tree b880fc69ad2e11423b4ea7249447c687b874a801
parent c374e352f78b5391b79d54a55c82539af49befd9
author Ben Wagner <bungeman@chromium.org> 1749047778 -0700
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1749047778 -0700

Current font need not contain part of ActualText

When handling marked content there is currently a check that if the
current font does not have a mapping for any of the code points in an
ActualText then the ActualText is ignored. This check has been in the
code since the initial code drop. This undermines part of the purpose of
ActualText, such as providing the original code points even if there was
no font which represented them.

In addition, it is not clear why this behavior would be wanted. One
possibility is an attempt to reduce phishing where the copied (or
accessible) content is intentionally different from was is drawn on the
page (especially with respect to Unicode confusables). However, this is
generally malicious content which could easily work around such a check
by simply adding mappings in its fonts. Any benefit of ignoring such
ActualText has the downside of incorrectly handling real and intentional
uses like when multiple code points map to a single glyph in a font.

Remove this check and add a test which replaces English words with
Chinese replacements. This test fails before this change as the default
test font does not contain both sets of code points.

Bug: 420508260
Change-Id: I4d82b603e5bda8ed13614e6ba3a4ce0c8f8f0d62
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/132710
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>