treewide: noop: refer to `src.name` or similar where appropriate, part 3: more use cases

This continues where d8f7f6a5cee067b81bfaaa3aa079adb94ed7c01e left off. Similarly
to that commit, this commit this also points `sourceRoot`s to `src.name` and similar
instead of keeping hardcoded names, and edits other derivation attrs do do the same,
where appropriate.

Also, similarly to d8f7f6a5cee067b81bfaaa3aa079adb94ed7c01e some of expressions this
edits use `srcs` attribute with customly-named sources, so they have to be moved
into `let` blocks to keep evaluation efficient (the other, worse, way to do this
would to recurcively refer to `elemAt n finalAttrs.srcs` or, similarly, with `rec`).

1 files changed, 2 insertions, 2 deletions

diff --git a/pkgs/applications/version-management/gitqlient/default.nix b/pkgs/applications/version-management/gitqlient/default.nix
index 622c0f045135b..d7c1e46577e57 100644
--- a/pkgs/applications/version-management/gitqlient/default.nix
+++ b/pkgs/applications/version-management/gitqlient/default.nix
@@ -63,8 +63,8 @@ mkDerivation rec {
 
   postUnpack = ''
     for dep in AuxiliarCustomWidgets QPinnableTabWidget QLogger git; do
-      rmdir "source/src/$dep"
-      ln -sf "../../$dep" "source/src/$dep"
+      rmdir "${main_src.name}/src/$dep"
+      ln -sf "../../$dep" "${main_src.name}/src/$dep"
     done
   '';