Merge pull request #73 from FredTheDino/error-rewrite

error rewrite

2 files changed, 93 insertions, 58 deletions

diff --git a/src/error.rs b/src/error.rs
index deab89e..c2ad228 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -12,9 +12,16 @@ use crate::tokenizer::Token;
 #[derive(Debug, Clone)]
 pub enum ErrorKind {
     TypeError(Op, Vec<Type>),
+    TypeMismatch(Type, Type),
+    CannotInfer(Type, Type),
+    ArgumentType(Vec<Type>, Vec<Type>),
+    IndexError(Value, Type),
+
     /// (External function, parameters)
     ExternTypeMismatch(String, Vec<Type>),
-    RuntimeTypeError(Op, Vec<Value>),
+    ValueError(Op, Vec<Value>),
+    UnknownField(Value, String),
+    ArgumentCount(usize, usize),
 
     /// (Indexed value, length, index)
     IndexOutOfBounds(Value, usize, usize),
@@ -42,40 +49,69 @@ impl fmt::Display for ErrorKind {
                 let types = types
                     .iter()
                     .fold(String::new(), |a, v| { format!("{}{:?}, ", a, v) });
-                write!(f, "{} Cannot apply {:?} to types {}", "Type Error".bold(), op, types)
+                write!(f, "Cannot apply {:?} to types {}", op, types)
+            }
+            ErrorKind::TypeMismatch(a, b) => {
+                write!(f, "Expected '{:?}' and got '{:?}'.", a, b)
+            }
+            ErrorKind::CannotInfer(a, b) => {
+                write!(f, "Failed to infer type '{:?}' from '{:?}'.", a, b)
+            }
+            ErrorKind::ArgumentType(a, b) => {
+                let expected = a
+                    .iter()
+                    .fold(String::new(), |a, v| { format!("{}{:?}, ", a, v) });
+                let given = b
+                    .iter()
+                    .fold(String::new(), |a, v| { format!("{}{:?}, ", a, v) });
+                write!(f, "Argument types do not match, expected [{:?}] but got [{:?}]",
+                       expected, given)
             }
             ErrorKind::IndexOutOfBounds(value, len, slot) => {
-                write!(f, "{} for {:?} - length is {} but index is {}", "Index Error".bold(), value, len, slot)
+                write!(f, "Failed to index for {:?} - length is {} but index is {}",
+                       value, len, slot)
             }
             ErrorKind::ExternTypeMismatch(name, types) => {
-                write!(f, "{} Extern function '{}' doesn't accept argument(s) with type(s) {:?}", "Type Error".bold(), name, types)
+                write!(f, "Extern function '{}' doesn't accept argument(s) with type(s) {:?}",
+                       name, types)
             }
-            ErrorKind::RuntimeTypeError(op, values) => {
+            ErrorKind::ValueError(op, values) => {
                 let values = values
                     .iter()
                     .fold(String::new(), |a, v| { format!("{}{:?}, ", a, v) });
-                write!(f, "{} Cannot apply {:?} to values {}", "Runtime Type Error".bold(), op, values)
+                write!(f, "Cannot apply {:?} to values {}", op, values)
             }
             ErrorKind::AssertFailed => {
-                write!(f, "{}", "Assertion failed".bold())
+                write!(f, "Assertion failed")
             }
             ErrorKind::SyntaxError(line, token) => {
-                write!(f, "{} on line {} at token {:?}", "Syntax Error".bold(), line, token)
+                write!(f, "Syntax Error on line {} at token {:?}", line, token)
             }
             ErrorKind::Unreachable => {
-                write!(f, "{}", "Unreachable".bold())
+                write!(f, "Reached unreachable code.")
             }
             ErrorKind::InvalidProgram => {
                 write!(f, "{}", "[!!] Invalid program [!!]".bold())
             }
+            ErrorKind::IndexError(value, slot) => {
+                write!(f, "Cannot index value '{:?}' with type '{:?}'.", value, slot)
+            }
+            ErrorKind::UnknownField(obj, field) => {
+                write!(f, "Cannot find field '{}' on {:?}", field, obj)
+            }
+            ErrorKind::ArgumentCount(expected, given) => {
+                write!(f, "Incorrect argument count, expected {} but got {}.",
+                       expected, given)
+            }
         }
     }
 }
 
 impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let prompt = "*****".red();
         let message = match &self.message {
-            Some(s) => format!("\n{} {}", ">>>".red(), s),
+            Some(s) => format!("\n{} {}", prompt, s),
             None => String::from(""),
         };
 
@@ -87,7 +123,8 @@ impl fmt::Display for Error {
             String::new()
         };
 
