[newlib-cygwin] makedocbook: Fix false report of unhandled texinfo command

[Jon TURNEY <jturney@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=c03f0c306244bf73239cb1a318a175682f504dc2

commit c03f0c306244bf73239cb1a318a175682f504dc2
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Sat Oct 29 16:43:50 2022 +0100

    makedocbook: Fix false report of unhandled texinfo command
    
    During 'make man', makedocbook falsely reports "texinfo command
    '@modifier' remains in output" while processing the setlocal(3) manpage,
    which contains that literal string.
    
    Move the check for unrecognized texinfo commands to before processing
    '@@' (an escaped '@') in the texinfo source, and teach it to ignore
    them.
    
    Improve that check slightly, so it catches non-alphabetic texinfo
    commands, of which there are few.
    
    Now we don't have false positives, we can make unrecognized texinfo
    commands fatal to manpage generation, rather than leaving them verbatim
    in the generated manpage.

Diff:
---
 newlib/doc/makedocbook.py | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/newlib/doc/makedocbook.py b/newlib/doc/makedocbook.py
index 4de20ef92..9c5615f22 100755
--- a/newlib/doc/makedocbook.py
+++ b/newlib/doc/makedocbook.py
@@ -450,9 +450,6 @@ command_dispatch_dict = {
 def line_markup_convert(p):
     s = p
 
-    # process the texinfo escape for an @
-    s = s.replace('@@', '@')
-
     # escape characters not allowed in XML
     s = s.replace('&', '&amp;')
     s = s.replace('<', '&lt;')
@@ -482,6 +479,14 @@ def line_markup_convert(p):
     # very hacky way of dealing with @* to force a newline
     s = s.replace('@*', '</para><para>')
 
+    # fail if there are unhandled texinfo commands
+    match = re.search(r'(?<!@)@[^@\s]+', s)
+    if match:
+        sys.exit("texinfo command '%s' remains in output" % match.group(0))
+
+    # process the texinfo escape for an @
+    s = s.replace('@@', '@')
+
     if (verbose > 3) and (s != p):
         print('%s-> line_markup_convert ->\n%s' % (p, s), file=sys.stderr)
 
@@ -823,10 +828,6 @@ def main(file):
 
     print(s)
 
-    # warn about texinfo commands which didn't get processed
-    match = re.search(r'@[a-z*]+', s)
-    if match:
-        print('texinfo command %s remains in output' % match.group(), file=sys.stderr)
 
 #
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