From 06e270fd51daaf872382ad75a5f7a5607d9a87a8 Mon Sep 17 00:00:00 2001
From: William Carroll <wpcarro@gmail.com>
Date: Wed, 25 May 2022 10:06:11 -0700
Subject: buildGoModule: prefer verbose output when NIX_DEBUG set

> The -v flag causes vendor to print the names of vendored modules and packages
> to standard error.

The `-v` flag helped me debug a `buildGoModule` derivation yesterday evening.
---
 pkgs/development/go-modules/generic/default.nix | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/go-modules/generic/default.nix b/pkgs/development/go-modules/generic/default.nix
index 837f72a413d..b6af52d0efb 100644
--- a/pkgs/development/go-modules/generic/default.nix
+++ b/pkgs/development/go-modules/generic/default.nix
@@ -106,7 +106,10 @@ let
       mkdir -p "''${GOPATH}/pkg/mod/cache/download"
       go mod download
     '' else ''
-      go mod vendor
+      if (( "''${NIX_DEBUG:-0}" >= 1 )); then
+        goModVendorFlags+=(-v)
+      fi
+      go mod vendor "''${goModVendorFlags[@]}"
     ''}
 
       mkdir -p vendor
-- 
cgit 1.4.1