-        write!(f, "\n<{}> {}:{} {}{}{}\n", "ERR".red(), self.file.display().blue(), self.line.blue(), self.kind, message, line)
+        write!(f, "\n {}  {}:{} \n{} {}{}{}\n", "ERR".red(),
+               self.file.display().blue(), self.line.blue(), prompt, self.kind, message, line)
     }
 }
 
diff --git a/src/vm.rs b/src/vm.rs
index bfb5ce4..020e90c 100644
--- a/src/vm.rs
+++ b/src/vm.rs
@@ -16,7 +16,7 @@ macro_rules! error {
         return Err($thing.error($kind, None));
     };
     ( $thing:expr, $kind:expr, $msg:expr) => {
-        return Err($thing.error($kind, Some($msg)));
+        return Err($thing.error($kind, Some(String::from($msg))));
     };
 }
 
@@ -26,7 +26,7 @@ macro_rules! one_op {
         let b = $fun(&a);
         if b.is_nil() {
             $self.push(b);
-            error!($self, ErrorKind::RuntimeTypeError($op, vec![a]));
+            error!($self, ErrorKind::TypeError($op, vec![a.into()]));
         }
         $self.push(b);
     };
@@ -38,7 +38,7 @@ macro_rules! two_op {
         let c = $fun(&a, &b);
         if c.is_nil() {
             $self.push(c);
-            error!($self, ErrorKind::RuntimeTypeError($op, vec![a, b]));
+            error!($self, ErrorKind::TypeError($op, vec![a.into(), b.into()]));
         }
         $self.push(c);
     };
@@ -280,7 +280,7 @@ impl VM {
                         Value::Function(ups, block)
                     },
                     value => error!(self,
-                        ErrorKind::RuntimeTypeError(op, vec![value.clone()]),
+                        ErrorKind::ValueError(op, vec![value.clone()]),
                         format!("Not a function {:?}.", value)),
                 };
                 self.constants[slot] = constant;
@@ -301,7 +301,7 @@ impl VM {
                     }
                     (val, slot) => {
                         self.stack.push(Value::Nil);
-                        error!(self, ErrorKind::RuntimeTypeError(op, vec![val, slot]), String::from("Cannot index type"));
+                        error!(self, ErrorKind::IndexError(val, slot.into()));
                     }
                 }
             }
@@ -313,7 +313,7 @@ impl VM {
                     let slot = ty.fields.get(field).unwrap().0;
                     self.push(values.borrow()[slot].clone());
                 } else {
-                    error!(self, ErrorKind::RuntimeTypeError(op, vec![inst]));
+                    error!(self, ErrorKind::UnknownField(inst, field.clone()));
                 }
             }
 
@@ -324,7 +324,7 @@ impl VM {
                     let slot = ty.fields.get(field).unwrap().0;
                     values.borrow_mut()[slot] = value;
                 } else {
-                    error!(self, ErrorKind::RuntimeTypeError(op, vec![inst]));
+                    error!(self, ErrorKind::UnknownField(inst, field.clone()));
                 }
             }
 
@@ -432,10 +432,7 @@ impl VM {
                         let inner = block.borrow();
                         let args = inner.args();
                         if args.len() != num_args {
-                            error!(self,
-                                ErrorKind::InvalidProgram,
-                                format!("Invalid number of arguments, got {} expected {}.",
-                                    num_args, args.len()));
+                            error!(self, ErrorKind::ArgumentCount(args.len(), num_args));
                         }
 
                         if self.print_blocks {
@@ -452,7 +449,7 @@ impl VM {
                         let extern_func = self.extern_functions[slot];
                         let res = match extern_func(&self.stack[new_base+1..], false) {
                             Ok(value) => value,
-                            Err(ek) => error!(self, ek, "Wrong arguments to external function".to_string()),
+                            Err(ek) => error!(self, ek, "Failed in external function."),
                         };
                         self.stack.truncate(new_base);
                         self.push(res);
@@ -575,10 +572,7 @@ impl VM {
                                 *ty = suggestion.clone();
                             } else {
                                 if ty != suggestion {
-                                    error!(self,
-                                           ErrorKind::TypeError(op,
-                                                    vec![ty.clone(), suggestion.clone()]),
-                                           "Failed to infer type.".to_string());
+                                    error!(self, ErrorKind::CannotInfer(ty.clone(), suggestion.clone()));
                                 }
                             }
                         };
@@ -596,8 +590,9 @@ impl VM {
                     let value = Value::from(ty.fields.get(field).unwrap().1.clone());
                     self.push(value);
                 } else {
+                    let field = field.clone();
                     self.push(Value::Nil);
-                    error!(self, ErrorKind::RuntimeTypeError(op, vec![inst]));
+                    error!(self, ErrorKind::UnknownField(inst, field));
                 }
             }
 
@@ -607,11 +602,13 @@ impl VM {
 
                 if let Value::Instance(ty, _) = inst {
                     let ty = &ty.fields.get(field).unwrap().1;
-                    if ty != &Type::from(&value) {
-                        error!(self, ErrorKind::RuntimeTypeError(op, vec![Value::from(ty)]));
+                    let expected = Type::from(&value);
+                    if ty != &expected {
+                        error!(self, ErrorKind::TypeMismatch(expected, ty.clone()),
+                               "Types of field and variable do not match.");
                     }
                 } else {
-                    error!(self, ErrorKind::RuntimeTypeError(op, vec![inst]));
+                    error!(self, ErrorKind::UnknownField(inst, field.clone()));
                 }
             }
 
