[PATCH 1/6] CodingGuidelines: describe "export VAR=VAL" rule

[Junio C Hamano <gitster@pobox.com>]

https://lore.kernel.org/git/201307081121.22769.tboegi@web.de/
resulted in 9968ffff (test-lint: detect 'export FOO=bar',
2013-07-08) to add a rule to t/check-non-portable-shell.pl script to
reject

	export VAR=VAL

and suggest us to instead write it as "export VAR" followed by
"VAR=VAL".  This however was not spelled out in the CodingGuidelines
document.

We may want to re-evaluate the rule since it is from ages ago, but
for now, let's make the written rule and what the automation enforces
consistent.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 Documentation/CodingGuidelines | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines
index 9495df835d..0a39205c48 100644
--- a/Documentation/CodingGuidelines
+++ b/Documentation/CodingGuidelines
@@ -188,6 +188,12 @@ For shell scripts specifically (not exhaustive):
    hopefully nobody starts using "local" before they are reimplemented
    in C ;-)
 
+ - Some versions of shell do not understand "export variable=value",
+   so we write "export variable" and "variable=value" on separae
+   lines.  Note that this was reported in 2013 and the situation might
+   have changed since then.  We'd need to re-evaluate this rule,
+   together with the rule in t/check-non-portable-shell.pl script.
+
  - Use octal escape sequences (e.g. "\302\242"), not hexadecimal (e.g.
    "\xc2\xa2") in printf format strings, since hexadecimal escape
    sequences are not portable.
-- 
2.44.0-501-g19981daefd