From 66440a964932f3d0f57bba98213830b0bc1cd910 Mon Sep 17 00:00:00 2001
From: TopchetoEU <36534413+TopchetoEU@users.noreply.github.com>
Date: Fri, 13 Dec 2024 02:28:36 +0200
Subject: [PATCH] fix: a plethora of loop off by one and null issues

---
 .../jscript/compilation/control/DoWhileNode.java         | 2 --
 .../jscript/compilation/control/ForInNode.java           | 2 +-
 .../topchetoeu/jscript/compilation/control/ForNode.java  | 9 ++++-----
 .../jscript/compilation/control/WhileNode.java           | 4 ++--
 4 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/main/java/me/topchetoeu/jscript/compilation/control/DoWhileNode.java b/src/main/java/me/topchetoeu/jscript/compilation/control/DoWhileNode.java
index d50d19f..abf42ee 100644
--- a/src/main/java/me/topchetoeu/jscript/compilation/control/DoWhileNode.java
+++ b/src/main/java/me/topchetoeu/jscript/compilation/control/DoWhileNode.java
@@ -27,12 +27,10 @@ public class DoWhileNode extends Node {
 	@Override public void compile(CompileResult target, boolean pollute) {
 		int start = target.size();
 		var end = new DeferredIntSupplier();
-		var mid = new DeferredIntSupplier();
 
 		LabelContext.pushLoop(target.env, loc(), label, end, start);
 		body.compile(target, false, BreakpointType.STEP_OVER);
 
-		mid.set(target.size());
 		condition.compile(target, true, BreakpointType.STEP_OVER);
 		int endI = target.size();
 		end.set(endI + 1);
diff --git a/src/main/java/me/topchetoeu/jscript/compilation/control/ForInNode.java b/src/main/java/me/topchetoeu/jscript/compilation/control/ForInNode.java
index 77a210d..d620bd9 100644
--- a/src/main/java/me/topchetoeu/jscript/compilation/control/ForInNode.java
+++ b/src/main/java/me/topchetoeu/jscript/compilation/control/ForInNode.java
@@ -52,7 +52,7 @@ public class ForInNode extends Node {
 		target.add(Instruction.discard());
 		target.set(mid, Instruction.jmpIfNot(endI - mid + 1));
 
-		end.set(endI);
+		end.set(endI + 1);
 		LabelContext.popLoop(target.env, label);
 
 		if (pollute) target.add(Instruction.pushUndefined());
diff --git a/src/main/java/me/topchetoeu/jscript/compilation/control/ForNode.java b/src/main/java/me/topchetoeu/jscript/compilation/control/ForNode.java
index 32d0c59..25837ef 100644
--- a/src/main/java/me/topchetoeu/jscript/compilation/control/ForNode.java
+++ b/src/main/java/me/topchetoeu/jscript/compilation/control/ForNode.java
@@ -12,14 +12,13 @@ import me.topchetoeu.jscript.compilation.JavaScript;
 import me.topchetoeu.jscript.compilation.LabelContext;
 import me.topchetoeu.jscript.compilation.Node;
 import me.topchetoeu.jscript.compilation.VariableDeclareNode;
-import me.topchetoeu.jscript.compilation.values.operations.DiscardNode;
 
 public class ForNode extends Node {
 	public final Node declaration, assignment, condition, body;
 	public final String label;
 
 	@Override public void resolve(CompileResult target) {
-		declaration.resolve(target);
+		if (declaration != null) declaration.resolve(target);
 		body.resolve(target);
 	}
 	@Override public void compileFunctions(CompileResult target) {
@@ -46,11 +45,11 @@ public class ForNode extends Node {
 		if (assignment != null) assignment.compile(target, false, BreakpointType.STEP_OVER);
 		int endI = target.size();
 
-		end.set(endI);
+		end.set(endI + 1);
 		LabelContext.popLoop(target.env, label);
 
 		target.add(Instruction.jmp(start - endI));
-		if (mid >= 0) target.set(mid, Instruction.jmpIfNot(endI - mid + 1));
+		if (condition != null) target.set(mid, Instruction.jmpIfNot(endI - mid + 1));
 		if (pollute) target.add(Instruction.pushUndefined());
 	}
 
@@ -67,7 +66,7 @@ public class ForNode extends Node {
 		var n = Parsing.skipEmpty(src, i);
 
 		if (!src.is(i + n, ";")) return ParseRes.failed();
-		else return ParseRes.res(new DiscardNode(src.loc(i), null), n + 1);
+		else return ParseRes.res(null, n + 1);
 	}
 	private static ParseRes<Node> parseCondition(Source src, int i) {
 		var n = Parsing.skipEmpty(src, i);
diff --git a/src/main/java/me/topchetoeu/jscript/compilation/control/WhileNode.java b/src/main/java/me/topchetoeu/jscript/compilation/control/WhileNode.java
index a341cce..b687f2a 100644
--- a/src/main/java/me/topchetoeu/jscript/compilation/control/WhileNode.java
+++ b/src/main/java/me/topchetoeu/jscript/compilation/control/WhileNode.java
@@ -38,8 +38,8 @@ public class WhileNode extends Node {
 		end.set(endI + 1);
 		LabelContext.popLoop(target.env, label);
 
-		target.add(Instruction.jmp(start - end.getAsInt()));
-		target.set(mid, Instruction.jmpIfNot(end.getAsInt() - mid + 1));
+		target.add(Instruction.jmp(start - endI));
+		target.set(mid, Instruction.jmpIfNot(endI - mid + 1));
 		if (pollute) target.add(Instruction.pushUndefined());
 	}