✅ extract unit test

src/main.rs

@@ -2,13 +2,30 @@ use std::collections::BTreeMap;
 
 enum Instruction {
 	VarArgPrep (i32),
+	
+	// Get Table, Upvalue
 	GetTabUp (u8, u8, u8),
+	
+	// Get Immediate?
 	GetI (u8, u8, u8),
+	
+	// Equals Constant?
 	EqK (u8, u8, u8),
+	
+	// Jump
 	Jmp (i32),
+	
+	// Load Integer?
+	LoadI (u8, i32),
+	
+	// Load Constant
 	LoadK (u8, i32),
+	
+	
 	Call (u8, u8, u8),
 	Closure (u8, i32),
+	
+	// (A, B, _C) Return B - 1 registers starting with  A
 	Return (u8, u8, u8),
 }
 
@@ -18,6 +35,7 @@ enum Value {
 	False,
 	True,
 	Float (f64),
+	Integer (i64),
 	String (String),
 	
 	// These are all bogus, I haven't figured out how to implement
@@ -46,6 +64,12 @@ impl From <&str> for Value {
 	}
 }
 
+impl From <i32> for Value {
+	fn from (x: i32) -> Self {
+		Self::Integer (x as i64)
+	}
+}
+
 struct Chunk {
 	instructions: Vec <Instruction>,
 	constants: Vec <Value>,
@@ -68,7 +92,8 @@ impl Default for VirtualMachine {
 }
 
 impl VirtualMachine {
-	fn execute_chunk (&mut self, chunk: &Chunk, upvalues: &Vec <Value>) {
+	fn execute_chunk (&mut self, chunk: &Chunk, upvalues: &Vec <Value>) 
+	-> Vec <Value> {
 		let max_iters = 2000;
 		
 		for _ in 0..max_iters {
@@ -135,21 +160,29 @@ impl VirtualMachine {
 					
 					let table = r.get (b).unwrap ();
 					let value = match table {
-						Value::BogusArg (arg) => arg.get (c).unwrap ().as_str().into (),
+						Value::BogusArg (arg) => arg.get (c).map (|x| x.as_str().into ()).unwrap_or_default(),
 						_ => unimplemented!(),
 					};
 					
 					r [a] = value;
 				},
-				Instruction::Jmp (sJ) => self.program_counter += sJ,
+				Instruction::Jmp (s_j) => self.program_counter += s_j,
+				Instruction::LoadI (a, sbx) => {
+					let a  = usize::try_from  (*a).unwrap ();
+					
+					r [a] = (*sbx).into ();
+				},
 				Instruction::LoadK (a, bx) => {
 					let a  = usize::try_from  (*a).unwrap ();
 					let bx = usize::try_from (*bx).unwrap ();
 					
 					r [a] = k [bx].clone ();
 				},
-				Instruction::Return (_a, _b, _c) => {
-					break;
+				Instruction::Return (a, b, _c) => {
+					let a = usize::try_from (*a).unwrap ();
+					let b = usize::try_from (*b).unwrap ();
+					
+					return self.registers [a..(a + b - 1)].to_vec();
 				},
 				Instruction::VarArgPrep (_) => (),
 				_ => (),
@@ -157,6 +190,8 @@ impl VirtualMachine {
 			
 			self.program_counter += 1;
 		}
+		
+		panic! ("Hit max iterations before chunk returned");
 	}
 }
 
