diff --git a/crates/rust-analyzer/src/from_proto.rs b/crates/rust-analyzer/src/from_proto.rs
index de995412c64..c671b5f649c 100644
--- a/crates/rust-analyzer/src/from_proto.rs
+++ b/crates/rust-analyzer/src/from_proto.rs
@@ -1,12 +1,14 @@
 //! Conversion lsp_types types to rust-analyzer specific ones.
 use std::convert::TryFrom;
 
-use ide::{Annotation, AnnotationKind, AssistKind, LineColUtf16, LineIndex};
+use ide::{Annotation, AnnotationKind, AssistKind, LineColUtf16};
 use ide_db::base_db::{FileId, FilePosition, FileRange};
 use syntax::{TextRange, TextSize};
 use vfs::AbsPathBuf;
 
-use crate::{from_json, global_state::GlobalStateSnapshot, lsp_ext, Result};
+use crate::{
+    from_json, global_state::GlobalStateSnapshot, line_endings::LineIndex, lsp_ext, Result,
+};
 
 pub(crate) fn abs_path(url: &lsp_types::Url) -> Result<AbsPathBuf> {
     let path = url.to_file_path().map_err(|()| "url is not a file")?;
@@ -19,8 +21,8 @@ pub(crate) fn vfs_path(url: &lsp_types::Url) -> Result<vfs::VfsPath> {
 
 pub(crate) fn offset(line_index: &LineIndex, position: lsp_types::Position) -> TextSize {
     let line_col = LineColUtf16 { line: position.line as u32, col: position.character as u32 };
-    let line_col = line_index.to_utf8(line_col);
-    line_index.offset(line_col)
+    let line_col = line_index.index.to_utf8(line_col);
+    line_index.index.offset(line_col)
 }
 
 pub(crate) fn text_range(line_index: &LineIndex, range: lsp_types::Range) -> TextRange {
@@ -38,8 +40,8 @@ pub(crate) fn file_position(
     tdpp: lsp_types::TextDocumentPositionParams,
 ) -> Result<FilePosition> {
     let file_id = file_id(world, &tdpp.text_document.uri)?;
-    let line_index = world.analysis.file_line_index(file_id)?;
-    let offset = offset(&*line_index, tdpp.position);
+    let line_index = world.file_line_index(file_id)?;
+    let offset = offset(&line_index, tdpp.position);
     Ok(FilePosition { file_id, offset })
 }
 
@@ -49,7 +51,7 @@ pub(crate) fn file_range(
     range: lsp_types::Range,
 ) -> Result<FileRange> {
     let file_id = file_id(world, &text_document_identifier.uri)?;
-    let line_index = world.analysis.file_line_index(file_id)?;
+    let line_index = world.file_line_index(file_id)?;
     let range = text_range(&line_index, range);
     Ok(FileRange { file_id, range })
 }
@@ -79,7 +81,7 @@ pub(crate) fn annotation(
         lsp_ext::CodeLensResolveData::Impls(params) => {
             let file_id =
                 world.url_to_file_id(&params.text_document_position_params.text_document.uri)?;
-            let line_index = world.analysis.file_line_index(file_id)?;
+            let line_index = world.file_line_index(file_id)?;
 
             Ok(Annotation {
                 range: text_range(&line_index, code_lens.range),
@@ -91,7 +93,7 @@ pub(crate) fn annotation(
         }
         lsp_ext::CodeLensResolveData::References(params) => {
             let file_id = world.url_to_file_id(&params.text_document.uri)?;
-            let line_index = world.analysis.file_line_index(file_id)?;
+            let line_index = world.file_line_index(file_id)?;
 
             Ok(Annotation {
                 range: text_range(&line_index, code_lens.range),
diff --git a/crates/rust-analyzer/src/global_state.rs b/crates/rust-analyzer/src/global_state.rs
index c3bc8791d4b..ffef33430ca 100644
--- a/crates/rust-analyzer/src/global_state.rs
+++ b/crates/rust-analyzer/src/global_state.rs
@@ -7,7 +7,7 @@ use std::{sync::Arc, time::Instant};
 
 use crossbeam_channel::{unbounded, Receiver, Sender};
 use flycheck::FlycheckHandle;
-use ide::{Analysis, AnalysisHost, Change, FileId};
+use ide::{Analysis, AnalysisHost, Cancelable, Change, FileId};
 use ide_db::base_db::{CrateId, VfsPath};
 use lsp_types::{SemanticTokens, Url};
 use parking_lot::{Mutex, RwLock};
@@ -22,7 +22,7 @@ use crate::{
     diagnostics::{CheckFixes, DiagnosticCollection},
     document::DocumentData,
     from_proto,
-    line_endings::LineEndings,
+    line_endings::{LineEndings, LineIndex},
     main_loop::Task,
     op_queue::OpQueue,
     reload::SourceRootConfig,
@@ -271,8 +271,11 @@ impl GlobalStateSnapshot {
         file_id_to_url(&self.vfs.read().0, id)
     }
 
