separate the Collector from the Data it is collecting

Author: nikomatsakis

src/librustc/infer/lexical_region_resolve/graphviz.rs

@@ -25,7 +25,7 @@ use middle::free_region::RegionRelations;
 use middle::region;
 use super::Constraint;
 use infer::SubregionOrigin;
-use infer::region_constraints::RegionConstraintCollector;
+use infer::region_constraints::RegionConstraintData;
 use util::nodemap::{FxHashMap, FxHashSet};
 
 use std::borrow::Cow;
@@ -57,7 +57,7 @@ graphs will be printed.                                                     \n\
 }
 
 pub fn maybe_print_constraints_for<'a, 'gcx, 'tcx>(
-    region_constraints: &RegionConstraintCollector<'tcx>,
+    region_data: &RegionConstraintData<'tcx>,
     region_rels: &RegionRelations<'a, 'gcx, 'tcx>)
 {
     let tcx = region_rels.tcx;
@@ -113,7 +113,7 @@ pub fn maybe_print_constraints_for<'a, 'gcx, 'tcx>(
         }
     };
 
-    match dump_region_constraints_to(region_rels, &region_constraints.constraints, &output_path) {
+    match dump_region_data_to(region_rels, &region_data.constraints, &output_path) {
         Ok(()) => {}
         Err(e) => {
             let msg = format!("io error dumping region constraints: {}", e);
@@ -267,15 +267,15 @@ impl<'a, 'gcx, 'tcx> dot::GraphWalk<'a> for ConstraintGraph<'a, 'gcx, 'tcx> {
 
 pub type ConstraintMap<'tcx> = BTreeMap<Constraint<'tcx>, SubregionOrigin<'tcx>>;
 
-fn dump_region_constraints_to<'a, 'gcx, 'tcx>(region_rels: &RegionRelations<'a, 'gcx, 'tcx>,
-                                              map: &ConstraintMap<'tcx>,
-                                              path: &str)
-                                              -> io::Result<()> {
-    debug!("dump_region_constraints map (len: {}) path: {}",
+fn dump_region_data_to<'a, 'gcx, 'tcx>(region_rels: &RegionRelations<'a, 'gcx, 'tcx>,
+                                       map: &ConstraintMap<'tcx>,
+                                       path: &str)
+                                       -> io::Result<()> {
+    debug!("dump_region_data map (len: {}) path: {}",
            map.len(),
            path);
-    let g = ConstraintGraph::new(format!("region_constraints"), region_rels, map);
-    debug!("dump_region_constraints calling render");
+    let g = ConstraintGraph::new(format!("region_data"), region_rels, map);
+    debug!("dump_region_data calling render");
     let mut v = Vec::new();
     dot::render(&g, &mut v).unwrap();
     File::create(path).and_then(|mut f| f.write_all(&v))

src/librustc/infer/lexical_region_resolve/mod.rs

@@ -14,7 +14,7 @@ use infer::SubregionOrigin;
 use infer::RegionVariableOrigin;
 use infer::region_constraints::Constraint;
 use infer::region_constraints::GenericKind;
-use infer::region_constraints::RegionConstraintCollector;
+use infer::region_constraints::RegionConstraintData;
 use infer::region_constraints::VerifyBound;
 use middle::free_region::RegionRelations;
 use rustc_data_structures::fx::FxHashSet;
@@ -73,20 +73,20 @@ struct RegionAndOrigin<'tcx> {
 
 type RegionGraph<'tcx> = graph::Graph<(), Constraint<'tcx>>;
 
-impl<'tcx> RegionConstraintCollector<'tcx> {
+impl<'tcx> RegionConstraintData<'tcx> {
     /// This function performs the actual region resolution.  It must be
     /// called after all constraints have been added.  It performs a
     /// fixed-point iteration to find region values which satisfy all
     /// constraints, assuming such values can be found; if they cannot,
     /// errors are reported.
     pub fn resolve_regions(
-        &mut self,
+        mut self,
         region_rels: &RegionRelations<'_, '_, 'tcx>,
     ) -> (
         LexicalRegionResolutions<'tcx>,
         Vec<RegionResolutionError<'tcx>>,
     ) {
-        debug!("RegionConstraintCollector: resolve_regions()");
+        debug!("RegionConstraintData: resolve_regions()");
         let mut errors = vec![];
         let values = self.infer_variable_values(region_rels, &mut errors);
         (values, errors)
@@ -642,7 +642,7 @@ impl<'tcx> RegionConstraintCollector<'tcx> {
         return (result, dup_found);
 
         fn process_edges<'tcx>(
-            this: &RegionConstraintCollector<'tcx>,
+            this: &RegionConstraintData<'tcx>,
             state: &mut WalkState<'tcx>,
             graph: &RegionGraph<'tcx>,
             source_vid: RegionVid,

src/librustc/infer/mod.rs

@@ -1132,10 +1132,11 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
                                                region_context,
                                                region_map,
                                                free_regions);
-        let mut region_constraints = self.region_constraints.borrow_mut()
-                                                            .take()
-                                                            .expect("regions already resolved");
-        let (lexical_region_resolutions, errors) = region_constraints.resolve_regions(&region_rels);
+        let region_data = self.region_constraints.borrow_mut()
+                                                 .take()
+                                                 .expect("regions already resolved")
+                                                 .into_data();
+        let (lexical_region_resolutions, errors) = region_data.resolve_regions(&region_rels);
 
         let old_value = self.lexical_region_resolutions.replace(Some(lexical_region_resolutions));
         assert!(old_value.is_none());