Merge pull request #9648 from cole-h/nix-shell-ordering

nix shell: reflect command line order in PATH order

(cherry picked from commit b91c935c2faf08ced2c763dcd2a831f26d84fa86)
Change-Id: If16c120bb74857c2817366e74e5b0877eb997260

src/libcmd/installables.cc

@@ -674,7 +674,7 @@ BuiltPaths Installable::toBuiltPaths(
     }
 }
 
-StorePathSet Installable::toStorePaths(
+StorePathSet Installable::toStorePathSet(
     ref<Store> evalStore,
     ref<Store> store,
     Realise mode, OperateOn operateOn,
@@ -688,13 +688,27 @@ StorePathSet Installable::toStorePaths(
     return outPaths;
 }
 
+StorePaths Installable::toStorePaths(
+    ref<Store> evalStore,
+    ref<Store> store,
+    Realise mode, OperateOn operateOn,
+    const Installables & installables)
+{
+    StorePaths outPaths;
+    for (auto & path : toBuiltPaths(evalStore, store, mode, operateOn, installables)) {
+        auto thisOutPaths = path.outPaths();
+        outPaths.insert(outPaths.end(), thisOutPaths.begin(), thisOutPaths.end());
+    }
+    return outPaths;
+}
+
 StorePath Installable::toStorePath(
     ref<Store> evalStore,
     ref<Store> store,
     Realise mode, OperateOn operateOn,
     ref<Installable> installable)
 {
-    auto paths = toStorePaths(evalStore, store, mode, operateOn, {installable});
+    auto paths = toStorePathSet(evalStore, store, mode, operateOn, {installable});
 
     if (paths.size() != 1)
         throw Error("argument '%s' should evaluate to one store path", installable->what());

src/libcmd/installables.hh

@@ -166,7 +166,14 @@ struct Installable
         const Installables & installables,
         BuildMode bMode = bmNormal);
 
-    static std::set<StorePath> toStorePaths(
+    static std::set<StorePath> toStorePathSet(
+        ref<Store> evalStore,
+        ref<Store> store,
+        Realise mode,
+        OperateOn operateOn,
+        const Installables & installables);
+
+    static std::vector<StorePath> toStorePaths(
         ref<Store> evalStore,
         ref<Store> store,
         Realise mode,