-    pub(crate) fn file_line_endings(&self, id: FileId) -> LineEndings {
-        self.vfs.read().1[&id]
+    pub(crate) fn file_line_index(&self, file_id: FileId) -> Cancelable<LineIndex> {
+        let endings = self.vfs.read().1[&file_id];
+        let index = self.analysis.file_line_index(file_id)?;
+        let res = LineIndex { index, endings };
+        Ok(res)
     }
 
     pub(crate) fn url_file_version(&self, url: &Url) -> Option<i32> {
diff --git a/crates/rust-analyzer/src/handlers.rs b/crates/rust-analyzer/src/handlers.rs
index 2d697c75f50..d8b00e9c582 100644
--- a/crates/rust-analyzer/src/handlers.rs
+++ b/crates/rust-analyzer/src/handlers.rs
@@ -5,12 +5,11 @@
 use std::{
     io::Write as _,
     process::{self, Stdio},
-    sync::Arc,
 };
 
 use ide::{
-    AnnotationConfig, FileId, FilePosition, FileRange, HoverAction, HoverGotoTypeData, LineIndex,
-    Query, RangeInfo, Runnable, RunnableKind, SearchScope, SourceChange, TextEdit,
+    AnnotationConfig, FileId, FilePosition, FileRange, HoverAction, HoverGotoTypeData, Query,
+    RangeInfo, Runnable, RunnableKind, SearchScope, SourceChange, TextEdit,
 };
 use ide_db::SymbolKind;
 use itertools::Itertools;
@@ -38,6 +37,7 @@ use crate::{
     from_proto,
     global_state::{GlobalState, GlobalStateSnapshot},
     line_endings::LineEndings,
+    line_endings::LineIndex,
     lsp_ext::{self, InlayHint, InlayHintsParams},
     lsp_utils::all_edits_are_disjoint,
     to_proto, LspError, Result,
@@ -100,7 +100,7 @@ pub(crate) fn handle_syntax_tree(
 ) -> Result<String> {
     let _p = profile::span("handle_syntax_tree");
     let id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(id)?;
+    let line_index = snap.file_line_index(id)?;
     let text_range = params.range.map(|r| from_proto::text_range(&line_index, r));
     let res = snap.analysis.syntax_tree(id, text_range)?;
     Ok(res)
@@ -122,7 +122,7 @@ pub(crate) fn handle_expand_macro(
 ) -> Result<Option<lsp_ext::ExpandedMacro>> {
     let _p = profile::span("handle_expand_macro");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let offset = from_proto::offset(&line_index, params.position);
 
     let res = snap.analysis.expand_macro(FilePosition { file_id, offset })?;
@@ -135,7 +135,7 @@ pub(crate) fn handle_selection_range(
 ) -> Result<Option<Vec<lsp_types::SelectionRange>>> {
     let _p = profile::span("handle_selection_range");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let res: Result<Vec<lsp_types::SelectionRange>> = params
         .positions
         .into_iter()
@@ -178,7 +178,7 @@ pub(crate) fn handle_matching_brace(
 ) -> Result<Vec<Position>> {
     let _p = profile::span("handle_matching_brace");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let res = params
         .positions
         .into_iter()
@@ -200,8 +200,7 @@ pub(crate) fn handle_join_lines(
 ) -> Result<Vec<lsp_types::TextEdit>> {
     let _p = profile::span("handle_join_lines");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
-    let line_endings = snap.file_line_endings(file_id);
+    let line_index = snap.file_line_index(file_id)?;
     let mut res = TextEdit::default();
     for range in params.ranges {
         let range = from_proto::text_range(&line_index, range);
@@ -213,7 +212,7 @@ pub(crate) fn handle_join_lines(
             }
         }
     }
-    let res = to_proto::text_edit_vec(&line_index, line_endings, res);
+    let res = to_proto::text_edit_vec(&line_index, res);
     Ok(res)
 }
 
