Support deserializing bool in map keys

Author: dtolnay

src/de.rs

@@ -2203,6 +2203,41 @@ where
     deserialize_numeric_key!(deserialize_f32, deserialize_f32);
     deserialize_numeric_key!(deserialize_f64);
 
+    fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        self.de.eat_char();
+
+        let peek = match tri!(self.de.next_char()) {
+            Some(b) => b,
+            None => {
+                return Err(self.de.peek_error(ErrorCode::EofWhileParsingValue));
+            }
+        };
+
+        let value = match peek {
+            b't' => {
+                tri!(self.de.parse_ident(b"rue\""));
+                visitor.visit_bool(true)
+            }
+            b'f' => {
+                tri!(self.de.parse_ident(b"alse\""));
+                visitor.visit_bool(false)
+            }
+            _ => {
+                self.de.scratch.clear();
+                let s = tri!(self.de.read.parse_str(&mut self.de.scratch));
+                Err(de::Error::invalid_type(Unexpected::Str(&s), &visitor))
+            }
+        };
+
+        match value {
+            Ok(value) => Ok(value),
+            Err(err) => Err(self.de.fix_position(err)),
+        }
+    }
+
     #[inline]
     fn deserialize_option<V>(self, visitor: V) -> Result<V::Value>
     where
@@ -2258,7 +2293,7 @@ where
     }
 
     forward_to_deserialize_any! {
-        bool char str string unit unit_struct seq tuple tuple_struct map struct
+        char str string unit unit_struct seq tuple tuple_struct map struct
         identifier ignored_any
     }
 }

src/value/de.rs

@@ -1183,6 +1183,22 @@ impl<'de> serde::Deserializer<'de> for MapKeyDeserializer<'de> {
     deserialize_numeric_key!(deserialize_i128, do_deserialize_i128);
     deserialize_numeric_key!(deserialize_u128, do_deserialize_u128);
 
+    fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Error>
+    where
+        V: Visitor<'de>,
+    {
+        if self.key == "true" {
+            visitor.visit_bool(true)
+        } else if self.key == "false" {
+            visitor.visit_bool(false)
+        } else {
+            Err(serde::de::Error::invalid_type(
+                Unexpected::Str(&self.key),
+                &visitor,
+            ))
+        }
+    }
+
     #[inline]
     fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Error>
     where
@@ -1219,8 +1235,8 @@ impl<'de> serde::Deserializer<'de> for MapKeyDeserializer<'de> {
     }
 
     forward_to_deserialize_any! {
-        bool char str string bytes byte_buf unit unit_struct seq tuple
-        tuple_struct map struct identifier ignored_any
+        char str string bytes byte_buf unit unit_struct seq tuple tuple_struct
+        map struct identifier ignored_any
     }
 }