bug#2397: 23.0.90; grep no longer highlights the match

["Drew Adams" <drew.adams@oracle.com>]

> >> Also please eval `M-x grep RET set RET'
> >
> > Sorry, I don't understand. That does nothing; it just exits 
> > with no matches found - there are no file arguments specified.
> > And in which directory? With which `grep' switches? I don't follow.
> >
> >> and show the value of the environment variable `TERM'.
> 
> `M-x grep RET set RET' should print a list of grep environment
> variables in a Unix-like shell instead of running a grep command.

grep -nH -e set
Grep finished with no matches found at Sun Feb 22 14:17:17

(Likewise, without the switches.)

This is in GNU Emacs 23.0.90.1 (i386-mingw-nt5.1.2600)
 of 2009-02-01 on SOFT-MJASON
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4)',
after loading the two files I cited: cygwin-mount.el and setup-cygwin.el.

And `grep --help' does not mention `set'. This is all it says:

------8<-------------------------
Usage: grep [OPTION]... PATTERN [FILE] ...
Search for PATTERN in each FILE or standard input.
Example: grep -i 'hello world' menu.h main.c

Regexp selection and interpretation:
  -E, --extended-regexp     PATTERN is an extended regular expression
  -F, --fixed-strings       PATTERN is a set of newline-separated strings
  -G, --basic-regexp        PATTERN is a basic regular expression
  -P, --perl-regexp         PATTERN is a Perl regular expression
  -e, --regexp=PATTERN      use PATTERN as a regular expression
  -f, --file=FILE           obtain PATTERN from FILE
  -i, --ignore-case         ignore case distinctions
  -w, --word-regexp         force PATTERN to match only whole words
  -x, --line-regexp         force PATTERN to match only whole lines
  -z, --null-data           a data line ends in 0 byte, not newline

Miscellaneous:
  -s, --no-messages         suppress error messages
  -v, --invert-match        select non-matching lines
  -V, --version             print version information and exit
      --help                display this help and exit
      --mmap                use memory-mapped input if possible

Output control:
  -m, --max-count=NUM       stop after NUM matches
  -b, --byte-offset         print the byte offset with output lines
  -n, --line-number         print line number with output lines
      --line-buffered       flush output on every line
  -H, --with-filename       print the filename for each match
  -h, --no-filename         suppress the prefixing filename on output
      --label=LABEL         print LABEL as filename for standard input
  -o, --only-matching       show only the part of a line matching PATTERN
  -q, --quiet, --silent     suppress all normal output
      --binary-files=TYPE   assume that binary files are TYPE
                            TYPE is 'binary', 'text', or 'without-match'
  -a, --text                equivalent to --binary-files=text
  -I                        equivalent to --binary-files=without-match
  -d, --directories=ACTION  how to handle directories
                            ACTION is 'read', 'recurse', or 'skip'
  -D, --devices=ACTION      how to handle devices, FIFOs and sockets
                            ACTION is 'read' or 'skip'
  -R, -r, --recursive       equivalent to --directories=recurse
      --include=PATTERN     files that match PATTERN will be examined
      --exclude=PATTERN     files that match PATTERN will be skipped.
      --exclude-from=FILE   files that match PATTERN in FILE will be skipped.
  -L, --files-without-match only print FILE names containing no match
  -l, --files-with-matches  only print FILE names containing matches
  -c, --count               only print a count of matching lines per FILE
  -Z, --null                print 0 byte after FILE name

Context control:
  -B, --before-context=NUM  print NUM lines of leading context
  -A, --after-context=NUM   print NUM lines of trailing context
  -C, --context=NUM         print NUM lines of output context
  -NUM                      same as --context=NUM
      --color[=WHEN],
      --colour[=WHEN]       use markers to distinguish the matching string
                            WHEN may be `always', `never' or `auto'.
  -U, --binary              do not strip CR characters at EOL (MSDOS)
  -u, --unix-byte-offsets   report offsets as if CRs were not there (MSDOS)

`egrep' means `grep -E'.  `fgrep' means `grep -F'.
With no FILE, or when FILE is -, read standard input.  If less than
two FILEs given, assume -h.  Exit status is 0 if match, 1 if no match,
and 2 if trouble.

Report bugs to <bug-grep@gnu.org>.
------8<-------------------------

> But it seems your shell where grep runs is not bash.  Perhaps
> this is the cause of your problems.

grep -nH -e echo $SHELL
Binary file C:/cygwin/bin/bash.exe matches

Looks like bash to me. And it's always acted like bash, AFAICT.
 
> > M-: (getenv "TERM) gives "dumb", both in emacs -Q and in my 
> > own environment (i.e., after loading the cywin libraries I
> > mentioned).
> 
> It is normal that (getenv "TERM") gives "dumb".  More important
> is to see the value of "TERM" in the grep environment.  Could
> you try some other command instead of "grep" to see the value
> of "TERM" after running the `grep' command?  For example,
> `M-x grep RET echo $TERM RET'.

That gives this:

grep -nH -e echo $TERM
grep: emacs-grep: No such file or directory