@@ -227,9 +226,8 @@ pub(crate) fn handle_on_enter(
         None => return Ok(None),
         Some(it) => it,
     };
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
-    let line_endings = snap.file_line_endings(position.file_id);
-    let edit = to_proto::snippet_text_edit_vec(&line_index, line_endings, true, edit);
+    let line_index = snap.file_line_index(position.file_id)?;
+    let edit = to_proto::snippet_text_edit_vec(&line_index, true, edit);
     Ok(Some(edit))
 }
 
@@ -240,8 +238,7 @@ pub(crate) fn handle_on_type_formatting(
 ) -> Result<Option<Vec<lsp_types::TextEdit>>> {
     let _p = profile::span("handle_on_type_formatting");
     let mut position = from_proto::file_position(&snap, params.text_document_position)?;
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
-    let line_endings = snap.file_line_endings(position.file_id);
+    let line_index = snap.file_line_index(position.file_id)?;
 
     // in `ide`, the `on_type` invariant is that
     // `text.char_at(position) == typed_char`.
@@ -269,7 +266,7 @@ pub(crate) fn handle_on_type_formatting(
     // This should be a single-file edit
     let (_, edit) = edit.source_file_edits.into_iter().next().unwrap();
 
-    let change = to_proto::text_edit_vec(&line_index, line_endings, edit);
+    let change = to_proto::text_edit_vec(&line_index, edit);
     Ok(Some(change))
 }
 
@@ -279,7 +276,7 @@ pub(crate) fn handle_document_symbol(
 ) -> Result<Option<lsp_types::DocumentSymbolResponse>> {
     let _p = profile::span("handle_document_symbol");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
 
     let mut parents: Vec<(lsp_types::DocumentSymbol, Option<usize>)> = Vec::new();
 
@@ -535,7 +532,7 @@ pub(crate) fn handle_runnables(
 ) -> Result<Vec<lsp_ext::Runnable>> {
     let _p = profile::span("handle_runnables");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let offset = params.position.map(|it| from_proto::offset(&line_index, it));
     let cargo_spec = CargoTargetSpec::for_file(&snap, file_id)?;
 
@@ -645,14 +642,12 @@ pub(crate) fn handle_completion(
         None => return Ok(None),
         Some(items) => items,
     };
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
-    let line_endings = snap.file_line_endings(position.file_id);
+    let line_index = snap.file_line_index(position.file_id)?;
 
     let items: Vec<CompletionItem> = items
         .into_iter()
         .flat_map(|item| {
-            let mut new_completion_items =
-                to_proto::completion_item(&line_index, line_endings, item.clone());
+            let mut new_completion_items = to_proto::completion_item(&line_index, item.clone());
 
             if completion_config.enable_imports_on_the_fly {
                 for new_item in &mut new_completion_items {
@@ -693,8 +688,7 @@ pub(crate) fn handle_completion_resolve(
     };
 
     let file_id = from_proto::file_id(&snap, &resolve_data.position.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
-    let line_endings = snap.file_line_endings(file_id);
+    let line_index = snap.file_line_index(file_id)?;
     let offset = from_proto::offset(&line_index, resolve_data.position.position);
 
     let additional_edits = snap
@@ -707,9 +701,7 @@ pub(crate) fn handle_completion_resolve(
             resolve_data.import_for_trait_assoc_item,
         )?
         .into_iter()
-        .flat_map(|edit| {
-            edit.into_iter().map(|indel| to_proto::text_edit(&line_index, line_endings, indel))
-        })
+        .flat_map(|edit| edit.into_iter().map(|indel| to_proto::text_edit(&line_index, indel)))
         .collect_vec();
 
     if !all_edits_are_disjoint(&original_completion, &additional_edits) {
@@ -738,7 +730,7 @@ pub(crate) fn handle_folding_range(
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
     let folds = snap.analysis.folding_ranges(file_id)?;
     let text = snap.analysis.file_text(file_id)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let line_folding_only = snap.config.line_folding_only();
     let res = folds
         .into_iter()
@@ -775,7 +767,7 @@ pub(crate) fn handle_hover(
             None => return Ok(None),
             Some(info) => info,
         };
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
+    let line_index = snap.file_line_index(position.file_id)?;
     let range = to_proto::range(&line_index, info.range);
     let hover = lsp_ext::Hover {
         hover: lsp_types::Hover {
@@ -797,7 +789,7 @@ pub(crate) fn handle_prepare_rename(
 
     let change = snap.analysis.prepare_rename(position)?.map_err(to_proto::rename_error)?;
 
