shortlog: warn the user when there is no input

diff --git a/Documentation/git-show-ref.txt b/Documentation/git-show-ref.txt
index 98e294aa869d39575ab32d859ca9fcc3bfcaf789..df17d49b87c260c6f5b3fd75d4aad41b77fcf8c3 100644 (file)
--- a/Documentation/git-show-ref.txt
+++ b/Documentation/git-show-ref.txt
@@ -8,9 +8,10 @@ git-show-ref - List references in a local repository
 SYNOPSIS
 --------
 [verse]
-'git show-ref' [-q|--quiet] [--verify] [-h|--head] [-d|--dereference]
-            [-s|--hash] [--abbrev] [--tags] [--heads] [--] <pattern>...
-'git show-ref' --exclude-existing[=pattern]
+'git show-ref' [-q|--quiet] [--verify] [--head] [-d|--dereference]
+            [-s|--hash[=<n>]] [--abbrev[=<n>]] [--tags]
+            [--heads] [--] <pattern>...
+'git show-ref' --exclude-existing[=<pattern>] < ref-list
 
 DESCRIPTION
 -----------
@@ -29,7 +30,6 @@ the `.git` directory.
 OPTIONS
 -------
 
--h::
 --head::
 
        Show the HEAD reference.
@@ -48,7 +48,7 @@ OPTIONS
        appended.
 
 -s::
---hash::
+--hash[=<n>]::
 
        Only show the SHA1 hash, not the reference name. When combined with
        --dereference the dereferenced tag will still be shown after the SHA1.
@@ -59,11 +59,10 @@ OPTIONS
        Aside from returning an error code of 1, it will also print an error
        message if '--quiet' was not specified.
 
---abbrev::
---abbrev=len::
+--abbrev[=<n>]::
 
        Abbreviate the object name.  When using `--hash`, you do
-       not have to say `--hash --abbrev`; `--hash=len` would do.
+       not have to say `--hash --abbrev`; `--hash=n` would do.
 
 -q::
 --quiet::
@@ -71,10 +70,9 @@ OPTIONS
        Do not print any results to stdout. When combined with '--verify' this
        can be used to silently check if a reference exists.
 
---exclude-existing::
---exclude-existing=pattern::
+--exclude-existing[=<pattern>]::
 
-       Make 'git-show-ref' act as a filter that reads refs from stdin of the
+       Make 'git show-ref' act as a filter that reads refs from stdin of the
        form "^(?:<anything>\s)?<refname>(?:\^\{\})?$" and performs the
        following actions on each:
        (1) strip "^{}" at the end of line if any;
@@ -137,7 +135,7 @@ When using the '--verify' flag, the command requires an exact path:
 
 will only match the exact branch called "master".
 
-If nothing matches, 'git-show-ref' will return an error code of 1,
+If nothing matches, 'git show-ref' will return an error code of 1,
 and in the case of verification, it will show an error message.
 
 For scripting, you can ask it to be quiet with the "--quiet" flag, which