[BUILTIN] Dotcmd should exit with zero when doing nothing

Tim Allen wrote:

> The POSIX specification for the dot command[1] states:
>
>     EXIT STATUS
>         Returns the value of the last command executed, or a zero exit
>         status if no command is executed.
>
> If an empty file is sourced, then "no command is executed"

I agree.  Looking through "git log --patch src/main.c", though, I find
v0.5.3~42 (Do not clobber exit status in dotcmd., 2005-03-03), which
appears to have been meant to take care of the following case:

        $ cat printstatus.sh
        echo $?
        $ false
        $ . ./printstatus.sh
        1

I wonder if the following on top might help (imitating evalcmd)?

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 4 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 6d02fa9..8a832bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2011-03-10  Jonathan Nieder <jrnieder@gmail.com>
+
+	* Dotcmd should exit with zero when doing nothing.
+
 2011-03-10  Herbert Xu <herbert@gondor.apana.org.au>
 
 	* Fix CTLESC clobbering by read(1).