From f63dc715c1edd3b2c13f3654abb0c76b97732557 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Tue, 1 Apr 2025 18:37:21 +0200
Subject: [PATCH] Fix missing file error messages from 'import'

---
 src/libutil/mounted-source-accessor.cc  |  6 ++++++
 tests/functional/flakes/source-paths.sh | 15 +++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/libutil/mounted-source-accessor.cc b/src/libutil/mounted-source-accessor.cc
index 15da826d2..89063b10f 100644
--- a/src/libutil/mounted-source-accessor.cc
+++ b/src/libutil/mounted-source-accessor.cc
@@ -23,6 +23,12 @@ struct MountedSourceAccessorImpl : MountedSourceAccessor
         return accessor->readFile(subpath);
     }
 
+    Stat lstat(const CanonPath & path) override
+    {
+        auto [accessor, subpath] = resolve(path);
+        return accessor->lstat(subpath);
+    }
+
     std::optional<Stat> maybeLstat(const CanonPath & path) override
     {
         auto [accessor, subpath] = resolve(path);
diff --git a/tests/functional/flakes/source-paths.sh b/tests/functional/flakes/source-paths.sh
index 6cd0917aa..3aa3683c2 100644
--- a/tests/functional/flakes/source-paths.sh
+++ b/tests/functional/flakes/source-paths.sh
@@ -14,6 +14,8 @@ cat > "$repo/flake.nix" <<EOF
     x = 1;
     y = assert false; 1;
     z = builtins.readFile ./foo;
+    a = import ./foo;
+    b = import ./dir;
   };
 }
 EOF
@@ -32,11 +34,24 @@ expectStderr 1 nix eval "git+file://$repo?ref=master#y" | grepQuiet "at «git+fi
 
 expectStderr 1 nix eval "$repo#z" | grepQuiet "error: Path 'foo' does not exist in Git repository \"$repo\"."
 expectStderr 1 nix eval "git+file://$repo?ref=master#z" | grepQuiet "error: '«git+file://$repo?ref=master&rev=.*»/foo' does not exist"
+expectStderr 1 nix eval "$repo#a" | grepQuiet "error: Path 'foo' does not exist in Git repository \"$repo\"."
 
 echo 123 > "$repo/foo"
 
 expectStderr 1 nix eval "$repo#z" | grepQuiet "error: Path 'foo' in the repository \"$repo\" is not tracked by Git."
+expectStderr 1 nix eval "$repo#a" | grepQuiet "error: Path 'foo' in the repository \"$repo\" is not tracked by Git."
 
 git -C "$repo" add "$repo/foo"
 
 [[ $(nix eval --raw "$repo#z") = 123 ]]
+
+expectStderr 1 nix eval "$repo#b" | grepQuiet "error: Path 'dir' does not exist in Git repository \"$repo\"."
+
+mkdir -p "$repo/dir"
+echo 456 > "$repo/dir/default.nix"
+
+expectStderr 1 nix eval "$repo#b" | grepQuiet "error: Path 'dir' in the repository \"$repo\" is not tracked by Git."
+
+git -C "$repo" add "$repo/dir/default.nix"
+
+[[ $(nix eval "$repo#b") = 456 ]]