doc: clarify "config --bool" behaviour with empty string

`git config --bool xxx.yyy` returns `true` for `[xxx]yyy` but `false` for `[xxx]yyy=` or `[xxx]yyy=""`. This is tested in t1300-repo-config.sh since 09bc098c2. Signed-off-by: Andreas Heiduk <asheiduk@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Andreas Heiduk committed Aug 15, 2017 at 00:12 UTC 7f0a02be2f2712f66daa730e389f45e3e96f1edd
2 files changed +7 -6
Documentation/config.txt
+5 -5
@@ -133,15 +133,15 @@ boolean::
133 synonyms are accepted for 'true' and 'false'; these are all
134 case-insensitive.
135
136 - true;; Boolean true can be spelled as `yes`, `on`, `true`,
137 - or `1`. Also, a variable defined without `= <value>`
136 + true;; Boolean true literals are `yes`, `on`, `true`,
137 + and `1`. Also, a variable defined without `= <value>`
138 is taken as true.
139
140 - false;; Boolean false can be spelled as `no`, `off`,
141 - `false`, or `0`.
140 + false;; Boolean false literals are `no`, `off`, `false`,
141 + `0` and the empty string.
142 +
143 When converting value to the canonical form using `--bool` type
144 -specifier; 'git config' will ensure that the output is "true" or
144 +specifier, 'git config' will ensure that the output is "true" or
145 "false" (spelled in lowercase).
146
147 integer::
Documentation/git.txt
+2 -1
@@ -571,7 +571,8 @@ example the following invocations are equivalent:
571 Note that omitting the `=` in `git -c foo.bar ...` is allowed and sets
572 `foo.bar` to the boolean true value (just like `[foo]bar` would in a
573 config file). Including the equals but with an empty value (like `git -c
574 -foo.bar= ...`) sets `foo.bar` to the empty string.
574 +foo.bar= ...`) sets `foo.bar` to the empty string which ` git config
575 +--bool` will convert to `false`.
576
577 --exec-path[=<path>]::
578 Path to wherever your core Git programs are installed.