supports testing for vm

Cargo.toml

@@ -15,5 +15,6 @@ lox-ir = { path="components/lox-ir" }
 lox-parse = { path="components/lox-parse" }
 lox-lex = { path="components/lox-lex" }
 lox-compile = { path="components/lox-compile" }
+lox-execute = { path="components/lox-execute" }
 tracing = "0.1.37"
 tracing-subscriber = { version = "0.3.17", features = ["env-filter"] }

components/lox-execute/Cargo.toml

@@ -9,3 +9,4 @@ edition = "2021"
 salsa = { path="../salsa" }
 lox-ir = { path="../lox-ir" }
 lox-compile = { path="../lox-compile" }
+tracing = "0.1.37"

components/lox-execute/src/execute.rs

@@ -0,0 +1,12 @@
+use lox_compile::compile;
+use lox_ir::input_file::InputFile;
+
+use crate::vm::VM;
+
+
+// FIXME: This should not return a `f64`, but for now it's convenient as our compiler is more or less a calculator for now.
+pub fn execute_file(db: &impl crate::Db, input_file: InputFile) -> f64 {
+    let chunk = compile::compile_file(db, input_file);
+    let mut vm = VM::new(chunk);
+    vm.interpret()
+}

components/lox-execute/src/lib.rs

@@ -1,6 +1,9 @@
 #![feature(trait_upcasting)]
 
 pub mod vm;
+pub mod execute;
+
+pub use execute::execute_file;
 
 
 #[salsa::jar(db = Db)]

components/lox-execute/src/vm.rs

@@ -10,11 +10,20 @@ pub struct VM {
 }
 
 impl VM {
-    pub fn interpret(&mut self) {
+    pub fn new(chunk: bytecode::Chunk) -> Self { Self { chunk, ip: 0, stack: Vec::new() } }
+
+    // FIXME: `interpret` should not return a `f64`, but for now it's convenient as
+    //  our compiler is more or less a calculator.
+    pub fn interpret(&mut self) -> f64 {
         loop {
+            if self.chunk.len() <= self.ip {
+                break;
+            }
+            tracing::debug!("ip: {}", self.ip);
+            tracing::debug!("stack: {:?}", self.stack);
             let instruction = self.read_byte();
             match instruction {
-                bytecode::Code::Return => return,
+                bytecode::Code::Return => break,
                 bytecode::Code::Constant(value) => {
                     self.push(value.into())
                 },
@@ -40,6 +49,7 @@ impl VM {
                 },
             }
         }
+        self.stack.pop().unwrap()
     }
 
     fn read_byte(&mut self) -> bytecode::Code {

components/lox-ir/src/bytecode.rs

@@ -22,4 +22,8 @@ impl Chunk {
     pub fn read_byte(&self, ip: usize) -> Code {
         self.code[ip].clone()
     }
+
+    pub fn len(&self) -> usize {
+        self.code.len()
+    }
 }

lox_tests/arithmetic.lox

@@ -1 +1 @@
-print 1 + 2
+1 + 2

lox_tests/arithmetic.output

@@ -0,0 +1 @@
+3.0

src/main.rs

@@ -5,6 +5,7 @@ struct TestCase {
     lox: PathBuf,
     syntax: PathBuf,
     bytecode: PathBuf,
+    output: PathBuf,
     text: String,
 }
 
@@ -27,8 +28,9 @@ impl TestCase {
                 let lox = path;
                 let syntax = lox.with_extension("syntax");
                 let bytecode = lox.with_extension("bytecode");
+                let output = lox.with_extension("output");
                 let text = fs::read_to_string(&lox).unwrap();
-                res.push(TestCase { lox, syntax, bytecode, text });
+                res.push(TestCase { lox, syntax, bytecode, output, text });
             }
         }
         res.sort();
@@ -39,7 +41,7 @@ impl TestCase {
 use expect_test::expect_file;
 use lox_ir::{word::Word, input_file::InputFile, diagnostic::Diagnostics};
 
-#[salsa::db(lox_parse::Jar, lox_ir::Jar, lox_lex::Jar, lox_compile::Jar)]
+#[salsa::db(lox_parse::Jar, lox_ir::Jar, lox_lex::Jar, lox_compile::Jar, lox_execute::Jar)]
 #[derive(Default)]
 struct Database {
     storage: salsa::Storage<Self>,
@@ -93,5 +95,10 @@ fn main() {
         // test bytecode
         let chunk = lox_compile::compile_file(&db, input_file);
         expect_file![case.bytecode].assert_eq(&format!("{:#?}", chunk));
+
+        // test execute
+        let output = lox_execute::execute_file(&db, input_file);
+        expect_file![case.output].assert_eq(&format!("{:#?}", output));
+
     }
 }