Fix listfiles & add materialize

src/Files.jl

@@ -3,7 +3,7 @@
 export listfiles
 
 using Configurations: @option
-using FileTrees: FileTree, Path, files
+using FileTrees: FileTree, mapsubtrees, path
 using Glob: GlobMatch
 
 @option struct ExpressFileTree
@@ -12,12 +12,19 @@ using Glob: GlobMatch
     output_pattern::Union{String,Regex,GlobMatch}
 end
 
-function listfiles(patterns, root_dir=pwd())
-    tree = FileTree(root_dir)
-    return map((patterns.first, patterns.second)) do pattern
-        subtree = tree[pattern]
-        abspath.(Path.(files(subtree)))
+function listfiles(patterns::Pair, root_dir=pwd())
+    tree = FileTree(expanduser(root_dir))
+    io = map(patterns) do pattern
+        files = String[]
+        mapsubtrees(tree, pattern) do subtree
+            push!(files, abspath(path(subtree)))
+        end
+        files
     end
+    return Tuple(io)
 end
 
+materialize(config::ExpressFileTree) =
+    listfiles(config.input_pattern => config.output_pattern, config.root_dir)
+
 # end