trace: avoid unnecessary quoting
Trace output which contains arbitrary strings (e.g., the
arguments to commands which we are running) is always passed
through sq_quote_buf(). That function always adds
single-quotes, even if the output consists of vanilla
characters. This can make the output a bit hard to read.
Let's avoid the quoting if there are no characters which a
shell would interpret. Trace output doesn't necessarily need
to be shell-compatible, but:
- the shell language is a good ballpark for what humans
consider readable (well, humans versed in command line
tools)
- the run_command bits can be cut-and-pasted to a shell,
and we'll keep that property
- it covers any cases which would make the output
visually ambiguous (e.g., embedded whitespace or quotes)
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>