[3.14] gh-137412: fix default_builtin_hashes values in test_hashlib.py (GH-137413) (#137534)

Co-authored-by: Bénédikt Tran <[email protected]>

Author: miss-islington

Lib/test/test_hashlib.py

@@ -28,24 +28,17 @@
 from http.client import HTTPException
 
 
-default_builtin_hashes = {'md5', 'sha1', 'sha256', 'sha512', 'sha3', 'blake2'}
+default_builtin_hashes = {'md5', 'sha1', 'sha2', 'sha3', 'blake2'}
 # --with-builtin-hashlib-hashes override
 builtin_hashes = sysconfig.get_config_var("PY_BUILTIN_HASHLIB_HASHES")
 if builtin_hashes is None:
     builtin_hashes = default_builtin_hashes
 else:
-    builtin_hashes = {
-        m.strip() for m in builtin_hashes.strip('"').lower().split(",")
-    }
+    builtin_hash_names = builtin_hashes.strip('"').lower().split(",")
+    builtin_hashes = set(map(str.strip, builtin_hash_names))
 
-# hashlib with and without OpenSSL backend for PBKDF2
-# only import builtin_hashlib when all builtin hashes are available.
-# Otherwise import prints noise on stderr
+# Public 'hashlib' module with OpenSSL backend for PBKDF2.
 openssl_hashlib = import_fresh_module('hashlib', fresh=['_hashlib'])
-if builtin_hashes == default_builtin_hashes:
-    builtin_hashlib = import_fresh_module('hashlib', blocked=['_hashlib'])
-else:
-    builtin_hashlib = None
 
 try:
     from _hashlib import HASH, HASHXOF, openssl_md_meth_names, get_fips_mode