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
+    let line_index = snap.file_line_index(position.file_id)?;
     let range = to_proto::range(&line_index, change.range);
     Ok(Some(PrepareRenameResponse::Range(range)))
 }
@@ -857,8 +849,7 @@ pub(crate) fn handle_formatting(
     let file = snap.analysis.file_text(file_id)?;
     let crate_ids = snap.analysis.crate_for(file_id)?;
 
-    let file_line_index = snap.analysis.file_line_index(file_id)?;
-    let file_line_endings = snap.file_line_endings(file_id);
+    let line_index = snap.file_line_index(file_id)?;
 
     let mut rustfmt = match snap.config.rustfmt() {
         RustfmtConfig::Rustfmt { extra_args } => {
@@ -935,24 +926,19 @@ pub(crate) fn handle_formatting(
 
     let (new_text, new_line_endings) = LineEndings::normalize(captured_stdout);
 
-    if file_line_endings != new_line_endings {
+    if line_index.endings != new_line_endings {
         // If line endings are different, send the entire file.
         // Diffing would not work here, as the line endings might be the only
         // difference.
         Ok(Some(to_proto::text_edit_vec(
-            &file_line_index,
-            new_line_endings,
+            &line_index,
             TextEdit::replace(TextRange::up_to(TextSize::of(&*file)), new_text),
         )))
     } else if *file == new_text {
         // The document is already formatted correctly -- no edits needed.
         Ok(None)
     } else {
-        Ok(Some(to_proto::text_edit_vec(
-            &file_line_index,
-            file_line_endings,
-            diff(&file, &new_text),
-        )))
+        Ok(Some(to_proto::text_edit_vec(&line_index, diff(&file, &new_text))))
     }
 }
 
@@ -969,7 +955,7 @@ pub(crate) fn handle_code_action(
     }
 
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let range = from_proto::text_range(&line_index, params.range);
     let frange = FileRange { file_id, range };
 
@@ -1010,7 +996,7 @@ pub(crate) fn handle_code_action(
 fn add_quick_fixes(
     snap: &GlobalStateSnapshot,
     frange: FileRange,
-    line_index: &Arc<LineIndex>,
+    line_index: &LineIndex,
     acc: &mut Vec<lsp_ext::CodeAction>,
 ) -> Result<()> {
     let diagnostics = snap.analysis.diagnostics(&snap.config.diagnostics(), frange.file_id)?;
@@ -1052,7 +1038,7 @@ pub(crate) fn handle_code_action_resolve(
     };
 
     let file_id = from_proto::file_id(&snap, &params.code_action_params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     let range = from_proto::text_range(&line_index, params.code_action_params.range);
     let frange = FileRange { file_id, range };
 
@@ -1131,7 +1117,7 @@ pub(crate) fn handle_document_highlight(
 ) -> Result<Option<Vec<DocumentHighlight>>> {
     let _p = profile::span("handle_document_highlight");
     let position = from_proto::file_position(&snap, params.text_document_position_params)?;
-    let line_index = snap.analysis.file_line_index(position.file_id)?;
+    let line_index = snap.file_line_index(position.file_id)?;
 
     let refs = match snap
         .analysis
@@ -1192,7 +1178,7 @@ pub(crate) fn publish_diagnostics(
     file_id: FileId,
 ) -> Result<Vec<Diagnostic>> {
     let _p = profile::span("publish_diagnostics");
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
 
     let diagnostics: Vec<Diagnostic> = snap
         .analysis
@@ -1226,7 +1212,7 @@ pub(crate) fn handle_inlay_hints(
 ) -> Result<Vec<InlayHint>> {
     let _p = profile::span("handle_inlay_hints");
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
     Ok(snap
         .analysis
         .inlay_hints(file_id, &snap.config.inlay_hints())?
@@ -1277,7 +1263,7 @@ pub(crate) fn handle_call_hierarchy_incoming(
 
     for call_item in call_items.into_iter() {
         let file_id = call_item.target.file_id;
-        let line_index = snap.analysis.file_line_index(file_id)?;
+        let line_index = snap.file_line_index(file_id)?;
         let item = to_proto::call_hierarchy_item(&snap, call_item.target)?;
         res.push(CallHierarchyIncomingCall {
             from: item,
@@ -1312,7 +1298,7 @@ pub(crate) fn handle_call_hierarchy_outgoing(
 
