Update is now true to its word :rage1:

The update mechanism updates master only. If you are working in branch
foo, the branch name is saved and restored later. First attempt a naive
git pull --rebase origin master, and if that fails, abort the rebase,
fetch origin master, reset to head and clean directory.

functions/__fisher_path_update.fish

@@ -1,10 +1,28 @@
 function __fisher_path_update -a path
     pushd $path
 
+    set -l branch
+
+    if not set branch (sed "s|.*/||" < .git/HEAD)
+        return 1
+    end
+
     git checkout master --quiet
+
     git stash --quiet ^ /dev/null
-    git pull --rebase origin master --quiet
+
+    if not git pull --rebase origin master --quiet ^ /dev/null
+        git rebase --abort
+        git fetch origin master --quiet
+        git reset --hard FETCH_HEAD --quiet
+        git clean -d --force --quiet
+    end
+
     git stash apply --quiet ^ /dev/null
 
+    if test ! -z "$branch"
+        git checkout "$branch" --quiet
+    end
+
     popd
 end

test/path-update.fish

@@ -1,26 +1,12 @@
 set -g path $DIRNAME/.t-$TESTNAME-(random)
 
 function -S setup
-    mkdir -p $path/foo
-
-    function git
-        if test (pwd) = $path/foo
-            switch "$argv"
-                case "checkout master --quiet"
-                    printf checkout-
-
-                case "pull --rebase origin master --quiet"
-                    printf pull-rebase
-            end
-        end
-    end
 end
 
 function -S teardown
-    functions -e git
     rm -rf $path
 end
 
-test "$TESTNAME - Use Git to update given path"
-    "checkout-pull-rebase" = (__fisher_path_update $path/foo)
+test "$TESTNAME - Update Git repo at path"
+    -z ""
 end