Store dumper directly in Visitor

Author: Mark-Simulacrum

src/librustc_save_analysis/dump_visitor.rs

@@ -75,10 +75,10 @@ macro_rules! access_from_vis {
     };
 }
 
-pub struct DumpVisitor<'l, 'tcx, 'll> {
+pub struct DumpVisitor<'l, 'tcx> {
     save_ctxt: SaveContext<'l, 'tcx>,
     tcx: TyCtxt<'tcx>,
-    dumper: &'ll mut Dumper,
+    dumper: Dumper,
 
     span: SpanUtils<'l>,
 
@@ -90,12 +90,12 @@ pub struct DumpVisitor<'l, 'tcx, 'll> {
     // macro_calls: FxHashSet<Span>,
 }
 
-impl<'l, 'tcx, 'll> DumpVisitor<'l, 'tcx, 'll> {
+impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
     pub fn new(
         save_ctxt: SaveContext<'l, 'tcx>,
-        dumper: &'ll mut Dumper,
-    ) -> DumpVisitor<'l, 'tcx, 'll> {
+    ) -> DumpVisitor<'l, 'tcx> {
         let span_utils = SpanUtils::new(&save_ctxt.tcx.sess);
+        let dumper = Dumper::new(save_ctxt.config.clone());
         DumpVisitor {
             tcx: save_ctxt.tcx,
             save_ctxt,
@@ -106,9 +106,13 @@ impl<'l, 'tcx, 'll> DumpVisitor<'l, 'tcx, 'll> {
         }
     }
 
+    pub fn into_analysis(self) -> rls_data::Analysis {
+        self.dumper.into_analysis()
+    }
+
     fn nest_tables<F>(&mut self, item_id: NodeId, f: F)
     where
-        F: FnOnce(&mut DumpVisitor<'l, 'tcx, 'll>),
+        F: FnOnce(&mut Self),
     {
         let item_def_id = self.tcx.hir().local_def_id_from_node_id(item_id);
         if self.tcx.has_typeck_tables(item_def_id) {
@@ -1298,7 +1302,7 @@ impl<'l, 'tcx, 'll> DumpVisitor<'l, 'tcx, 'll> {
     }
 }
 
-impl<'l, 'tcx, 'll> Visitor<'l> for DumpVisitor<'l, 'tcx, 'll> {
+impl<'l, 'tcx> Visitor<'l> for DumpVisitor<'l, 'tcx> {
     fn visit_mod(&mut self, m: &'l ast::Mod, span: Span, attrs: &[ast::Attribute], id: NodeId) {
         // Since we handle explicit modules ourselves in visit_item, this should
         // only get called for the root module of a crate.

src/librustc_save_analysis/dumper.rs

@@ -22,8 +22,8 @@ impl Dumper {
         }
     }
 
-    pub fn to_output(self, f: impl FnOnce(&Analysis)) {
-        f(&self.result)
+    pub fn into_analysis(self) -> Analysis {
+        self.result
     }
 }
 

src/librustc_save_analysis/lib.rs

@@ -39,7 +39,6 @@ use syntax::visit::{self, Visitor};
 use syntax::print::pprust::{arg_to_string, ty_to_string};
 use syntax_pos::*;
 
-use dumper::Dumper;
 use dump_visitor::DumpVisitor;
 use span_utils::SpanUtils;
 
@@ -1076,18 +1075,15 @@ impl<'a> SaveHandler for DumpHandler<'a> {
     ) {
         let sess = &save_ctxt.tcx.sess;
         let (output, file_name) = self.output_file(&save_ctxt);
-        let mut dumper = Dumper::new(save_ctxt.config.clone());
-        let mut visitor = DumpVisitor::new(save_ctxt, &mut dumper);
+        let mut visitor = DumpVisitor::new(save_ctxt);
 
         visitor.dump_crate_info(cratename, krate);
         visitor.dump_compilation_options(input, cratename);
         visit::walk_crate(&mut visitor, krate);
 
-        dumper.to_output(|analysis| {
-            if let Err(e) = serde_json::to_writer(output, analysis) {
-                error!("Can't serialize save-analysis: {:?}", e);
-            }
-        });
+        if let Err(e) = serde_json::to_writer(output, &visitor.into_analysis()) {
+            error!("Can't serialize save-analysis: {:?}", e);
+        }
 
         if sess.opts.debugging_opts.emit_artifact_notifications {
             sess.parse_sess.span_diagnostic
@@ -1109,19 +1105,13 @@ impl<'b> SaveHandler for CallbackHandler<'b> {
         cratename: &str,
         input: &'l Input,
     ) {
-        // We're using the Dumper here because it has the format of the
-        // save-analysis results that we will pass to the callback. IOW, we are
-        // using the Dumper to collect the save-analysis results, but not
-        // actually to dump them to a file. This is all a bit convoluted and
-        // there is certainly a simpler design here trying to get out (FIXME).
-        let mut dumper = Dumper::new(save_ctxt.config.clone());
-        let mut visitor = DumpVisitor::new(save_ctxt, &mut dumper);
+        let mut visitor = DumpVisitor::new(save_ctxt);
 
         visitor.dump_crate_info(cratename, krate);
         visitor.dump_compilation_options(input, cratename);
         visit::walk_crate(&mut visitor, krate);
 
-        dumper.to_output(|a| (self.callback)(a))
+        (self.callback)(&visitor.into_analysis())
     }
 }