handling fallout from entry api

Author: Gankra

src/librustc/driver/config.rs

@@ -31,6 +31,7 @@ use syntax::parse;
 use syntax::parse::token::InternedString;
 
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use getopts::{optopt, optmulti, optflag, optflagopt};
 use getopts;
 use std::cell::{RefCell};
@@ -808,8 +809,11 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
             Some(s) => s,
             None => early_error("--extern value must be of the format `foo=bar`"),
         };
-        let locs = externs.find_or_insert(name.to_string(), Vec::new());
-        locs.push(location.to_string());
+
+        match externs.entry(name.to_string()) {
+            Vacant(entry) => { entry.set(vec![location.to_string()]); },
+            Occupied(mut entry) => { entry.get_mut().push(location.to_string()); },
+        }
     }
 
     let crate_name = matches.opt_str("crate-name");

src/librustc/lint/builtin.rs

@@ -36,6 +36,7 @@ use lint::{Context, LintPass, LintArray};
 
 use std::cmp;
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use std::slice;
 use std::{i8, i16, i32, i64, u8, u16, u32, u64, f32, f64};
 use syntax::abi;
@@ -1204,15 +1205,18 @@ impl UnusedMut {
     fn check_unused_mut_pat(&self, cx: &Context, pats: &[P<ast::Pat>]) {
         // collect all mutable pattern and group their NodeIDs by their Identifier to
         // avoid false warnings in match arms with multiple patterns
+
         let mut mutables = HashMap::new();
         for p in pats.iter() {
             pat_util::pat_bindings(&cx.tcx.def_map, &**p, |mode, id, _, path1| {
                 let ident = path1.node;
                 match mode {
                     ast::BindByValue(ast::MutMutable) => {
                         if !token::get_ident(ident).get().starts_with("_") {
-                            mutables.insert_or_update_with(ident.name.uint(),
-                                vec!(id), |_, old| { old.push(id); });
+                            match mutables.entry(ident.name.uint()) {
+                                Vacant(entry) => { entry.set(vec![id]); },
+                                Occupied(mut entry) => { entry.get_mut().push(id); },
+                            }
                         }
                     }
                     _ => {

src/librustc/metadata/creader.rs

@@ -24,6 +24,7 @@ use plugin::load::PluginMetadata;
 
 use std::rc::Rc;
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use syntax::ast;
 use syntax::abi;
 use syntax::attr;
@@ -82,7 +83,10 @@ fn dump_crates(cstore: &CStore) {
 fn warn_if_multiple_versions(diag: &SpanHandler, cstore: &CStore) {
     let mut map = HashMap::new();
     cstore.iter_crate_data(|cnum, data| {
-        map.find_or_insert_with(data.name(), |_| Vec::new()).push(cnum);
+        match map.entry(data.name()) {
+            Vacant(entry) => { entry.set(vec![cnum]); },
+            Occupied(mut entry) => { entry.get_mut().push(cnum); },
+        }
     });
 
     for (name, dupes) in map.into_iter() {

src/librustc/metadata/loader.rs

@@ -237,6 +237,7 @@ use std::slice;
 use std::string;
 
 use std::collections::{HashMap, HashSet};
+use std::collections::hashmap::{Occupied, Vacant};
 use flate;
 use time;
 
@@ -428,15 +429,18 @@ impl<'a> Context<'a> {
                 return FileDoesntMatch
             };
             info!("lib candidate: {}", path.display());
-            let slot = candidates.find_or_insert_with(hash.to_string(), |_| {
-                (HashSet::new(), HashSet::new())
-            });
+
+            let slot = match candidates.entry(hash.to_string()) {
+                Occupied(entry) => entry.into_mut(),
+                Vacant(entry) => entry.set((HashSet::new(), HashSet::new())),
+            };
             let (ref mut rlibs, ref mut dylibs) = *slot;
             if rlib {
                 rlibs.insert(fs::realpath(path).unwrap());
             } else {
                 dylibs.insert(fs::realpath(path).unwrap());
             }
+
             FileMatches
         });
 

src/librustc/middle/const_eval.rs

@@ -28,6 +28,7 @@ use syntax::visit;
 use syntax::{ast, ast_map, ast_util};
 
 use std::rc::Rc;
+use std::collections::hashmap::Vacant;
 
