From 4de58250ce5a1fdf6f920ec326bbaaa720ca4f73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9rgio=20M=2E=20Basto?= <sergio@serjux.com>
Date: Tue, 30 Dec 2025 05:47:59 +0000
Subject: [PATCH] (#140) bugfix: Pipes are only done from stdout to stdin

stderr does not belong in pipes

No mixing of wait() and communicate()

Either stdout goes directly to the terminal, or everything is captured

Each process writes to stdout

The next reads from stdin

The terminal or editor handles the rest
---
 patchview/patchview-wrapper | 77 +++++++++++++++++--------------------
 1 file changed, 35 insertions(+), 42 deletions(-)

diff --git a/patchview/patchview-wrapper b/patchview/patchview-wrapper
index 73512b33..989d0fa2 100755
--- a/patchview/patchview-wrapper
+++ b/patchview/patchview-wrapper
@@ -1,7 +1,8 @@
 #!/usr/bin/python3
-# SPDX-License-Identifier: GPL-2.0-or-later
 # -*- coding: utf-8 -*-
 #
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
 # Copyright (C) 2015-2025 Sérgio Basto <sergio@serjux.com>
 #
 # This program is free software; you can redistribute it and/or modify it
@@ -54,60 +55,52 @@ parser = argparse.ArgumentParser()
 parser.add_argument('-v', '--debug',
                     help='writes the commands that will be executed',
                     action='store_true')
-parser.add_argument('git_args', nargs='*', default=[])
+parser.add_argument('tool_args', nargs='*', default=[])
 parser.add_argument('patchview_args', nargs=argparse.REMAINDER)
 args, unknown = parser.parse_known_args()
-largs = vars(args).get("git_args")
-rargs = vars(args).get("patchview_args")
+tool_args = args.tool_args
+patchview_args = args.patchview_args + unknown
+
+pipetoview = tool_cmd.endswith("view")
+if pipetoview:
+    tool_cmd = tool_cmd[:-4]
+    patchview_cmd = ["filterdiff"] + patchview_args
+else:
+    patchview_cmd = ["patchview"] + patchview_args
 
-patchview_cmd = ["patchview"] + rargs + unknown
-pipetoview = False
-if tool_cmd.endswith("view"):
-    # pipeline: first_pipe | second_pipe | editor
-    tool_cmd = tool_cmd[:-4]  # remove "view"
-    patchview_cmd = ["filterdiff"] + rargs + unknown
-    pipetoview = True
-git_cmd = [tool, tool_cmd] + largs
+vcs_cmd = [tool, tool_cmd] + tool_args
+dest_cmd = [editor, "-R", "-"]
 
-p1 = Popen(git_cmd, stdout=PIPE, env=enviro, cwd=workdir)
-p2 = Popen(patchview_cmd, stdin=p1.stdout, stdout=PIPE, env=enviro, cwd=workdir)
+if args.debug:
+    debug_str = "%s | %s" % (" ".join(vcs_cmd), " ".join(patchview_cmd))
+    if pipetoview:
+        debug_str += " | %s" % " ".join(dest_cmd)
+    sys.stderr.buffer.write((debug_str + "\n").encode())
+    sys.stderr.flush()
+
+p1 = Popen(vcs_cmd, stdout=PIPE, env=enviro, cwd=workdir)
+if pipetoview:
+    p2 = Popen(patchview_cmd, stdin=p1.stdout, stdout=PIPE, env=enviro, cwd=workdir)
+else:
+    p2 = Popen(patchview_cmd, stdin=p1.stdout, env=enviro, cwd=workdir)
 
 p1.wait()
-stdout1, stderr1 = p1.communicate()
-if p1.returncode != 0:
+ret1 = p1.returncode
+if ret1 != 0:
+    stdout1, _ = p1.communicate()
     if stdout1:
         sys.stdout.buffer.write(stdout1)
-    if stderr1:
-        sys.stderr.buffer.write(stderr1)
-    sys.exit(p1.returncode)
+    sys.exit(ret1)
 
 p2.wait()
-stdout2, stderr2 = p2.communicate()
-if p2.returncode != 0:
+ret2 = p2.returncode
+if ret2 != 0:
+    stdout2, _ = p2.communicate()
     if stdout2:
         sys.stdout.buffer.write(stdout2)
-    if stderr2:
-        sys.stderr.buffer.write(stderr2)
-    sys.exit(p2.returncode)
+    sys.exit(ret2)
 
 if pipetoview:
-    dest_cmd = [editor, "-R", "-"]
-    p3 = Popen(dest_cmd, stdin=PIPE)
-    if args.debug:
-        debug_str = "%s | %s | %s\n" % (" ".join(git_cmd),
-                                     " ".join(patchview_cmd),
-                                     " ".join(dest_cmd))
-        p3.stdin.write(debug_str.encode())
-        p3.stdin.flush()
-
-    p3.stdin.write(stdout2)
-    p3.stdin.close()
+    p3 = Popen(dest_cmd, stdin=p2.stdout, env=enviro, cwd=workdir)
     p3.wait()
-else:
-    # debug print
-    if args.debug:
-        print("%s | %s" % (" ".join(git_cmd), " ".join(patchview_cmd)))
-        sys.stdout.flush()
-
-    sys.stdout.buffer.write(stdout2)