[3.13] GH-134453: Fix subprocess memoryview input handling on POSIX (GH-134949) #142063
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…ythonGH-134949) Fix inconsistent subprocess.Popen.communicate() behavior between Windows and POSIX when using memoryview objects with non-byte elements as input. On POSIX systems, the code was incorrectly comparing bytes written against element count instead of byte count, causing data truncation for large inputs with non-byte element types. Changes: - Cast memoryview inputs to byte view when input is already a memoryview - Fix progress tracking to use len(input_view) instead of len(self._input) - Add comprehensive test coverage for memoryview inputs 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <[email protected]> * old-man-yells-at-ReST * Update 2025-05-30-18-37-44.gh-issue-134453.kxkA-o.rst * assertIsNone review feedback * fix memoryview_nonbytes test to fail without our fix on main, and have a nicer error. Thanks to Peter Bierma @ZeroIntensity for the code review. (cherry picked from commit cc6bc4c) Co-authored-by: Gregory P. Smith <[email protected]>
This was referenced Nov 29, 2025
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Fix inconsistent subprocess.Popen.communicate() behavior between Windows
and POSIX when using memoryview objects with non-byte elements as input.
On POSIX systems, the code was incorrectly comparing bytes written against
element count instead of byte count, causing data truncation for large
inputs with non-byte element types.
Changes:
🤖 Generated with Claude Code
Co-Authored-By: Claude [email protected]
Thanks to Peter Bierma @ZeroIntensity for the code review.
(cherry picked from commit cc6bc4c)
Co-authored-by: Gregory P. Smith [email protected]
subprocess.Popen.communicate()behavior between Windows and Posix on non-byte memoryview input #134453