Avoid failing if vc backend doesn't implement ignore-completion-table

* project.el (project-ignores): Handle vc-not-supported signals

diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index ae9bf035717766e474f20709d1df703d97569697..e420a4ccca7c9e4a7a759c0e5a6b2e7517019d9f 100644 (file)
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -604,7 +604,9 @@ backend implementation of `project-external-roots'.")
                  (replace-match "./" t t entry 1)
                (concat "./" entry)))
             (t entry)))
-         (vc-call-backend backend 'ignore-completion-table root))))
+         (condition-case nil
+             (vc-call-backend backend 'ignore-completion-table root)
+           (vc-not-supported () nil)))))
      (project--value-in-dir 'project-vc-ignores root)
      (mapcar
       (lambda (dir)