     for call_item in call_items.into_iter() {
         let file_id = call_item.target.file_id;
-        let line_index = snap.analysis.file_line_index(file_id)?;
+        let line_index = snap.file_line_index(file_id)?;
         let item = to_proto::call_hierarchy_item(&snap, call_item.target)?;
         res.push(CallHierarchyOutgoingCall {
             to: item,
@@ -1335,7 +1321,7 @@ pub(crate) fn handle_semantic_tokens_full(
 
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
     let text = snap.analysis.file_text(file_id)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
 
     let highlights = snap.analysis.highlight(file_id)?;
     let semantic_tokens = to_proto::semantic_tokens(&text, &line_index, highlights);
@@ -1354,7 +1340,7 @@ pub(crate) fn handle_semantic_tokens_full_delta(
 
     let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
     let text = snap.analysis.file_text(file_id)?;
-    let line_index = snap.analysis.file_line_index(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
 
     let highlights = snap.analysis.highlight(file_id)?;
 
@@ -1384,7 +1370,7 @@ pub(crate) fn handle_semantic_tokens_range(
 
     let frange = from_proto::file_range(&snap, params.text_document, params.range)?;
     let text = snap.analysis.file_text(frange.file_id)?;
-    let line_index = snap.analysis.file_line_index(frange.file_id)?;
+    let line_index = snap.file_line_index(frange.file_id)?;
 
     let highlights = snap.analysis.highlight_range(frange)?;
     let semantic_tokens = to_proto::semantic_tokens(&text, &line_index, highlights);
@@ -1432,7 +1418,7 @@ fn show_impl_command_link(
     if snap.config.hover().implementations {
         if let Some(nav_data) = snap.analysis.goto_implementation(*position).unwrap_or(None) {
             let uri = to_proto::url(snap, position.file_id);
-            let line_index = snap.analysis.file_line_index(position.file_id).ok()?;
+            let line_index = snap.file_line_index(position.file_id).ok()?;
             let position = to_proto::position(&line_index, position.offset);
             let locations: Vec<_> = nav_data
                 .info
diff --git a/crates/rust-analyzer/src/line_endings.rs b/crates/rust-analyzer/src/line_endings.rs
index bf0e255d9d9..cc152c529d1 100644
--- a/crates/rust-analyzer/src/line_endings.rs
+++ b/crates/rust-analyzer/src/line_endings.rs
@@ -2,6 +2,13 @@
 //! This module does line ending conversion and detection (so that we can
 //! convert back to `\r\n` on the way out).
 
+use std::sync::Arc;
+
+pub(crate) struct LineIndex {
+    pub(crate) index: Arc<ide::LineIndex>,
+    pub(crate) endings: LineEndings,
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub(crate) enum LineEndings {
     Unix,
diff --git a/crates/rust-analyzer/src/lsp_utils.rs b/crates/rust-analyzer/src/lsp_utils.rs
index 2d06fe538d7..25162185e04 100644
--- a/crates/rust-analyzer/src/lsp_utils.rs
+++ b/crates/rust-analyzer/src/lsp_utils.rs
@@ -1,11 +1,14 @@
 //! Utilities for LSP-related boilerplate code.
-use std::{error::Error, ops::Range};
+use std::{error::Error, ops::Range, sync::Arc};
 
-use ide::LineIndex;
 use ide_db::base_db::Canceled;
 use lsp_server::Notification;
 
-use crate::{from_proto, global_state::GlobalState};
+use crate::{
+    from_proto,
+    global_state::GlobalState,
+    line_endings::{LineEndings, LineIndex},
+};
 
