Always enter first level of attrset in nix search

This makes nix search always go through the first level of an
attribute set, even if it's not a top level attribute. For instance,
you can now list all GHC compilers with:

$ nix search nixpkgs#haskell.compiler
...

This is similar to how nix-env works when you pass in -A.

1 files changed, 7 insertions, 4 deletions

diff --git a/src/nix/search.cc b/src/nix/search.cc
index 9f864b3a4..c52a48d4e 100644
--- a/src/nix/search.cc
+++ b/src/nix/search.cc
@@ -81,9 +81,9 @@ struct CmdSearch : InstallableCommand, MixJSON
 
         uint64_t results = 0;
 
-        std::function<void(eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath)> visit;
+        std::function<void(eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath, bool initialRecurse)> visit;
 
-        visit = [&](eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath)
+        visit = [&](eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath, bool initialRecurse)
         {
             Activity act(*logger, lvlInfo, actUnknown,
                 fmt("evaluating '%s'", concatStringsSep(".", attrPath)));
@@ -94,7 +94,7 @@ struct CmdSearch : InstallableCommand, MixJSON
                         auto cursor2 = cursor.getAttr(attr);
                         auto attrPath2(attrPath);
                         attrPath2.push_back(attr);
-                        visit(*cursor2, attrPath2);
+                        visit(*cursor2, attrPath2, false);
                     }
                 };
 
@@ -150,6 +150,9 @@ struct CmdSearch : InstallableCommand, MixJSON
                     || (attrPath[0] == "packages" && attrPath.size() <= 2))
                     recurse();
 
+                else if (initialRecurse)
+                    recurse();
+
                 else if (attrPath[0] == "legacyPackages" && attrPath.size() > 2) {
                     auto attr = cursor.maybeGetAttr(state->sRecurseForDerivations);
                     if (attr && attr->getBool())
@@ -163,7 +166,7 @@ struct CmdSearch : InstallableCommand, MixJSON
         };
 
         for (auto & [cursor, prefix] : installable->getCursors(*state))
-            visit(*cursor, parseAttrPath(*state, prefix));
+            visit(*cursor, parseAttrPath(*state, prefix), true);
 
         if (!json && !results)
             throw Error("no results for the given search term(s)!");