PATCH: test of improved backslash quoting

[Peter Stephenson <pws@csr.com>]

This tests the code I added to improved the output of expansion for
invalid or unprintable characters.  As I implied, but possibly didn't
make entirely clear, this affects any case where backslash quoting is
added, including the parameter (q) flag.  I've expanded the
documentation for this.

Note that removal of $'...' quotes is not currently well handled: this
applies both to the (Q) parameter flag and to completion, where already
added $'\...' quoting isn't properly parsed for further handling.  This
is part of the hairy patch I've been trying to do to improve completion
with nested quotes; however, the (Q) part is useful separately and a bit
more tractable, so I'll try and drag it out since it's likely to be
several orders of magnitude quicker than trying to complete the full
patch.

Index: Doc/Zsh/expn.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/expn.yo,v
retrieving revision 1.80
diff -u -r1.80 expn.yo
--- Doc/Zsh/expn.yo	27 Jul 2007 21:51:32 -0000	1.80
+++ Doc/Zsh/expn.yo	22 Aug 2007 10:30:45 -0000
@@ -792,10 +792,14 @@
 tt(${(P)${foo}}), and tt(${(P)$(echo bar)}) will be expanded to `tt(baz)'.
 )
 item(tt(q))(
-Quote the resulting words with backslashes. If this flag is given
+Quote the resulting words with backslashes; unprintable or invalid
+characters are quoted using the tt($'\)var(NNN)tt(') form, with separate
+quotes for each octet.  If this flag is given
 twice, the resulting words are quoted in single quotes and if it is
-given three times, the words are quoted in double quotes. If it is
-given four times, the words are quoted in single quotes preceded by a tt($).
+given three times, the words are quoted in double quotes; in these forms
+no special handling of unprintable or invalid characters is attempted.  If
+the flag is given four times, the words are quoted in single quotes
+preceded by a tt($).
 )
 item(tt(Q))(
 Remove one level of quotes from the resulting words.
Index: Test/D07multibyte.ztst
===================================================================
RCS file: /cvsroot/zsh/zsh/Test/D07multibyte.ztst,v
retrieving revision 1.19
diff -u -r1.19 D07multibyte.ztst
--- Test/D07multibyte.ztst	18 Jun 2007 13:25:10 -0000	1.19
+++ Test/D07multibyte.ztst	22 Aug 2007 10:30:45 -0000
@@ -378,3 +378,9 @@
 >ngs200.txt
 >ngs20.txt
 >ngs2.txt
+
+# Not strictly multibyte, but gives us a well-defined locale for testing.
+  foo=$'X\xc0Y\x07Z\x7fT'
+  print -r ${(q)foo}
+0:Backslash-quoting of unprintable/invalid characters uses $'...'
+>X$'\300'Y$'\a'Z$'\177'T


-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070


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