 pub(crate) fn is_canceled(e: &(dyn Error + 'static)) -> bool {
     e.downcast_ref::<Canceled>().is_some()
@@ -90,7 +93,12 @@ pub(crate) fn apply_document_changes(
     old_text: &mut String,
     content_changes: Vec<lsp_types::TextDocumentContentChangeEvent>,
 ) {
-    let mut line_index = LineIndex::new(old_text);
+    let mut line_index = LineIndex {
+        index: Arc::new(ide::LineIndex::new(old_text)),
+        // We don't care about line endings here.
+        endings: LineEndings::Unix,
+    };
+
     // The changes we got must be applied sequentially, but can cross lines so we
     // have to keep our line index updated.
     // Some clients (e.g. Code) sort the ranges in reverse. As an optimization, we
@@ -115,7 +123,7 @@ pub(crate) fn apply_document_changes(
         match change.range {
             Some(range) => {
                 if !index_valid.covers(range.end.line) {
-                    line_index = LineIndex::new(&old_text);
+                    line_index.index = Arc::new(ide::LineIndex::new(&old_text));
                 }
                 index_valid = IndexValid::UpToLineExclusive(range.start.line);
                 let range = from_proto::text_range(&line_index, range);
diff --git a/crates/rust-analyzer/src/to_proto.rs b/crates/rust-analyzer/src/to_proto.rs
index ec5e8aa73c3..43e29ef04ef 100644
--- a/crates/rust-analyzer/src/to_proto.rs
+++ b/crates/rust-analyzer/src/to_proto.rs
@@ -7,22 +7,23 @@ use std::{
 use ide::{
     Annotation, AnnotationKind, Assist, AssistKind, CallInfo, CompletionItem, CompletionItemKind,
     Documentation, FileId, FileRange, FileSystemEdit, Fold, FoldKind, Highlight, HlMod, HlPunct,
-    HlRange, HlTag, Indel, InlayHint, InlayKind, InsertTextFormat, LineIndex, Markup,
-    NavigationTarget, ReferenceAccess, RenameError, Runnable, Severity, SourceChange, TextEdit,
-    TextRange, TextSize,
+    HlRange, HlTag, Indel, InlayHint, InlayKind, InsertTextFormat, Markup, NavigationTarget,
+    ReferenceAccess, RenameError, Runnable, Severity, SourceChange, TextEdit, TextRange, TextSize,
 };
 use ide_db::SymbolKind;
 use itertools::Itertools;
 use serde_json::to_value;
 
 use crate::{
-    cargo_target_spec::CargoTargetSpec, global_state::GlobalStateSnapshot,
-    line_endings::LineEndings, lsp_ext, semantic_tokens, Result,
+    cargo_target_spec::CargoTargetSpec,
+    global_state::GlobalStateSnapshot,
+    line_endings::{LineEndings, LineIndex},
+    lsp_ext, semantic_tokens, Result,
 };
 
 pub(crate) fn position(line_index: &LineIndex, offset: TextSize) -> lsp_types::Position {
-    let line_col = line_index.line_col(offset);
-    let line_col = line_index.to_utf16(line_col);
+    let line_col = line_index.index.line_col(offset);
+    let line_col = line_index.index.to_utf16(line_col);
     lsp_types::Position::new(line_col.line, line_col.col)
 }
 
@@ -123,13 +124,9 @@ pub(crate) fn completion_item_kind(
     }
 }
 
-pub(crate) fn text_edit(
-    line_index: &LineIndex,
-    line_endings: LineEndings,
-    indel: Indel,
-) -> lsp_types::TextEdit {
+pub(crate) fn text_edit(line_index: &LineIndex, indel: Indel) -> lsp_types::TextEdit {
     let range = range(line_index, indel.delete);
-    let new_text = match line_endings {
+    let new_text = match line_index.endings {
         LineEndings::Unix => indel.insert,
         LineEndings::Dos => indel.insert.replace('\n', "\r\n"),
     };
@@ -138,11 +135,10 @@ pub(crate) fn text_edit(
 
 pub(crate) fn snippet_text_edit(
     line_index: &LineIndex,
-    line_endings: LineEndings,
     is_snippet: bool,
     indel: Indel,
 ) -> lsp_ext::SnippetTextEdit {
-    let text_edit = text_edit(line_index, line_endings, indel);
+    let text_edit = text_edit(line_index, indel);
     let insert_text_format =
         if is_snippet { Some(lsp_types::InsertTextFormat::Snippet) } else { None };
     lsp_ext::SnippetTextEdit {
@@ -154,27 +150,24 @@ pub(crate) fn snippet_text_edit(
 
 pub(crate) fn text_edit_vec(
     line_index: &LineIndex,
-    line_endings: LineEndings,
     text_edit: TextEdit,
 ) -> Vec<lsp_types::TextEdit> {
-    text_edit.into_iter().map(|indel| self::text_edit(line_index, line_endings, indel)).collect()
+    text_edit.into_iter().map(|indel| self::text_edit(line_index, indel)).collect()
 }
 
