pull: improve advice for unconfigured error case

There are several reasons a git-pull invocation might not
have anything marked for merge:

1. We're not on a branch, so there is no branch
configuration.

2. We're on a branch, but there is no configuration for
this branch.

3. We fetched from the configured remote, but the
configured branch to merge didn't get fetched (either
it doesn't exist, or wasn't part of the fetch refspec).

4. We fetched from the non-default remote, but didn't
specify a branch to merge. We can't use the configured
one because it applies to the default remote.

5. We fetched from a specified remote, and a refspec was
given, but it ended up not fetching anything (this is
actually hard to do; if the refspec points to a remote
branch and it doesn't exist, then fetch will fail and
we never make it to this code path. But if you provide
a wildcard refspec like

refs/bogus/*:refs/remotes/origin/*

then you can see this failure).

We have handled (1) and (2) for some time. Recently, commit
a6dbf88 added code to handle case (3).

This patch handles cases (4) and (5), which previously just
fell under other cases, producing a confusing message.

While we're at it, let's rewrap the text for case (3), which
looks terribly ugly as it is.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-pull.sh b/git-pull.sh
index 66d73eb59d0ce880df9fcf2d34ecc3069dab189d..fc78592ae04283db2af633ec080f99c6404ceda7 100755 (executable)
--- a/git-pull.sh
+++ b/git-pull.sh
@@ -90,8 +90,17 @@ error_on_no_merge_candidates () {
 
        curr_branch=${curr_branch#refs/heads/}
        upstream=$(git config "branch.$curr_branch.merge")
+       remote=$(git config "branch.$curr_branch.remote")
 
-       if [ -z "$curr_branch" ]; then
+       if [ $# -gt 1 ]; then
+               echo "There are no candidates for merging in the refs that you just fetched."
+               echo "Generally this means that you provided a wildcard refspec which had no"
+               echo "matches on the remote end."
+       elif [ $# -gt 0 ] && [ "$1" != "$remote" ]; then
+               echo "You asked to pull from the remote '$1', but did not specify"
+               echo "a branch to merge. Because this is not the default configured remote"
+               echo "for your current branch, you must specify a branch on the command line."
+       elif [ -z "$curr_branch" ]; then
                echo "You are not currently on a branch, so I cannot use any"
                echo "'branch.<branchname>.merge' in your configuration file."
                echo "Please specify which branch you want to merge on the command"
@@ -116,9 +125,8 @@ error_on_no_merge_candidates () {
                echo
                echo "See git-config(1) for details."
        else
-               echo "Your configuration specifies to merge the ref"
-               echo "'${upstream#refs/heads/}' from the remote, but no such ref"
-               echo "was fetched."
+               echo "Your configuration specifies to merge the ref '${upstream#refs/heads/}' from the"
+               echo "remote, but no such ref was fetched."
        fi
        exit 1
 }