fix: dont break when given paths that are files. filter on them instead. (#13)

* fix: dont break when given paths that are files. filter on them instead.

* Update default.nix

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update checkmate.nix

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fmt

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: vic

checkmate.nix

@@ -138,6 +138,11 @@ in
           expected = 1;
         };
 
+        import-tree."test does not break if given a path to a file instead of a directory." = {
+          expr = lit.leafs ./tree/x/y.nix;
+          expected = [ ./tree/x/y.nix ];
+        };
+
         import-tree."test returns a module with a single imported nested module having leafs" = {
           expr =
             let

default.nix

@@ -29,7 +29,14 @@ let
         lib: root:
         let
           initialFilter = andNot (lib.hasInfix "/_") (lib.hasSuffix ".nix");
-          listFilesRecursive = x: if isImportTree x then treeFiles x else lib.filesystem.listFilesRecursive x;
+          listFilesRecursive =
+            x:
+            if isImportTree x then
+              treeFiles x
+            else if lib.pathIsDirectory x then
+              lib.filesystem.listFilesRecursive x
+            else
+              [ x ];
           treeFiles = t: (t.withLib lib).leafs.result;
         in
         lib.pipe