 pub(crate) fn snippet_text_edit_vec(
     line_index: &LineIndex,
-    line_endings: LineEndings,
     is_snippet: bool,
     text_edit: TextEdit,
 ) -> Vec<lsp_ext::SnippetTextEdit> {
     text_edit
         .into_iter()
-        .map(|indel| self::snippet_text_edit(line_index, line_endings, is_snippet, indel))
+        .map(|indel| self::snippet_text_edit(line_index, is_snippet, indel))
         .collect()
 }
 
 pub(crate) fn completion_item(
     line_index: &LineIndex,
-    line_endings: LineEndings,
     completion_item: CompletionItem,
 ) -> Vec<lsp_types::CompletionItem> {
     fn set_score(res: &mut lsp_types::CompletionItem, label: &str) {
@@ -191,19 +184,19 @@ pub(crate) fn completion_item(
     for indel in completion_item.text_edit().iter() {
         if indel.delete.contains_range(source_range) {
             text_edit = Some(if indel.delete == source_range {
-                self::text_edit(line_index, line_endings, indel.clone())
+                self::text_edit(line_index, indel.clone())
             } else {
                 assert!(source_range.end() == indel.delete.end());
                 let range1 = TextRange::new(indel.delete.start(), source_range.start());
                 let range2 = source_range;
                 let indel1 = Indel::replace(range1, String::new());
                 let indel2 = Indel::replace(range2, indel.insert.clone());
-                additional_text_edits.push(self::text_edit(line_index, line_endings, indel1));
-                self::text_edit(line_index, line_endings, indel2)
+                additional_text_edits.push(self::text_edit(line_index, indel1));
+                self::text_edit(line_index, indel2)
             })
         } else {
             assert!(source_range.intersect(indel.delete).is_none());
-            let text_edit = self::text_edit(line_index, line_endings, indel.clone());
+            let text_edit = self::text_edit(line_index, indel.clone());
             additional_text_edits.push(text_edit);
         }
     }
@@ -359,7 +352,7 @@ pub(crate) fn semantic_tokens(
         let token_index = semantic_tokens::type_index(type_);
         let modifier_bitset = mods.0;
 
-        for mut text_range in line_index.lines(highlight_range.range) {
+        for mut text_range in line_index.index.lines(highlight_range.range) {
             if text[text_range].ends_with('\n') {
                 text_range =
                     TextRange::new(text_range.start(), text_range.end() - TextSize::of('\n'));
@@ -566,7 +559,7 @@ pub(crate) fn location(
     frange: FileRange,
 ) -> Result<lsp_types::Location> {
     let url = url(snap, frange.file_id);
-    let line_index = snap.analysis.file_line_index(frange.file_id)?;
+    let line_index = snap.file_line_index(frange.file_id)?;
     let range = range(&line_index, frange.range);
     let loc = lsp_types::Location::new(url, range);
     Ok(loc)
@@ -578,7 +571,7 @@ pub(crate) fn location_from_nav(
     nav: NavigationTarget,
 ) -> Result<lsp_types::Location> {
     let url = url(snap, nav.file_id);
-    let line_index = snap.analysis.file_line_index(nav.file_id)?;
+    let line_index = snap.file_line_index(nav.file_id)?;
     let range = range(&line_index, nav.full_range);
     let loc = lsp_types::Location::new(url, range);
     Ok(loc)
@@ -591,7 +584,7 @@ pub(crate) fn location_link(
 ) -> Result<lsp_types::LocationLink> {
     let origin_selection_range = match src {
         Some(src) => {
-            let line_index = snap.analysis.file_line_index(src.file_id)?;
+            let line_index = snap.file_line_index(src.file_id)?;
             let range = range(&line_index, src.range);
             Some(range)
         }
@@ -611,7 +604,7 @@ fn location_info(
     snap: &GlobalStateSnapshot,
     target: NavigationTarget,
 ) -> Result<(lsp_types::Url, lsp_types::Range, lsp_types::Range)> {
-    let line_index = snap.analysis.file_line_index(target.file_id)?;
+    let line_index = snap.file_line_index(target.file_id)?;
 
