perf: Remove spurious allocations (toml-rs#212)

epage · Sep 24, 2021 · 41b4527 · 41b4527
1 parent 1f81d2e
commit 41b4527
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Showing 2 changed files with 10 additions and 9 deletions.
diff --git a/src/index.rs b/src/index.rs
@@ -56,24 +56,23 @@ impl Index for str {
         }
     }
     fn index_or_insert<'v>(&self, v: &'v mut Item) -> &'v mut Item {
-        let key = Key::new(self);
         if let Item::None = *v {
             let mut t = InlineTable::default();
             t.items.insert(
-                InternalString::from(key.get()),
-                TableKeyValue::new(key.clone(), Item::None),
+                InternalString::from(self),
+                TableKeyValue::new(Key::new(self), Item::None),
             );
             *v = value(Value::InlineTable(t));
         }
         match *v {
-            Item::Table(ref mut t) => t.entry(key.get()).or_insert(Item::None),
+            Item::Table(ref mut t) => t.entry(self).or_insert(Item::None),
             Item::Value(ref mut v) if v.is_inline_table() => {
                 &mut v
                     .as_inline_table_mut()
                     .unwrap()
                     .items
-                    .entry(InternalString::from(key.get()))
-                    .or_insert(TableKeyValue::new(key, Item::None))
+                    .entry(InternalString::from(self))
+                    .or_insert_with(|| TableKeyValue::new(Key::new(self), Item::None))
                     .value
             }
             _ => panic!("cannot access key {}", self),

diff --git a/src/parser/inline_table.rs b/src/parser/inline_table.rs
@@ -24,6 +24,8 @@ fn table_from_pairs(
 ) -> Result<InlineTable, CustomError> {
     let mut root = InlineTable::new();
     root.preamble = InternalString::from(preamble);
+    // Assuming almost all pairs will be directly in `root`
+    root.items.reserve(v.len());
 
     for (path, kv) in v {
         let table = descend_path(&mut root, &path, 0)?;
@@ -33,7 +35,7 @@ fn table_from_pairs(
                 table: "inline".into(),
             });
         }
-        table.items.insert(kv.key.clone().into(), kv);
+        table.items.insert(kv.key.get().into(), kv);
     }
     Ok(root)
 }
@@ -88,8 +90,8 @@ parse!(keyval() -> (Vec<Key>, TableKeyValue), {
         char(KEYVAL_SEP),
         (ws(), value(), ws()),
     ).map(|(key, _, v)| {
-            let mut path = key.into_vec();
-            let key = path.pop().expect("Was vec1, so at least one exists");
+        let mut path = key.into_vec();
+        let key = path.pop().expect("Was vec1, so at least one exists");
 
         let (pre, v, suf) = v;
         let v = v.decorated(pre, suf);