Add debug feature to print latency

Cargo.toml

@@ -4,6 +4,8 @@ version = "0.1.0"
 authors = ["Artemis Tosini <me@artem.ist>"]
 edition = "2018"
 
+[features]
+check_latency = []
 
 [dependencies]
 async-trait = "0.1"

src/async_iter.rs

@@ -17,7 +17,6 @@ pub trait AsyncIter {
     }
 }
 
-
 #[cfg(test)]
 mod test {
     use super::*;

src/tile.rs

@@ -2,6 +2,8 @@ use serde::{ser::Serializer, Serialize};
 use smart_default::SmartDefault;
 use std::fmt::Debug;
 use std::sync::Arc;
+#[cfg(feature = "check_latency")]
+use std::time::Instant;
 //use tokio::sync::mpsc::{error::SendError, Sender};
 
 #[allow(unused)]
@@ -40,6 +42,16 @@ where
     serializer.serialize_str(arc)
 }
 
+#[cfg(feature = "check_latency")]
+fn time_diff<S>(&instant: &Instant, serializer: S) -> Result<S::Ok, S::Error>
+where
+    S: Serializer,
+{
+    let duration = Instant::now() - instant;
+    //let duration = duration.as_secs_f32();
+    serializer.serialize_str(&format!("{:?}", duration))
+}
+
 #[derive(Clone, Serialize, Debug, SmartDefault)]
 pub struct Block {
     pub full_text: Box<str>,
@@ -75,6 +87,10 @@ pub struct Block {
     pub separator_block_width: Option<u32>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub markup: Option<Markup>,
+    #[serde(serialize_with = "time_diff")]
+    #[default(Instant::now())]
+    #[cfg(feature = "check_latency")]
+    pub latency: Instant,
 }
 
 #[derive(Clone, Debug)]