benchmark and improve method parsing

amqp_transport/src/methods/mod.rs

@@ -1,4 +1,5 @@
 use crate::error::{ConException, TransError};
+use rand::Rng;
 use std::collections::HashMap;
 
 mod generated;
@@ -56,3 +57,70 @@ pub fn parse_method(payload: &[u8]) -> Result<generated::Method, TransError> {
         Err(nom::Err::Failure(err) | nom::Err::Error(err)) => Err(err),
     }
 }
+
+/// Allows the creation of a random instance of that type
+pub trait RandomMethod<R: Rng> {
+    fn random(rng: &mut R) -> Self;
+}
+
+impl<R: Rng> RandomMethod<R> for String {
+    fn random(rng: &mut R) -> Self {
+        let n = rng.gen_range(0_u16..9999);
+        format!("string{n}")
+    }
+}
+
+impl<R: Rng, T: RandomMethod<R>> RandomMethod<R> for Vec<T> {
+    fn random(rng: &mut R) -> Self {
+        let len = rng.gen_range(1_usize..10);
+        let mut vec = Vec::with_capacity(len);
+        (0..len).for_each(|_| vec.push(RandomMethod::random(rng)));
+        vec
+    }
+}
+
+macro_rules! rand_random_method {
+    ($($ty:ty),+) => {
+        $(
+             impl<R: Rng> RandomMethod<R> for $ty {
+             fn random(rng: &mut R) -> Self {
+                rng.gen()
+            }
+        })+
+    };
+}
+
+rand_random_method!(bool, u8, i8, u16, i16, u32, i32, u64, i64, f32, f64);
+
+impl<R: Rng> RandomMethod<R> for HashMap<String, FieldValue> {
+    fn random(rng: &mut R) -> Self {
+        let len = rng.gen_range(0..3);
+        HashMap::from_iter((0..len).map(|_| (String::random(rng), FieldValue::random(rng))))
+    }
+}
+
+impl<R: Rng> RandomMethod<R> for FieldValue {
+    fn random(rng: &mut R) -> Self {
+        let index = rng.gen_range(0_u32..17);
+        match index {
+            0 => FieldValue::Boolean(RandomMethod::random(rng)),
+            1 => FieldValue::ShortShortInt(RandomMethod::random(rng)),
+            2 => FieldValue::ShortShortUInt(RandomMethod::random(rng)),
+            3 => FieldValue::ShortInt(RandomMethod::random(rng)),
+            4 => FieldValue::ShortUInt(RandomMethod::random(rng)),
+            5 => FieldValue::LongInt(RandomMethod::random(rng)),
+            6 => FieldValue::LongUInt(RandomMethod::random(rng)),
+            7 => FieldValue::LongLongInt(RandomMethod::random(rng)),
+            8 => FieldValue::LongLongUInt(RandomMethod::random(rng)),
+            9 => FieldValue::Float(RandomMethod::random(rng)),
+            10 => FieldValue::Double(RandomMethod::random(rng)),
+            11 => FieldValue::ShortString(RandomMethod::random(rng)),
+            12 => FieldValue::LongString(RandomMethod::random(rng)),
+            13 => FieldValue::FieldArray(RandomMethod::random(rng)),
+            14 => FieldValue::Timestamp(RandomMethod::random(rng)),
+            15 => FieldValue::FieldTable(RandomMethod::random(rng)),
+            16 => FieldValue::Void,
+            _ => unreachable!(),
+        }
+    }
+}