Fix new rr crate to be no_std

Author: arjunr2

Cargo.lock

@@ -18,6 +18,7 @@ all-features = true
 [dependencies]
 wasmtime-environ = { workspace = true, features = ["component-model"] }
 serde = { workspace = true }
+serde_derive = { workspace = true }
 postcard = { workspace = true }
 anyhow = { workspace = true }
 log = { workspace = true }

crates/rr/Cargo.toml

@@ -1,4 +1,4 @@
-use crate::ReplayError;
+use crate::{ReplayError, prelude::*};
 use anyhow::Result;
 use core::fmt;
 use serde::{Deserialize, Serialize};

crates/rr/src/events.rs

@@ -1,10 +1,10 @@
-use super::RREvent;
-use anyhow::Result;
+use crate::{RREvent, prelude::*};
 use core::any::Any;
 use postcard;
 
 cfg_if::cfg_if! {
     if #[cfg(feature = "std")] {
+        extern crate std;
         use std::io::{Write, Seek, Read};
         /// A writer for recording in RR.
         pub trait RecordWriter: Write + Send + Sync + Any {}

crates/rr/src/io.rs

@@ -1,13 +1,24 @@
-use anyhow::Result;
-use core::fmt;
+#![no_std]
+
+pub(crate) mod prelude {
+    pub use anyhow::{self, Result};
+    pub use serde::{Deserialize, Serialize};
+    pub use wasmtime_environ::prelude::*;
+}
+
+use crate::prelude::*;
+pub use core::fmt;
 pub use events::{
     EventError, RRFuncArgVals, ResultEvent, Validate, common_events, component_events, core_events,
 };
+use events::{component_events::RRComponentInstanceId, core_events::RRModuleInstanceId};
 pub use io::{RecordWriter, ReplayReader, from_replay_reader, to_record_writer};
-use serde::{Deserialize, Serialize};
 use wasmtime_environ::{EntityIndex, WasmChecksum};
 
-use events::{component_events::RRComponentInstanceId, core_events::RRModuleInstanceId};
+/// Encapsulation of event types comprising an [`RREvent`] sum type
+mod events;
+/// I/O support for reading and writing traces
+mod io;
 
 /// Settings for execution recording.
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -45,11 +56,6 @@ impl Default for ReplaySettings {
     }
 }
 
-/// Encapsulation of event types comprising an [`RREvent`] sum type
-mod events;
-/// I/O support for reading and writing traces
-mod io;
-
 /// Macro template for [`RREvent`] and its conversion to/from specific
 /// event types
 macro_rules! rr_event {