 //
 // This pass classifies expressions by their constant-ness.
@@ -321,7 +322,10 @@ pub fn const_expr_to_pat(tcx: &ty::ctxt, expr: &Expr) -> P<Pat> {
 
         ExprCall(ref callee, ref args) => {
             let def = tcx.def_map.borrow().get_copy(&callee.id);
-            tcx.def_map.borrow_mut().find_or_insert(expr.id, def);
+            match tcx.def_map.borrow_mut().entry(expr.id) {
+              Vacant(entry) => { entry.set(def); }
+              _ => {}
+            };
             let path = match def {
                 def::DefStruct(def_id) => def_to_path(tcx, def_id),
                 def::DefVariant(_, variant_did, _) => def_to_path(tcx, variant_did),

src/librustc/middle/resolve.rs

@@ -58,6 +58,7 @@ use syntax::visit;
 use syntax::visit::Visitor;
 
 use std::collections::{HashMap, HashSet};
+use std::collections::hashmap::{Occupied, Vacant};
 use std::cell::{Cell, RefCell};
 use std::gc::GC;
 use std::mem::replace;
@@ -2813,10 +2814,13 @@ impl<'a> Resolver<'a> {
         let is_public = import_directive.is_public;
 
         let mut import_resolutions = module_.import_resolutions.borrow_mut();
-        let dest_import_resolution = import_resolutions.find_or_insert_with(name, |_| {
-            // Create a new import resolution from this child.
-            ImportResolution::new(id, is_public)
-        });
+        let dest_import_resolution = match import_resolutions.entry(name) {
+            Occupied(entry) => entry.into_mut(),
+            Vacant(entry) => {
+                // Create a new import resolution from this child.
+                entry.set(ImportResolution::new(id, is_public))
+            }
+        };
 
         debug!("(resolving glob import) writing resolution `{}` in `{}` \
                to `{}`",
@@ -5991,19 +5995,21 @@ impl<'a> Resolver<'a> {
         assert!(match lp {LastImport{..} => false, _ => true},
                 "Import should only be used for `use` directives");
         self.last_private.insert(node_id, lp);
-        self.def_map.borrow_mut().insert_or_update_with(node_id, def, |_, old_value| {
+
+        match self.def_map.borrow_mut().entry(node_id) {
             // Resolve appears to "resolve" the same ID multiple
             // times, so here is a sanity check it at least comes to
             // the same conclusion! - nmatsakis
-            if def != *old_value {
+            Occupied(entry) => if def != *entry.get() {
                 self.session
                     .bug(format!("node_id {:?} resolved first to {:?} and \
                                   then {:?}",
                                  node_id,
-                                 *old_value,
+                                 *entry.get(),
                                  def).as_slice());
-            }
-        });
+            },
+            Vacant(entry) => { entry.set(def); },
+        }
     }
 
     fn enforce_default_binding_mode(&mut self,

src/librustc/middle/ty.rs

@@ -50,6 +50,7 @@ use std::mem;
 use std::ops;
 use std::rc::Rc;
 use std::collections::{HashMap, HashSet};
+use std::collections::hashmap::{Occupied, Vacant};
 use arena::TypedArena;
 use syntax::abi;
 use syntax::ast::{CrateNum, DefId, FnStyle, Ident, ItemTrait, LOCAL_CRATE};
@@ -4641,9 +4642,10 @@ pub fn lookup_field_type(tcx: &ctxt,
         node_id_to_type(tcx, id.node)
     } else {
         let mut tcache = tcx.tcache.borrow_mut();
-        let pty = tcache.find_or_insert_with(id, |_| {
-            csearch::get_field_type(tcx, struct_id, id)
-        });
+        let pty = match tcache.entry(id) {
+            Occupied(entry) => entry.into_mut(),
+            Vacant(entry) => entry.set(csearch::get_field_type(tcx, struct_id, id)),
+        };
         pty.ty
     };
     t.subst(tcx, substs)

