From fbe30b8d0eb77db9ec91f81fb5c4042fc45e6402 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Fri, 25 Nov 2022 13:20:03 +0800
Subject: [PATCH] Change debugger init signature.

---
 CHANGELOG.md             | 8 +++++++-
 src/api/events.rs        | 4 +++-
 src/bin/rhai-dbg.rs      | 5 ++++-
 src/eval/debugger.rs     | 8 ++++----
 src/eval/global_state.rs | 3 ++-
 tests/debugging.rs       | 9 +++++----
 6 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58425903..869eba34 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,11 +4,16 @@ Rhai Release Notes
 Version 1.12.0
 ==============
 
-Buf fixes
+Bug fixes
 ---------
 
 * Integer numbers that are too large to deserialize into `INT` now fall back to `Decimal` or `FLOAT` instead of silently truncating.
 
+Breaking API changes
+--------------------
+
+* The callback for initializing a debugger instance has changed to `Fn(&Engine, Debugger) -> Debugger`. This allows more control over the initial setup of the debugger.
+
 Net features
 ------------
 
@@ -21,6 +26,7 @@ Net features
 Enhancements
 ------------
 
+* Optimizations have been done to key data structures to minimize size and creation time, which involves turning rarely-used fields into `Option<Box<T>>`. This resulted in some speed improvements.
 * `CallableFunction` is exported under `internals`.
 * The `TypeBuilder` type and `CustomType` trait are no longer marked as volatile.
 * `FuncArgs` is also implemented for arrays.
diff --git a/src/api/events.rs b/src/api/events.rs
index eff11efd..75499edf 100644
--- a/src/api/events.rs
+++ b/src/api/events.rs
@@ -349,7 +349,9 @@ impl Engine {
     #[inline(always)]
     pub fn register_debugger(
         &mut self,
-        init: impl Fn(&Self) -> Dynamic + SendSync + 'static,
+        init: impl Fn(&Self, crate::debugger::Debugger) -> crate::debugger::Debugger
+            + SendSync
+            + 'static,
         callback: impl Fn(
                 EvalContext,
                 crate::eval::DebuggerEvent,
diff --git a/src/bin/rhai-dbg.rs b/src/bin/rhai-dbg.rs
index b47f7a6d..bee052b7 100644
--- a/src/bin/rhai-dbg.rs
+++ b/src/bin/rhai-dbg.rs
@@ -604,7 +604,10 @@ fn main() {
     #[allow(deprecated)]
     engine.register_debugger(
         // Store the current source in the debugger state
-        |_| "".into(),
+        |engine, mut debugger| {
+            debugger.set_state(engine.const_empty_string());
+            debugger
+        },
         // Main debugging interface
         move |context, event, node, source, pos| {
             debug_callback(context, event, node, source, pos, &lines)
diff --git a/src/eval/debugger.rs b/src/eval/debugger.rs
index 93663293..14d0246a 100644
--- a/src/eval/debugger.rs
+++ b/src/eval/debugger.rs
@@ -10,10 +10,10 @@ use std::{fmt, iter::repeat, mem};
 
 /// Callback function to initialize the debugger.
 #[cfg(not(feature = "sync"))]
-pub type OnDebuggingInit = dyn Fn(&Engine) -> Dynamic;
+pub type OnDebuggingInit = dyn Fn(&Engine, Debugger) -> Debugger;
 /// Callback function to initialize the debugger.
 #[cfg(feature = "sync")]
-pub type OnDebuggingInit = dyn Fn(&Engine) -> Dynamic + Send + Sync;
+pub type OnDebuggingInit = dyn Fn(&Engine, Debugger) -> Debugger + Send + Sync;
 
 /// Callback function for debugging.
 #[cfg(not(feature = "sync"))]
@@ -268,12 +268,12 @@ impl Debugger {
     /// Create a new [`Debugger`].
     #[inline(always)]
     #[must_use]
-    pub const fn new(status: DebuggerStatus, state: Dynamic) -> Self {
+    pub const fn new(status: DebuggerStatus) -> Self {
         Self {
             status,
             break_points: Vec::new(),
             call_stack: Vec::new(),
-            state,
+            state: Dynamic::UNIT,
         }
     }
     /// Get the current call stack.
diff --git a/src/eval/global_state.rs b/src/eval/global_state.rs
index 408f71b0..1a9308e0 100644
--- a/src/eval/global_state.rs
+++ b/src/eval/global_state.rs
@@ -104,7 +104,8 @@ impl GlobalRuntimeState {
 
             #[cfg(feature = "debugging")]
             debugger: engine.debugger.as_ref().map(|x| {
-                crate::eval::Debugger::new(crate::eval::DebuggerStatus::Init, (x.0)(engine))
+                let dbg = crate::eval::Debugger::new(crate::eval::DebuggerStatus::Init);
+                (x.0)(engine, dbg)
             }),
         }
     }
diff --git a/tests/debugging.rs b/tests/debugging.rs
index 762ed9d2..46b419ca 100644
--- a/tests/debugging.rs
+++ b/tests/debugging.rs
@@ -12,7 +12,7 @@ fn test_debugging() -> Result<(), Box<EvalAltResult>> {
     let mut engine = Engine::new();
 
     engine.register_debugger(
-        |_| Dynamic::UNIT,
+        |_, dbg| dbg,
         |_, _, _, _, _| Ok(rhai::debugger::DebuggerCommand::Continue),
     );
 
@@ -47,19 +47,20 @@ fn test_debugger_state() -> Result<(), Box<EvalAltResult>> {
     let mut engine = Engine::new();
 
     engine.register_debugger(
-        |_| {
+        |_, mut debugger| {
             // Say, use an object map for the debugger state
             let mut state = Map::new();
             // Initialize properties
             state.insert("hello".into(), (42 as INT).into());
             state.insert("foo".into(), false.into());
-            Dynamic::from_map(state)
+            debugger.set_state(state);
+            debugger
         },
         |mut context, _, _, _, _| {
             // Print debugger state - which is an object map
             println!(
                 "Current state = {}",
-                context.global_runtime_state_mut().debugger().state()
+                context.global_runtime_state().debugger().state()
             );
 
             // Modify state