow_quantum/__init__.py")
+    return match.group(1)
+
+
+CUR_VERSION = read_version()
 
 DOCLINES = __doc__.split("\n")