Subject: 29.1; Underscore in query replace prevents case-matching

From: Spencer Baugh <[email-masked]>
Date: Wed, 16 Aug 2023 17:27:34 -0400

1. emacs -Q
2. (insert "Foo_bar")
3. M-% foo RET quux RET
4. Observe the buffer contains Quux_bar
5. Undo, so the buffer contains Foo_bar again
6. M-% foo_bar RET quux RET
7. Observe the buffer contains quux

Expected behavior:
7. Observe the buffer contains Quux

It seems to me that this would match the docstring better:

  Replacement transfers the case pattern of the old text to the
  new text, if both ‘case-fold-search’ and ‘case-replace’ are
  non-nil and FROM-STRING has no uppercase letters.

In GNU Emacs 29.1 (build 4, x86_64-pc-linux-gnu, X toolkit, cairo
 version 1.15.12, Xaw scroll bars) of 2023-08-08 built on

Repository revision: ea63217c1c85f1ca4f1f22b9c4781167de6cf00d
Repository branch: my-emacs-29
Windowing system distributor 'The X.Org Foundation', version 11.0.12011000
System Description: Rocky Linux 8.8 (Green Obsidian)

Configured using:
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Configured features:
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Load-path shadows:
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Features:
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Memory information:
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