src/librustc/middle/typeck/check/mod.rs

@@ -122,6 +122,7 @@ use util::nodemap::{DefIdMap, FnvHashMap, NodeMap};
 
 use std::cell::{Cell, RefCell};
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use std::mem::replace;
 use std::rc::Rc;
 use std::slice;
@@ -2017,11 +2018,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
          */
 
         let mut region_obligations = self.inh.region_obligations.borrow_mut();
-        let v = region_obligations.find_or_insert_with(self.body_id,
-                                                       |_| Vec::new());
-        v.push(RegionObligation { sub_region: r,
+        let region_obligation = RegionObligation { sub_region: r,
                                   sup_type: ty,
-                                  origin: origin });
+                                  origin: origin };
+
+        match region_obligations.entry(self.body_id) {
+            Vacant(entry) => { entry.set(vec![region_obligation]); },
+            Occupied(mut entry) => { entry.get_mut().push(region_obligation); },
+        }
     }
 
     pub fn add_obligations_for_parameters(&self,

src/librustc/middle/typeck/check/regionmanip.rs

@@ -18,6 +18,7 @@ use middle::ty_fold::TypeFolder;
 use syntax::ast;
 
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use util::ppaux::Repr;
 
 // Helper functions related to manipulating region types.
@@ -35,7 +36,10 @@ pub fn replace_late_bound_regions_in_fn_sig(
             debug!("region r={}", r.to_string());
             match r {
                 ty::ReLateBound(s, br) if s == fn_sig.binder_id => {
-                    *map.find_or_insert_with(br, |_| mapf(br))
+                    * match map.entry(br) {
+                        Vacant(entry) => entry.set(mapf(br)),
+                        Occupied(entry) => entry.into_mut(),
+                    }
                 }
                 _ => r
             }

src/librustdoc/html/render.rs

@@ -34,6 +34,7 @@
 //! both occur before the crate is rendered.
 
 use std::collections::{HashMap, HashSet};
+use std::collections::hashmap::{Occupied, Vacant};
 use std::fmt;
 use std::io::fs::PathExtensions;
 use std::io::{fs, File, BufferedWriter, MemWriter, BufferedReader};
@@ -801,9 +802,10 @@ impl DocFolder for Cache {
             clean::ImplItem(ref i) => {
                 match i.trait_ {
                     Some(clean::ResolvedPath{ did, .. }) => {
-                        let v = self.implementors.find_or_insert_with(did, |_| {
-                            Vec::new()
-                        });
+                        let v = match self.implementors.entry(did) {
+                            Vacant(entry) => entry.set(Vec::with_capacity(1)),
+                            Occupied(entry) => entry.into_mut(),
+                        };
                         v.push(Implementor {
                             def_id: item.def_id,
                             generics: i.generics.clone(),
@@ -998,9 +1000,10 @@ impl DocFolder for Cache {
 
                         match did {
                             Some(did) => {
-                                let v = self.impls.find_or_insert_with(did, |_| {
-                                    Vec::new()
-                                });
+                                let v = match self.impls.entry(did) {
+                                    Vacant(entry) => entry.set(Vec::with_capacity(1)),
+                                    Occupied(entry) => entry.into_mut(),
+                                };
                                 v.push(Impl {
                                     impl_: i,
                                     dox: dox,
@@ -2141,7 +2144,10 @@ fn build_sidebar(m: &clean::Module) -> HashMap<String, Vec<String>> {
             None => continue,
             Some(ref s) => s.to_string(),
         };
-        let v = map.find_or_insert_with(short.to_string(), |_| Vec::new());
+        let v = match map.entry(short.to_string()) {
+            Vacant(entry) => entry.set(Vec::with_capacity(1)),
+            Occupied(entry) => entry.into_mut(),
+        };
         v.push(myname);
     }
 

src/librustdoc/lib.rs

@@ -31,6 +31,7 @@ extern crate time;
 use std::io;
 use std::io::{File, MemWriter};
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use serialize::{json, Decodable, Encodable};
 use externalfiles::ExternalHtml;
 
