From 954f6312b8545c2ab175263fee3f3c6e76f30178 Mon Sep 17 00:00:00 2001
From: Brian Fiete <bfiete@gmail.com>
Date: Mon, 2 Aug 2021 10:42:53 -0700
Subject: [PATCH] Changed mixin circular reference detection

---
 IDE/Tests/CompileFail001/src/Methods.bf | 29 +++++++++++
 IDEHelper/Compiler/BfExprEvaluator.cpp  | 64 +++++++++++++------------
 IDEHelper/Tests/src/Mixins.bf           | 30 ++++++++++++
 3 files changed, 92 insertions(+), 31 deletions(-)

diff --git a/IDE/Tests/CompileFail001/src/Methods.bf b/IDE/Tests/CompileFail001/src/Methods.bf
index 2794fa2b..51c2505d 100644
--- a/IDE/Tests/CompileFail001/src/Methods.bf
+++ b/IDE/Tests/CompileFail001/src/Methods.bf
@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 
 namespace IDETest
 {
@@ -55,11 +56,39 @@ namespace IDETest
 
 		}
 
+		public static mixin MixinA()
+		{
+			MixinA!(); //FAIL
+		}
+
+		public static mixin MixinB<T>(T val) where T : var
+		{
+		}
+
+		public static mixin MixinB<T, T2>(T val) where T : List<T2>
+		{
+			MixinB!(val);
+		}
+
+		public static mixin MixinC<T>(T val) where T : var
+		{
+		}
+
+		public static mixin MixinC<T, T2>(T val) where T : List<T2>
+		{
+			if (!val.IsEmpty)
+				MixinC!(val.Front);
+		}
+
 		public static void Test()
 		{
 			ClassB cb = scope .();
 			MethodA(cb, 123); //FAIL
 			MethodB(cb, 234); //FAIL
+
+			List<List<int>> list = scope .();
+			MixinB!(list); //FAIL
+			MixinC!(list);
 		}
 	}
 }
diff --git a/IDEHelper/Compiler/BfExprEvaluator.cpp b/IDEHelper/Compiler/BfExprEvaluator.cpp
index 90cab4c0..67c8368f 100644
--- a/IDEHelper/Compiler/BfExprEvaluator.cpp
+++ b/IDEHelper/Compiler/BfExprEvaluator.cpp
@@ -15200,38 +15200,40 @@ void BfExprEvaluator::InjectMixin(BfAstNode* targetSrc, BfTypedValue target, boo
 	
 	auto curMethodState = mModule->mCurMethodState;
 	//
-	{
-		bool hasCircularRef = false;
 
-		auto checkMethodState = curMethodState;
-		while (checkMethodState != NULL)
-		{			
-			auto curMixinState = checkMethodState->mMixinState;
-			while (curMixinState != NULL)
-			{
-				if (curMixinState->mSource == targetSrc)				
-					hasCircularRef = true;									
-				curMixinState = curMixinState->mPrevMixinState;
-			}
-
-			if ((checkMethodState->mClosureState != NULL) && (checkMethodState->mClosureState->mActiveDeferredLocalMethod != NULL))
-			{
-				for (auto& mixinRecord : checkMethodState->mClosureState->mActiveDeferredLocalMethod->mMixinStateRecords)
-				{
-					if (mixinRecord.mSource == targetSrc)					
-						hasCircularRef = true;					
-				}
-			}
-
-			checkMethodState = checkMethodState->mPrevMethodState;
-		}
-
-		if (hasCircularRef)
-		{
-			mModule->Fail("Circular reference detected between mixins", targetSrc);
-			return;
-		}
-	}
+	// Why was this required? It doesn't check for matching generic args (we only want to throw an error if we call back into a mixin with the same generic args as before)
+// 	{
+// 		bool hasCircularRef = false;
+// 
+// 		auto checkMethodState = curMethodState;
+// 		while (checkMethodState != NULL)
+// 		{			
+// 			auto curMixinState = checkMethodState->mMixinState;
+// 			while (curMixinState != NULL)
+// 			{
+// 				if (curMixinState->mSource == targetSrc)				
+// 					hasCircularRef = true;									
+// 				curMixinState = curMixinState->mPrevMixinState;
+// 			}
+// 
+// 			if ((checkMethodState->mClosureState != NULL) && (checkMethodState->mClosureState->mActiveDeferredLocalMethod != NULL))
+// 			{
+// 				for (auto& mixinRecord : checkMethodState->mClosureState->mActiveDeferredLocalMethod->mMixinStateRecords)
+// 				{
+// 					if (mixinRecord.mSource == targetSrc)					
+// 						hasCircularRef = true;					
+// 				}
+// 			}
+// 
+// 			checkMethodState = checkMethodState->mPrevMethodState;
+// 		}
+// 
+// 		if (hasCircularRef)
+// 		{
+// 			mModule->Fail("Circular reference detected between mixins", targetSrc);
+// 			return;
+// 		}
+// 	}
 	
 	auto moduleMethodInstance = GetSelectedMethod(targetSrc, methodMatcher.mBestMethodTypeInstance, methodMatcher.mBestMethodDef, methodMatcher);
 	if (!moduleMethodInstance)
diff --git a/IDEHelper/Tests/src/Mixins.bf b/IDEHelper/Tests/src/Mixins.bf
index 288d74e9..b7078cf3 100644
--- a/IDEHelper/Tests/src/Mixins.bf
+++ b/IDEHelper/Tests/src/Mixins.bf
@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 
 namespace Tests
 {
@@ -47,6 +48,31 @@ namespace Tests
 			a = 234;
 		}
 
+		public static mixin CircularMixin<T>(T value)
+			where T : var
+		{
+			10
+		}
+
+		public static mixin CircularMixin<K, V>(Dictionary<K, V> value)
+			where K : var, IHashable
+			where V : var
+		{
+			
+			int total = 0;
+			if (value == null)
+				total += 1;
+			else
+			{
+				for (let (k, v) in ref value)
+				{
+					total += CircularMixin!(k);
+					total += CircularMixin!(*v);
+				}
+			}
+			total + 100
+		}
+
 		[Test]
 		public static void TestBasics()
 		{
@@ -73,6 +99,10 @@ namespace Tests
 					CheckStr(sv.ToScopeCStr!());
 				};
 			func("Test");
+
+			Dictionary<int, Dictionary<int, int>> test = scope .() {(1,null)};
+			int val = CircularMixin!(test);
+			Test.Assert(val == 211);
 		}
 
 		[Test]