@@ -166,17 +201,21 @@ fn main() {
 	let chunk = Chunk {
 		instructions: vec! [
 			Instruction::VarArgPrep (0),
-			Instruction::GetTabUp (0, 0, 0),
-			Instruction::GetI (0, 0, 1),
-			Instruction::EqK (0, 1, 0),
-			Instruction::Jmp (4),
-			Instruction::GetTabUp (0, 0, 2),
-			Instruction::LoadK (1, 3),
-			Instruction::Call (0, 2, 1),
-			Instruction::Jmp (3),
-			Instruction::GetTabUp (0, 0, 2),
-			Instruction::LoadK (1, 4),
-			Instruction::Call (0, 2, 1),
+			Instruction::GetTabUp (1, 0, 0),
+			Instruction::GetI (1, 1, 1),
+			Instruction::EqK (1, 1, 0),
+			Instruction::Jmp (6),
+			Instruction::GetTabUp (1, 0, 2),
+			Instruction::LoadK (2, 3),
+			Instruction::Call (1, 2, 1),
+			Instruction::LoadI (1, 0),
+			Instruction::Return (1, 2, 1),
+			Instruction::Jmp (5),
+			Instruction::GetTabUp (1, 0, 2),
+			Instruction::LoadK (2, 4),
+			Instruction::Call (1, 2, 1),
+			Instruction::LoadI (1, 1),
+			Instruction::Return (1, 2, 1),
 			Instruction::Return (1, 1, 1),
 		],
 		constants: vec! [
@@ -198,5 +237,74 @@ fn main() {
 	];
 	
 	let mut vm = VirtualMachine::default ();
-	vm.execute_chunk (&chunk, &upvalues);
+	println! ("Returned: {:?}", vm.execute_chunk (&chunk, &upvalues));
+}
+
+#[cfg (test)]
+mod tests {
+	use super::*;
+	
+	#[test]
+	fn is_93 () {
+		/*
+		if arg [1] == "93" then
+			print "it's 93"
+			return 0
+		else
+			print "it's not 93"
+			return 1
+		end
+		*/
+		
+		let chunk = Chunk {
+			instructions: vec! [
+				Instruction::VarArgPrep (0),
+				Instruction::GetTabUp (1, 0, 0),
+				Instruction::GetI (1, 1, 1),
+				Instruction::EqK (1, 1, 0),
+				Instruction::Jmp (6),
+				Instruction::GetTabUp (1, 0, 2),
+				Instruction::LoadK (2, 3),
+				Instruction::Call (1, 2, 1),
+				Instruction::LoadI (1, 0),
+				Instruction::Return (1, 2, 1),
+				Instruction::Jmp (5),
+				Instruction::GetTabUp (1, 0, 2),
+				Instruction::LoadK (2, 4),
+				Instruction::Call (1, 2, 1),
+				Instruction::LoadI (1, 1),
+				Instruction::Return (1, 2, 1),
+				Instruction::Return (1, 1, 1),
+			],
+			constants: vec! [
+				"arg",
+				"93",
+				"print",
+				"it's 93",
+				"it's not 93",
+			].into_iter ().map (|s| Value::from (s)).collect (),
+		};
+		
+		for (arg, expected) in [
+			(vec! ["_exe_name"], vec! [1.into ()]),
+			(vec! ["_exe_name", "93"], vec! [0.into ()]),
+			(vec! ["_exe_name", "94"], vec! [1.into ()]),
+		] {
+			let arg = arg.into_iter ().map (|s| s.to_string ()).collect ();
+			
+			let env = BTreeMap::from_iter ([
+				("arg", Value::BogusArg (arg)),
+				("print", Value::BogusPrint),
+			].map (|(k, v)| (k.to_string (), v)).into_iter ());
+			
+			let upvalues = vec! [
+				Value::BogusEnv (env),
+			];
+			
+			let mut vm = VirtualMachine::default ();
+			let actual = vm.execute_chunk (&chunk, &upvalues);
+			
+			assert_eq! (actual, expected);
+		}
+	}
 }

test_vectors/is_93.lua

@@ -1,9 +1,11 @@
-if arg [1] == "93" then
-	print "it's 93"
-else
-	print "it's not 93"
-end
-
 local function unused_fn ()
 	print "unused"
 end
+
+if arg [1] == "93" then
+	print "it's 93"
+	return 0
+else
+	print "it's not 93"
+	return 1
+end