     let target_uri = url(snap, target.file_id);
     let target_range = range(&line_index, target.full_range);
@@ -649,12 +642,8 @@ pub(crate) fn snippet_text_document_edit(
     edit: TextEdit,
 ) -> Result<lsp_ext::SnippetTextDocumentEdit> {
     let text_document = optional_versioned_text_document_identifier(snap, file_id);
-    let line_index = snap.analysis.file_line_index(file_id)?;
-    let line_endings = snap.file_line_endings(file_id);
-    let edits = edit
-        .into_iter()
-        .map(|it| snippet_text_edit(&line_index, line_endings, is_snippet, it))
-        .collect();
+    let line_index = snap.file_line_index(file_id)?;
+    let edits = edit.into_iter().map(|it| snippet_text_edit(&line_index, is_snippet, it)).collect();
     Ok(lsp_ext::SnippetTextDocumentEdit { text_document, edits })
 }
 
@@ -675,9 +664,8 @@ pub(crate) fn snippet_text_document_ops(
             if !initial_contents.is_empty() {
                 let text_document =
                     lsp_types::OptionalVersionedTextDocumentIdentifier { uri, version: None };
-                let range = range(&LineIndex::new(""), TextRange::empty(TextSize::from(0)));
                 let text_edit = lsp_ext::SnippetTextEdit {
-                    range,
+                    range: lsp_types::Range::default(),
                     new_text: initial_contents,
                     insert_text_format: Some(lsp_types::InsertTextFormat::PlainText),
                 };
@@ -868,7 +856,7 @@ pub(crate) fn code_lens(
 ) -> Result<lsp_types::CodeLens> {
     match annotation.kind {
         AnnotationKind::Runnable { debug, runnable: run } => {
-            let line_index = snap.analysis.file_line_index(run.nav.file_id)?;
+            let line_index = snap.file_line_index(run.nav.file_id)?;
             let annotation_range = range(&line_index, annotation.range);
 
             let action = run.action();
@@ -884,7 +872,7 @@ pub(crate) fn code_lens(
             Ok(lsp_types::CodeLens { range: annotation_range, command: Some(command), data: None })
         }
         AnnotationKind::HasImpls { position: file_position, data } => {
-            let line_index = snap.analysis.file_line_index(file_position.file_id)?;
+            let line_index = snap.file_line_index(file_position.file_id)?;
             let annotation_range = range(&line_index, annotation.range);
             let url = url(snap, file_position.file_id);
 
@@ -927,7 +915,7 @@ pub(crate) fn code_lens(
             })
         }
         AnnotationKind::HasReferences { position: file_position, data } => {
-            let line_index = snap.analysis.file_line_index(file_position.file_id)?;
+            let line_index = snap.file_line_index(file_position.file_id)?;
             let annotation_range = range(&line_index, annotation.range);
             let url = url(snap, file_position.file_id);
 
@@ -1061,6 +1049,8 @@ pub(crate) fn rename_error(err: RenameError) -> crate::LspError {
 
 #[cfg(test)]
 mod tests {
+    use std::sync::Arc;
+
     use hir::PrefixKind;
     use ide::Analysis;
     use ide_db::helpers::{insert_use::InsertUseConfig, SnippetCap};
@@ -1078,7 +1068,8 @@ mod tests {
         }"#;
 
         let (offset, text) = test_utils::extract_offset(fixture);
-        let line_index = LineIndex::new(&text);
+        let line_index =
+            LineIndex { index: Arc::new(ide::LineIndex::new(&text)), endings: LineEndings::Unix };
         let (analysis, file_id) = Analysis::from_single_file(text);
         let completions: Vec<(String, Option<String>)> = analysis
             .completions(
@@ -1096,7 +1087,7 @@ mod tests {
             .unwrap()
             .into_iter()
             .filter(|c| c.label().ends_with("arg"))
-            .map(|c| completion_item(&line_index, LineEndings::Unix, c))
+            .map(|c| completion_item(&line_index, c))
             .flat_map(|comps| comps.into_iter().map(|c| (c.label, c.sort_text)))
             .collect();
         expect_test::expect![[r#"
@@ -1134,7 +1125,8 @@ fn main() {
         let folds = analysis.folding_ranges(file_id).unwrap();
         assert_eq!(folds.len(), 4);
 
-        let line_index = LineIndex::new(&text);
+        let line_index =
+            LineIndex { index: Arc::new(ide::LineIndex::new(&text)), endings: LineEndings::Unix };
         let converted: Vec<lsp_types::FoldingRange> =
             folds.into_iter().map(|it| folding_range(&text, &line_index, true, it)).collect();