@@ -628,8 +625,18 @@ impl VM {
                 let var = self.frame().block.borrow().upvalues[slot].2.clone();
                 let up = self.pop().into();
                 if var != up {
-                    error!(self, ErrorKind::TypeError(op, vec![var, up]),
-                                  "Incorrect type for upvalue.".to_string());
+                    error!(self, ErrorKind::TypeMismatch(up, var),
+                           "Captured varibles type doesn't match upvalue.");
+                }
+            }
+
+            Op::AssignLocal(slot) => {
+                let slot = self.frame().stack_offset + slot;
+                let curr = Type::from(&self.stack[slot]);
+                let other = Type::from(self.pop());
+                if curr != other {
+                    error!(self, ErrorKind::TypeMismatch(curr, other),
+                           "Cannot assign to different type.");
                 }
             }
 
@@ -638,9 +645,8 @@ impl VM {
                 let inner = self.frame().block.borrow();
                 let ret = inner.ret();
                 if Type::from(&a) != *ret {
-                    error!(self, ErrorKind::TypeError(op, vec![a.into(),
-                                                               ret.clone()]),
-                                                      "Not matching return type.".to_string());
+                    error!(self, ErrorKind::TypeMismatch(a.into(), ret.clone()),
+                           "Value does not match return type.");
                 }
             }
 
@@ -655,12 +661,8 @@ impl VM {
                     (Type::Unknown, top_type)
                         if top_type != Type::Unknown => {}
                     (a, b) if a != &b => {
-                        error!(self,
-                            ErrorKind::TypeError(
-                                op,
-                                vec![a.clone(), b.clone()]),
-                                format!("Tried to assign a type {:?} to type {:?}.", a, b)
-                        );
+                        error!(self, ErrorKind::TypeMismatch(a.clone(), b.clone()),
+                               "Cannot assign mismatching types.");
                     }
                     _ => {}
                 }
@@ -699,19 +701,13 @@ impl VM {
                         let inner = block.borrow();
                         let args = inner.args();
                         if args.len() != num_args {
-                            error!(self,
-                                ErrorKind::InvalidProgram,
-                                format!("Invalid number of arguments, got {} expected {}.",
-                                    num_args, args.len()));
+                            error!(self, ErrorKind::ArgumentCount(args.len(), num_args));
                         }
 
                         let stack_args = &self.stack[self.stack.len() - args.len()..];
                         let stack_args: Vec<_> = stack_args.iter().map(|x| x.into()).collect();
                         if args != &stack_args {
-                            error!(self,
-                                ErrorKind::TypeError(op, vec![]),
-                                format!("Expected args of type {:?} but got {:?}.",
-                                    args, stack_args));
+                            error!(self, ErrorKind::ArgumentType(args.clone(), stack_args));
                         }
 
                         self.stack[new_base] = block.borrow().ret().into();
@@ -725,16 +721,15 @@ impl VM {
                             Err(ek) => {
                                 self.stack.truncate(new_base);
                                 self.push(Value::Nil);
-                                error!(self, ek, "Wrong arguments to external function".to_string())
+                                error!(self, ek, "Error from external function.")
                             }
                         };
                         self.stack.truncate(new_base);
                         self.push(res);
                     }
                     _ => {
-                        error!(self,
-                            ErrorKind::TypeError(op, vec![Type::from(&self.stack[new_base])]),
-                            format!("Tried to call non-function {:?}", self.stack[new_base]));
+                        error!(self, ErrorKind::ValueError(op, vec![self.stack[new_base].clone()]),
+                               "Tried to call non-function.");
                     }
                 }
             }
@@ -826,20 +821,23 @@ impl VM {
 mod tests {
     mod typing {
         use crate::error::ErrorKind;
-        use crate::test_string;
+        use crate::{test_string, Op, Type};
 
         test_string!(uncallable_type, "
                  f := fn i: int {
                      i()
                  }",
-                 [ErrorKind::TypeError(_, _)]);
+                 [ErrorKind::ValueError(Op::Call(0), _)]);
+
+        test_string!(invalid_assign, "a := 1\na = 0.1\n",
+                 [ErrorKind::TypeMismatch(Type::Int, Type::Float)]);
 
         test_string!(wrong_params, "
                  f : fn -> int = fn a: int -> int {}",
-                 [ErrorKind::TypeError(_, _), ErrorKind::TypeError(_, _)]);
+                 [ErrorKind::TypeMismatch(_, _), ErrorKind::TypeMismatch(Type::Void, Type::Int)]);
 
         test_string!(wrong_ret, "
                  f : fn -> int = fn {}",
-                 [ErrorKind::TypeError(_, _)]);
+                 [ErrorKind::TypeMismatch(_, _)]);
     }
 }