3 files changed, 18 insertions, 6 deletions

diff --git a/crates/libanalysis/src/imp.rs b/crates/libanalysis/src/imp.rs
index 3ea27947e..50855551e 100644
--- a/crates/libanalysis/src/imp.rs
+++ b/crates/libanalysis/src/imp.rs
@@ -57,9 +57,8 @@ impl AnalysisHostImpl {
         }
         self.data_mut().crate_graph = graph;
     }
-    pub fn add_library(&mut self, files: impl Iterator<Item=(FileId, String)>) {
-        let libs = ReadonlySourceRoot::new(files);
-        self.data_mut().libs.push(Arc::new(libs));
+    pub fn add_library(&mut self, root: ReadonlySourceRoot) {
+        self.data_mut().libs.push(Arc::new(root));
     }
     fn data_mut(&mut self) -> &mut WorldData {
         Arc::make_mut(&mut self.data)
diff --git a/crates/libanalysis/src/lib.rs b/crates/libanalysis/src/lib.rs
index e9e0c51d5..a8152939b 100644
--- a/crates/libanalysis/src/lib.rs
+++ b/crates/libanalysis/src/lib.rs
@@ -68,8 +68,8 @@ impl AnalysisHost {
     pub fn set_crate_graph(&mut self, graph: CrateGraph) {
         self.imp.set_crate_graph(graph)
     }
-    pub fn add_library(&mut self, files: impl Iterator<Item=(FileId, String)>) {
-        self.imp.add_library(files)
+    pub fn add_library(&mut self, data: LibraryData) {
+        self.imp.add_library(data.root)
     }
 }
 
@@ -216,3 +216,15 @@ impl Analysis {
         self.imp.diagnostics(file_id)
     }
 }
+
+#[derive(Debug)]
+pub struct LibraryData {
+    root: roots::ReadonlySourceRoot
+}
+
+impl LibraryData {
+    pub fn prepare(files: Vec<(FileId, String)>) -> LibraryData {
+        let root = roots::ReadonlySourceRoot::new(files);
+        LibraryData { root }
+    }
+}
diff --git a/crates/libanalysis/src/roots.rs b/crates/libanalysis/src/roots.rs
index a65668c9b..f1bc72e33 100644
--- a/crates/libanalysis/src/roots.rs
+++ b/crates/libanalysis/src/roots.rs
@@ -136,9 +136,10 @@ pub(crate) struct ReadonlySourceRoot {
 }
 
 impl ReadonlySourceRoot {
-    pub fn new(files: impl Iterator<Item=(FileId, String)>) -> ReadonlySourceRoot {
+    pub fn new(files: Vec<(FileId, String)>) -> ReadonlySourceRoot {
         let mut module_map = ModuleMap::new();
         let file_map: HashMap<FileId, FileData> = files
+            .into_iter()
             .map(|(id, text)| {
                 module_map.update_file(id, ChangeKind::Insert);
                 (id, FileData::new(text))