Use an indexmap in IdAliasStore

pierwill · pierwill · commit 537f869639c7 · 2021-12-17T11:38:33.000-06:00
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/chalk-solve/Cargo.toml b/chalk-solve/Cargo.toml
@@ -20,6 +20,7 @@ rustc-hash = { version = "1.1.0" }
 
 chalk-derive = { version = "0.76.0-dev.0", path = "../chalk-derive" }
 chalk-ir = { version = "0.76.0-dev.0", path = "../chalk-ir" }
+indexmap = "1.6.2"
 
 [dev-dependencies]
 chalk-integration = { path = "../chalk-integration" }
diff --git a/chalk-solve/src/display/state.rs b/chalk-solve/src/display/state.rs
@@ -46,15 +46,15 @@ enum UnifiedId<I: Interner> {
 pub struct IdAliasStore<T> {
     /// Map from the DefIds we've encountered to a u32 alias id unique to all ids
     /// the same name.
-    aliases: BTreeMap<T, u32>,
+    aliases: indexmap::IndexMap<T, u32>,
     /// Map from each name to the next unused u32 alias id.
     next_unused_for_name: BTreeMap<String, u32>,
 }
 
 impl<T> Default for IdAliasStore<T> {
     fn default() -> Self {
         IdAliasStore {
-            aliases: BTreeMap::default(),
+            aliases: indexmap::IndexMap::default(),
             next_unused_for_name: BTreeMap::default(),
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -46,15 +46,15 @@ enum UnifiedId<I: Interner> {`
`46`	`46`	`pub struct IdAliasStore<T> {`
`47`	`47`	`/// Map from the DefIds we've encountered to a u32 alias id unique to all ids`
`48`	`48`	`/// the same name.`
`49`		`- aliases: BTreeMap<T, u32>,`
	`49`	`+ aliases: indexmap::IndexMap<T, u32>,`
`50`	`50`	`/// Map from each name to the next unused u32 alias id.`
`51`	`51`	`next_unused_for_name: BTreeMap<String, u32>,`
`52`	`52`	`}`
`53`	`53`
`54`	`54`	`impl<T> Default for IdAliasStore<T> {`
`55`	`55`	`fn default() -> Self {`
`56`	`56`	`IdAliasStore {`
`57`		`- aliases: BTreeMap::default(),`
	`57`	`+ aliases: indexmap::IndexMap::default(),`
`58`	`58`	`next_unused_for_name: BTreeMap::default(),`
`59`	`59`	`}`
`60`	`60`	`}`