@@ -340,7 +341,10 @@ fn parse_externs(matches: &getopts::Matches) -> Result<core::Externs, String> {
                 return Err("--extern value must be of the format `foo=bar`".to_string());
             }
         };
-        let locs = externs.find_or_insert(name.to_string(), Vec::new());
+        let locs = match externs.entry(name.to_string()) {
+            Vacant(entry) => entry.set(Vec::with_capacity(1)),
+            Occupied(entry) => entry.into_mut(),
+        };
         locs.push(location.to_string());
     }
     Ok(externs)

src/libsyntax/ext/mtwt.rs

@@ -20,6 +20,7 @@ use ast::{Ident, Mrk, Name, SyntaxContext};
 use std::cell::RefCell;
 use std::rc::Rc;
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 
 /// The SCTable contains a table of SyntaxContext_'s. It
 /// represents a flattened tree structure, to avoid having
@@ -65,10 +66,10 @@ pub fn apply_mark(m: Mrk, ctxt: SyntaxContext) -> SyntaxContext {
 /// Extend a syntax context with a given mark and sctable (explicit memoization)
 fn apply_mark_internal(m: Mrk, ctxt: SyntaxContext, table: &SCTable) -> SyntaxContext {
     let key = (ctxt, m);
-    let new_ctxt = |_: &(SyntaxContext, Mrk)|
-                   idx_push(&mut *table.table.borrow_mut(), Mark(m, ctxt));
-
-    *table.mark_memo.borrow_mut().find_or_insert_with(key, new_ctxt)
+    * match table.mark_memo.borrow_mut().entry(key) {
+        Vacant(entry) => entry.set(idx_push(&mut *table.table.borrow_mut(), Mark(m, ctxt))),
+        Occupied(entry) => entry.into_mut(),
+    }
 }
 
 /// Extend a syntax context with a given rename
@@ -83,10 +84,11 @@ fn apply_rename_internal(id: Ident,
                        ctxt: SyntaxContext,
                        table: &SCTable) -> SyntaxContext {
     let key = (ctxt, id, to);
-    let new_ctxt = |_: &(SyntaxContext, Ident, Name)|
-                   idx_push(&mut *table.table.borrow_mut(), Rename(id, to, ctxt));
 
-    *table.rename_memo.borrow_mut().find_or_insert_with(key, new_ctxt)
+    * match table.rename_memo.borrow_mut().entry(key) {
+        Vacant(entry) => entry.set(idx_push(&mut *table.table.borrow_mut(), Rename(id, to, ctxt))),
+        Occupied(entry) => entry.into_mut(),
+    }
 }
 
 /// Apply a list of renamings to a context

src/libtest/stats.rs

@@ -11,6 +11,7 @@
 #![allow(missing_doc)]
 
 use std::collections::hashmap;
+use std::collections::hashmap::{Occupied, Vacant};
 use std::fmt::Show;
 use std::hash::Hash;
 use std::io;
@@ -443,7 +444,10 @@ pub fn write_boxplot<T: Float + Show + FromPrimitive>(
 pub fn freq_count<T: Iterator<U>, U: Eq+Hash>(mut iter: T) -> hashmap::HashMap<U, uint> {
     let mut map: hashmap::HashMap<U,uint> = hashmap::HashMap::new();
     for elem in iter {
-        map.insert_or_update_with(elem, 1, |_, count| *count += 1);
+        match map.entry(elem) {
+            Occupied(mut entry) => { *entry.get_mut() += 1; },
+            Vacant(entry) => { entry.set(1); },
+        }
     }
     map
 }

src/liburl/lib.rs

@@ -23,6 +23,7 @@
 #![feature(default_type_params)]
 
 use std::collections::HashMap;
+use std::collections::hashmap::{Occupied, Vacant};
 use std::fmt;
 use std::from_str::FromStr;
 use std::hash;
@@ -342,8 +343,10 @@ pub fn decode_form_urlencoded(s: &[u8])
                         key: String,
                         value: String) {
         if key.len() > 0 && value.len() > 0 {
-            let values = map.find_or_insert_with(key, |_| vec!());
-            values.push(value);
+            match map.entry(key) {
+                Vacant(entry) => { entry.set(vec![value]); },
+                Occupied(mut entry) => { entry.get_mut().push(value); },
+            }
         }
     }