GNU bug report logs - #51257
grep --ignore-case --color does not always color the matches

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From: Tomasz Dziendzielski <tomasz.dziendzielski@HIDDEN>
Subject: grep --ignore-case --color does not always color the matches
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Hello,
I did some investigation and it seems the problem with '\a' is not that the output is not colored but that it's printed at all while it should not be. It's being printed even when re_search in EGexecute doesn't return a match. As a result the for loop in print_line_middle is not being run - this means the 'a' output that you see is not from the matched string but from the rest of the line. To fix this I suggest to return NULL from print_line_middle if 'b' variable equals NULL - which means the loop was not executed.

I'm sending the patch with the fix in the attachment.

Best regards,
Tomasz Dziendzielski
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    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
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    <div dir="auto">
      <div class="gmail_quote" dir="auto">
        <div dir="ltr" class="gmail_attr">Hello,</div>
        <div dir="ltr" class="gmail_attr">I did some investigation and
          it seems the problem with '\a' is not that the output is not
          colored but that it's printed at all while it should not be.
          It's being printed even when re_search in EGexecute doesn't
          return a match. As a result the for loop in print_line_middle
          is not being run - this means the 'a' output that you see is
          not from the matched string but from the rest of the line. To
          fix this I suggest to return NULL from print_line_middle if
          'b' variable equals NULL - which means the loop was not
          executed.</div>
        <div dir="ltr" class="gmail_attr"><br>
        </div>
        <div dir="ltr" class="gmail_attr">I'm sending the patch with the
          fix in the attachment.</div>
        <div dir="ltr" class="gmail_attr"><br>
        </div>
        <div dir="ltr" class="gmail_attr">Best regards,</div>
        <div dir="ltr" class="gmail_attr">Tomasz Dziendzielski</div>
      </div>
    </div>
  </body>
</html>
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