From 81cd0a113b8da1485c2f892c9dd9edb541f139ad Mon Sep 17 00:00:00 2001
From: regnat <rg@regnat.ovh>
Date: Fri, 14 Jan 2022 13:41:45 +0100
Subject: [PATCH] Start the pager early-enough in `nix why-depends`
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`nix why-depends` is piping its output into a pager by default.
However the pager was only started after the first path is printed,
causing it to be excluded from the pager output.

(Actually the pager was started *inside* the recursive function that was
printing the dependency chain, so a new instance was started at each
level. It’s a little miracle that it worked at all).

Fix #5911
---
 src/nix/why-depends.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/nix/why-depends.cc b/src/nix/why-depends.cc
index e27f56ef5..dd43bd1c3 100644
--- a/src/nix/why-depends.cc
+++ b/src/nix/why-depends.cc
@@ -239,7 +239,6 @@ struct CmdWhyDepends : SourceExprCommand
 
             visitPath(pathS);
 
-            RunPager pager;
             for (auto & ref : refs) {
                 std::string hash(ref.second->path.hashPart());
 
@@ -259,6 +258,7 @@ struct CmdWhyDepends : SourceExprCommand
             }
         };
 
+        RunPager pager;
         try {
             printNode(graph.at(packagePath), "", "");
         } catch (BailOut & ) { }