DEV: Working Trace statements

src/build/opcode/mod.rs

@@ -28,6 +28,8 @@ pub use vm::VM;
 use pointer::OpPointer;
 use scope::Stack;
 
+use crate::ast::Position;
+
 #[derive(Debug, PartialEq, Clone)]
 pub enum Primitive {
     // Primitive Types
@@ -146,6 +148,7 @@ pub enum Hook {
     Convert,
     Regex,
     Range,
+    Trace(Position),
 }
 
 #[derive(Debug, PartialEq, Clone)]

src/build/opcode/runtime.rs

@@ -12,9 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 use std::collections::BTreeMap;
+use std::convert::TryFrom;
 use std::convert::TryInto;
 use std::fs::File;
-use std::io::Read;
+use std::io::{Read, Write};
 use std::path::{Path, PathBuf};
 use std::rc::Rc;
 
@@ -24,12 +25,14 @@ use super::cache;
 use super::Value::{C, F, P};
 use super::VM;
 use super::{Composite, Error, Hook, Primitive, Value};
+use crate::ast::Position;
+use crate::build::ir::Val;
 use crate::build::AssertCollector;
 use crate::convert::{ConverterRegistry, ImporterRegistry};
 use Composite::{List, Tuple};
-use Primitive::{Bool, Empty, Str, Int};
+use Primitive::{Bool, Empty, Int, Str};
 
-pub struct Builtins {
+pub struct Builtins<Out: Write, Err: Write> {
     op_cache: cache::Ops,
     val_cache: BTreeMap<String, Rc<Value>>,
     assert_results: AssertCollector,
@@ -37,28 +40,40 @@ pub struct Builtins {
     importer_registry: ImporterRegistry,
     working_dir: PathBuf,
     import_path: Vec<PathBuf>,
-    // TODO(jwall): IO sink for stderr
+    stdout: Out,
-    // TODO(jwall): IO sink for stdout
+    stderr: Err,
 }
 
-impl Builtins {
+type ByteSink = Vec<u8>;
-    pub fn new() -> Self {
+
-        Self::with_working_dir(std::env::current_dir().unwrap())
+impl<Out: Write, Err: Write> Builtins<Out, Err> {
+    pub fn new(out: Out, err: Err) -> Self {
+        Self::with_working_dir(std::env::current_dir().unwrap(), out, err)
     }
 
-    pub fn with_working_dir<P: Into<PathBuf>>(path: P) -> Self {
+    pub fn with_working_dir<P: Into<PathBuf>>(path: P, out: Out, err: Err) -> Self {
         Self {
             op_cache: cache::Ops::new(),
             val_cache: BTreeMap::new(),
             assert_results: AssertCollector::new(),
             converter_registry: ConverterRegistry::make_registry(),
             importer_registry: ImporterRegistry::make_registry(),
-            // TODO(jwall): This should move into the VM and not in the Runtime.
+            // FIXME(jwall): This should move into the VM and not in the Runtime.
             working_dir: path.into(),
             import_path: Vec::new(),
+            stdout: out,
+            stderr: err,
         }
     }
 
+    pub fn get_stdout(&self) -> &Out {
+        &self.stdout
+    }
+
+    pub fn get_stderr(&self) -> &Err {
+        &self.stderr
+    }
+
     pub fn handle<P: AsRef<Path>>(
         &mut self,
         path: P,
@@ -76,6 +91,7 @@ impl Builtins {
             Hook::Reduce => self.reduce(path, stack),
             Hook::Regex => self.regex(stack),
             Hook::Range => self.range(stack),
+            Hook::Trace(pos) => self.trace(stack, pos),
         }
     }
 
