InstallableFlake: Handle missing attr in getCursors

Handle the case where none of getActualAttrPaths() actually exists,
in which case instead of returning an empty vector.

This fixes the case where the user misspells the attribute name in nix
search. Instead of getting no search results, now it shows an error with
suggestions.

Also remove InstallableFlake::getCursor() override since it's now
equivalent to the base class version.

2 files changed, 13 insertions, 35 deletions

diff --git a/src/libcmd/installables.cc b/src/libcmd/installables.cc
index 5090ea6d2..f8632a535 100644
--- a/src/libcmd/installables.cc
+++ b/src/libcmd/installables.cc
@@ -696,46 +696,28 @@ InstallableFlake::getCursors(EvalState & state)
 
     std::vector<ref<eval_cache::AttrCursor>> res;
 
-    for (auto & attrPath : getActualAttrPaths()) {
-        auto attr = root->findAlongAttrPath(parseAttrPath(state, attrPath));
-        if (attr) res.push_back(ref(*attr));
-    }
-
-    return res;
-}
-
-ref<eval_cache::AttrCursor> InstallableFlake::getCursor(EvalState & state)
-{
-    auto lockedFlake = getLockedFlake();
-
-    auto cache = openEvalCache(state, lockedFlake);
-    auto root = cache->getRoot();
-
     Suggestions suggestions;
-
     auto attrPaths = getActualAttrPaths();
 
     for (auto & attrPath : attrPaths) {
         debug("trying flake output attribute '%s'", attrPath);
 
-        auto attrOrSuggestions = root->findAlongAttrPath(
-            parseAttrPath(state, attrPath),
-            true
-        );
-
-        if (!attrOrSuggestions) {
-            suggestions += attrOrSuggestions.getSuggestions();
-            continue;
+        auto attr = root->findAlongAttrPath(parseAttrPath(state, attrPath));
+        if (attr) {
+            res.push_back(ref(*attr));
+        } else {
+            suggestions += attr.getSuggestions();
         }
-
-        return *attrOrSuggestions;
     }
 
-    throw Error(
-        suggestions,
-        "flake '%s' does not provide attribute %s",
-        flakeRef,
-        showAttrPaths(attrPaths));
+    if (res.size() == 0)
+        throw Error(
+            suggestions,
+            "flake '%s' does not provide attribute %s",
+            flakeRef,
+            showAttrPaths(attrPaths));
+
+    return res;
 }
 
 std::shared_ptr<flake::LockedFlake> InstallableFlake::getLockedFlake() const
diff --git a/src/libcmd/installables.hh b/src/libcmd/installables.hh
index 3d12639b0..d489315df 100644
--- a/src/libcmd/installables.hh
+++ b/src/libcmd/installables.hh
@@ -198,10 +198,6 @@ struct InstallableFlake : InstallableValue
     std::vector<ref<eval_cache::AttrCursor>>
     getCursors(EvalState & state) override;
 
-    /* Get a cursor to the first attrpath in getActualAttrPaths() that
-       exists, or throw an exception with suggestions if none exists. */
-    ref<eval_cache::AttrCursor> getCursor(EvalState & state) override;
-
     std::shared_ptr<flake::LockedFlake> getLockedFlake() const;
 
     FlakeRef nixpkgsFlakeRef() const override;