diff --git a/share/completions/git.fish b/share/completions/git.fish
index 91934ff9a..e4b4ae7f7 100644
--- a/share/completions/git.fish
+++ b/share/completions/git.fish
@@ -2242,15 +2242,13 @@ end
 
 # source git-* commands' autocompletion file if exists
 set -f __fish_git_custom_commands_completion
-for file in $PATHgitdash
-    test ! -x $file
-    and continue
-
-    set -l subcommand (path basename $file)
+for file in (path filter -xZ -- $PATHgitdash | path basename)
     # Already seen this command earlier in $PATH.
-    contains -- $subcommand $__fish_git_custom_commands_completion
+    contains -- $file $__fish_git_custom_commands_completion
     and continue
 
-    complete -c git -f -n "__fish_git_using_command $subcommand" -a "(__fish_git_complete_custom_command $subcommand)"
+    # Running `git foo` ends up running `git-foo`, so we need to ignore the `git-` here.
+    set -l cmd (string replace -r '^git-' '' -- $file)
+    complete -c git -f -n "__fish_git_using_command $cmd" -a "(__fish_git_complete_custom_command $cmd)"
     set -a __fish_git_custom_commands_completion $subcommand
 end
diff --git a/tests/checks/git.fish b/tests/checks/git.fish
index 4fc6f76e4..f5b337a1a 100644
--- a/tests/checks/git.fish
+++ b/tests/checks/git.fish
@@ -33,6 +33,19 @@ git init >/dev/null 2>&1
 # First set up a test alias - *before loading the completions*
 git config --local alias.re 'restore --staged'
 
+# Test custom command completions by adding a command:
+
+set -p PATH $PWD
+echo "echo foo" > git-frobnicate
+chmod +x git-frobnicate
+
+complete -c git-frobnicate -xa 'foo bar baz'
+
+complete -C'git frobnicate '
+#CHECK: bar
+#CHECK: baz
+#CHECK: foo
+
 complete -C'git ' | grep '^add'\t
 # (note: actual tab character in the check here)
 #CHECK: add	Add file contents to the staging area
@@ -41,9 +54,11 @@ touch foo
 
 complete -C'git add '
 #CHECK: foo	Untracked file
+#CHECK: git-frobnicate	Untracked file
 
 complete -C'git add :'
 #CHECK: :/:foo	Untracked file
+#CHECK: :/:git-frobnicate	Untracked file
 
 git config alias.s status
 complete 'git s --s'
@@ -71,7 +86,7 @@ set -g __fish_git_prompt_show_informative_status 1
 set -g __fish_git_prompt_showuntrackedfiles 1
 fish_git_prompt
 echo
-#CHECK: (newbranch|…1)
+#CHECK: (newbranch|…2)
 set -e __fish_git_prompt_show_informative_status
 set -e __fish_git_prompt_showuntrackedfiles