Re: [PATCH v3 1/4] mergetool--lib: simplify command expressions

David Aguilar [off-list ref] writes:

Update variable assignments to always use $(command "$arg")
in their RHS instead of "$(command "$arg")" as the latter
is harder to read.  Make get_merge_tool_cmd() simpler by
avoiding "echo" and $(command) substitutions completely.

Signed-off-by: David Aguilar <redacted>
---
This is a replacement patch for what's currently in pu to
fix the empty "test -z" expression.

Thanks.

I think I already pushed out what I locally amended; will double
check.