@@ -488,4 +504,30 @@ impl Builtins {
         stack.push(Rc::new(C(List(elems))));
         Ok(())
     }
+
+    fn trace(&mut self, mut stack: &mut Vec<Rc<Value>>, pos: Position) -> Result<(), Error> {
+        let val = if let Some(val) = dbg!(stack.pop()) {
+            val
+        } else {
+            return Err(dbg!(Error {}));
+        };
+        let expr = stack.pop();
+        let expr_pretty = match expr {
+            Some(ref expr) => match dbg!(expr.as_ref()) {
+                &P(Str(ref expr)) => expr.clone(),
+                _ => return Err(dbg!(Error {})),
+            },
+            _ => return Err(dbg!(Error {})),
+        };
+        let writable_val: Val = TryFrom::try_from(val.clone())?;
+        if let Err(_) = writeln!(
+            &mut self.stderr,
+            "TRACE: {} = {} at {}",
+            expr_pretty, writable_val, pos
+        ) {
+            return Err(dbg!(Error {}));
+        };
+        stack.push(val);
+        Ok(())
+    }
 }

src/build/opcode/test.rs

@@ -754,3 +754,19 @@ fn simple_selects() {
         "select \"quux\", 3, { foo = 1, bar = 2, };" => P(Int(3)),
     ];
 }
+
+#[test]
+fn simple_trace() {
+    let stmts = parse(OffsetStrIter::from(dbg!("TRACE 1+1;")), None).unwrap();
+    let ops = Rc::new(translate::AST::translate(stmts));
+    assert!(ops.len() > 0);
+    let mut vm = VM::new("foo.ucg", ops.clone());
+    vm.run().unwrap();
+    assert_eq!(vm.pop().unwrap(), Rc::new(P(Int(2))));
+    let runtime = vm.get_runtime();
+    let err_out = runtime.get_stderr();
+    assert_eq!(
+        String::from_utf8_lossy(err_out).to_owned(),
+        "TRACE: 1 + 1 = 2 at line: 1 column: 1\n"
+    );
+}

src/build/opcode/translate.rs

@@ -402,7 +402,15 @@ impl AST {
                 ops.push(Op::Cp);
             }
             Expression::Debug(def) => {
-                unimplemented!("Debug expressions are not implmented yet");
+                let mut buffer: Vec<u8> = Vec::new();
+                {
+                    let mut printer = crate::ast::printer::AstPrinter::new(2, &mut buffer);
+                    let _ = printer.render_expr(&def.expr);
+                }
+                let expr_pretty = String::from_utf8(buffer).unwrap();
+                ops.push(Op::Val(Primitive::Str(expr_pretty)));
+                Self::translate_expr(*def.expr, &mut ops);
+                ops.push(Op::Runtime(Hook::Trace(def.pos)));
             }
         }
     }

src/build/opcode/vm.rs

@@ -11,6 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
+use std::cell::Ref;
 use std::cell::RefCell;
 use std::path::PathBuf;
 use std::rc::Rc;
@@ -28,7 +29,8 @@ use super::{Func, Module};
 pub struct VM {
     stack: Vec<Rc<Value>>,
     symbols: Stack,
-    runtime: Rc<RefCell<runtime::Builtins>>,
+    // FIXME(jwall): This should be parameterized.
+    runtime: Rc<RefCell<runtime::Builtins<Vec<u8>, Vec<u8>>>>,
     ops: OpPointer,
     // TODO(jwall): This should be optional
     path: PathBuf,
@@ -43,12 +45,16 @@ impl<'a> VM {
         Self {
             stack: Vec::new(),
             symbols: Stack::new(),
-            runtime: Rc::new(RefCell::new(runtime::Builtins::new())),
+            runtime: Rc::new(RefCell::new(runtime::Builtins::new(Vec::new(), Vec::new()))),
             ops: ops,
             path: path.into(),
         }
     }
 
+    pub fn get_runtime(&self) -> Ref<runtime::Builtins<Vec<u8>, Vec<u8>>> {
+        self.runtime.as_ref().borrow()
+    }
+
     pub fn to_scoped(self, symbols: Stack) -> Self {
         Self {
             stack: Vec::new(),