Issue #8833: tarfile created hard link entries with a size

field != 0 by mistake. The associated testcase did not
expose this bug because it was broken too.

Lib/tarfile.py

@@ -1884,7 +1884,7 @@ class TarFile(object):
         tarinfo.mode = stmd
         tarinfo.uid = statres.st_uid
         tarinfo.gid = statres.st_gid
-        if stat.S_ISREG(stmd):
+        if type == REGTYPE:
             tarinfo.size = statres.st_size
         else:
             tarinfo.size = 0L

Lib/test/test_tarfile.py

@@ -662,10 +662,14 @@ class WriteTest(WriteTestBase):
         if hasattr(os, "link"):
             link = os.path.join(TEMPDIR, "link")
             target = os.path.join(TEMPDIR, "link_target")
-            open(target, "wb").close()
+            fobj = open(target, "wb")
+            fobj.write("aaa")
+            fobj.close()
             os.link(target, link)
             try:
                 tar = tarfile.open(tmpname, self.mode)
+                # Record the link target in the inodes list.
+                tar.gettarinfo(target)
                 tarinfo = tar.gettarinfo(link)
                 self.assertEqual(tarinfo.size, 0)
             finally:

Misc/NEWS

@@ -46,6 +46,9 @@ C-API
 Library
 -------
 
+- Issue #8833: tarfile created hard link entries with a size field != 0 by
+  mistake.
+
 - Issue #1368247: set_charset (and therefore MIMEText) now automatically
   encodes a unicode _payload to the output_charset.