Add a description in the completion outputs

Make nix output completions in the form `completion\tdescription`.
This can't be used by bash (afaik), but other shells like zsh or fish
can display it along the completion choices

1 files changed, 1 insertions, 1 deletions

diff --git a/src/nix/main.cc b/src/nix/main.cc
index 1e9e07bc0..5056ceb78 100644
--- a/src/nix/main.cc
+++ b/src/nix/main.cc
@@ -208,7 +208,7 @@ void mainWrapped(int argc, char * * argv)
         if (completions) {
             std::cout << (pathCompletions ? "filenames\n" : "no-filenames\n");
             for (auto & s : *completions)
-                std::cout << s << "\n";
+                std::cout << s.completion << "\t" << s.description << "\n";
         }
     });