bpo-35416: fix potential resource warnings in distutils (GH-10918)

Lib/distutils/command/bdist_rpm.py

@@ -537,7 +537,8 @@ class bdist_rpm(Command):
                     '',
                     '%' + rpm_opt,])
                 if val:
-                    spec_file.extend(open(val, 'r').read().split('\n'))
+                    with open(val) as f:
+                        spec_file.extend(f.read().split('\n'))
                 else:
                     spec_file.append(default)
 

Lib/distutils/command/bdist_wininst.py

@@ -247,47 +247,49 @@ class bdist_wininst(Command):
         self.announce("creating %s" % installer_name)
 
         if bitmap:
-            bitmapdata = open(bitmap, "rb").read()
+            with open(bitmap, "rb") as f:
+                bitmapdata = f.read()
             bitmaplen = len(bitmapdata)
         else:
             bitmaplen = 0
 
-        file = open(installer_name, "wb")
-        file.write(self.get_exe_bytes())
-        if bitmap:
-            file.write(bitmapdata)
+        with open(installer_name, "wb") as file:
+            file.write(self.get_exe_bytes())
+            if bitmap:
+                file.write(bitmapdata)
 
-        # Convert cfgdata from unicode to ascii, mbcs encoded
-        if isinstance(cfgdata, str):
-            cfgdata = cfgdata.encode("mbcs")
+            # Convert cfgdata from unicode to ascii, mbcs encoded
+            if isinstance(cfgdata, str):
+                cfgdata = cfgdata.encode("mbcs")
 
-        # Append the pre-install script
-        cfgdata = cfgdata + b"\0"
-        if self.pre_install_script:
-            # We need to normalize newlines, so we open in text mode and
-            # convert back to bytes. "latin-1" simply avoids any possible
-            # failures.
-            with open(self.pre_install_script, "r",
-                encoding="latin-1") as script:
-                script_data = script.read().encode("latin-1")
-            cfgdata = cfgdata + script_data + b"\n\0"
-        else:
-            # empty pre-install script
+            # Append the pre-install script
             cfgdata = cfgdata + b"\0"
-        file.write(cfgdata)
+            if self.pre_install_script:
+                # We need to normalize newlines, so we open in text mode and
+                # convert back to bytes. "latin-1" simply avoids any possible
+                # failures.
+                with open(self.pre_install_script, "r",
+                    encoding="latin-1") as script:
+                    script_data = script.read().encode("latin-1")
+                cfgdata = cfgdata + script_data + b"\n\0"
+            else:
+                # empty pre-install script
+                cfgdata = cfgdata + b"\0"
+            file.write(cfgdata)
 
-        # The 'magic number' 0x1234567B is used to make sure that the
-        # binary layout of 'cfgdata' is what the wininst.exe binary
-        # expects.  If the layout changes, increment that number, make
-        # the corresponding changes to the wininst.exe sources, and
-        # recompile them.
-        header = struct.pack("<iii",
-                             0x1234567B,       # tag
-                             len(cfgdata),     # length
-                             bitmaplen,        # number of bytes in bitmap
-                             )
-        file.write(header)
-        file.write(open(arcname, "rb").read())
+            # The 'magic number' 0x1234567B is used to make sure that the
+            # binary layout of 'cfgdata' is what the wininst.exe binary
+            # expects.  If the layout changes, increment that number, make
+            # the corresponding changes to the wininst.exe sources, and
+            # recompile them.
+            header = struct.pack("<iii",
+                                0x1234567B,       # tag
+                                len(cfgdata),     # length
+                                bitmaplen,        # number of bytes in bitmap
+                                )
+            file.write(header)
+            with open(arcname, "rb") as f:
+                file.write(f.read())
 
     def get_installer_filename(self, fullname):
         # Factored out to allow overriding in subclasses

Lib/distutils/command/upload.py

@@ -125,8 +125,9 @@ class upload(PyPIRCCommand):
         data['comment'] = ''
 
         if self.sign:
-            data['gpg_signature'] = (os.path.basename(filename) + ".asc",
-                                     open(filename+".asc", "rb").read())
+            with open(filename + ".asc", "rb") as f:
+                data['gpg_signature'] = (os.path.basename(filename) + ".asc",
+                                         f.read())
 
         # set up the authentication
         user_pass = (self.username + ":" + self.password).encode('ascii')

Misc/NEWS.d/next/Library/2018-12-05-09-55-05.bpo-35416.XALKZG.rst

@@ -0,0 +1 @@
+Fix potential resource warnings in distutils. Patch by Mickaël Schoentgen.