expr type inference, subscript slice needs to be removed, list comprehension needs to be fixed

This commit is contained in:
CrescentonC 2021-07-13 01:25:22 +08:00
parent 3dc448401b
commit 144b84a612
1 changed files with 347 additions and 199 deletions

View File

@ -1,11 +1,13 @@
use std::convert::TryInto; use std::convert::TryInto;
use crate::typecheck::context::InferenceContext; use crate::typecheck::context::InferenceContext;
use crate::typecheck::inference_core;
use crate::typecheck::magic_methods;
use crate::typecheck::typedef::{Type, TypeEnum}; use crate::typecheck::typedef::{Type, TypeEnum};
use crate::typecheck::primitives; use crate::typecheck::primitives;
use rustpython_parser::ast; use rustpython_parser::ast;
use super::magic_methods; use super::inference_core::resolve_call;
pub struct ExpressionTypeInferencer<'a> { pub struct ExpressionTypeInferencer<'a> {
pub ctx: InferenceContext<'a> //FIXME: may need to remove this pub pub ctx: InferenceContext<'a> //FIXME: may need to remove this pub
@ -94,6 +96,225 @@ impl<'a> ExpressionTypeInferencer<'a> { // NOTE: add location here in the functi
Err("tuple elements must have some type".into()) Err("tuple elements must have some type".into())
} }
} }
fn infer_arrtibute(&self, value: &Box<ast::Expr<Option<Type>>>, attr: &str) -> Result<Option<Type>, String> {
let ty = value.custom.clone().ok_or_else(|| "no value".to_string())?;
if let TypeEnum::TypeVariable(id) = ty.as_ref() {
let v = self.ctx.get_variable_def(*id);
if v.bound.is_empty() {
return Err("no fields on unbounded type variable".into());
}
let ty = v.bound[0].get_base(&self.ctx).and_then(|v| v.fields.get(attr));
if ty.is_none() {
return Err("unknown field".into());
}
for x in v.bound[1..].iter() {
let ty1 = x.get_base(&self.ctx).and_then(|v| v.fields.get(attr));
if ty1 != ty {
return Err("unknown field (type mismatch between variants)".into());
}
}
return Ok(Some(ty.unwrap().clone()));
}
match ty.get_base(&self.ctx) {
Some(b) => match b.fields.get(attr) {
Some(t) => Ok(Some(t.clone())),
None => Err("no such field".into()),
},
None => Err("this object has no fields".into()),
}
}
fn infer_bool_ops(&self, values: &Vec<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
assert_eq!(values.len(), 2);
let left = values[0].custom.clone().ok_or_else(|| "no value".to_string())?;
let right = values[1].custom.clone().ok_or_else(|| "no value".to_string())?;
let b = self.ctx.get_primitive(primitives::BOOL_TYPE);
if left == b && right == b {
Ok(Some(b))
} else {
Err("bool operands must be bool".to_string())
}
}
fn _infer_bin_ops(&self, _left: &Box<ast::Expr<Option<Type>>>, _op: &ast::Operator, _right: &Box<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
Err("no need this function".into())
}
fn infer_unary_ops(&self, op: &ast::Unaryop, operand: &Box<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
if let ast::Unaryop::Not = op {
if (**operand).custom == Some(self.ctx.get_primitive(primitives::BOOL_TYPE)) {
Ok(Some(self.ctx.get_primitive(primitives::BOOL_TYPE)))
} else {
Err("logical not must be applied to bool".into())
}
} else {
inference_core::resolve_call(&self.ctx, (**operand).custom.clone(), magic_methods::unaryop_name(op), &[])
}
}
fn infer_compare(&self, left: &Box<ast::Expr<Option<Type>>>, ops: &Vec<ast::Cmpop>, comparators: &Vec<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
assert!(comparators.len() > 0);
if left.custom.is_none() || (!comparators.iter().all(|x| x.custom.is_some())) {
Err("comparison operands must have type".into())
} else {
let bool_type = Some(self.ctx.get_primitive(primitives::BOOL_TYPE));
let ty_first = resolve_call(
&self.ctx,
Some(left.custom.clone().ok_or_else(|| "comparator must be able to be typed".to_string())?.clone()),
magic_methods::comparison_name(&ops[0]).ok_or_else(|| "unsupported comparison".to_string())?,
&[comparators[0].custom.clone().ok_or_else(|| "comparator must be able to be typed".to_string())?])?;
if ty_first != bool_type {
return Err("comparison result must be boolean".into());
}
for ((a, b), op)
in comparators[..(comparators.len() - 1)]
.iter()
.zip(comparators[1..].iter())
.zip(ops[1..].iter()) {
let ty = resolve_call(
&self.ctx,
Some(a.custom.clone().ok_or_else(|| "comparator must be able to be typed".to_string())?.clone()),
magic_methods::comparison_name(op).ok_or_else(|| "unsupported comparison".to_string())?,
&[b.custom.clone().ok_or_else(|| "comparator must be able to be typed".to_string())?.clone()])?;
if ty != bool_type {
return Err("comparison result must be boolean".into());
}
}
Ok(bool_type)
}
}
fn infer_call(&self, func: &Box<ast::Expr<Option<Type>>>, args: &Vec<ast::Expr<Option<Type>>>, _keywords: &Vec<ast::Keyword<Option<Type>>>) -> Result<Option<Type>, String> {
if args.iter().all(|x| x.custom.is_some()) {
match &func.node {
ast::ExprKind::Name {id, ctx: _}
=> resolve_call(
&self.ctx,
None,
id,
&args.iter().map(|x| x.custom.clone().unwrap()).collect::<Vec<_>>()),
ast::ExprKind::Attribute {value, attr, ctx: _}
=> resolve_call(
&self.ctx,
Some(value.custom.clone().ok_or_else(|| "no value".to_string())?),
&attr,
&args.iter().map(|x| x.custom.clone().unwrap()).collect::<Vec<_>>()),
_ => Err("not supported".into())
}
} else {
Err("function params must have type".into())
}
}
fn infer_slice(&self, lower: &Option<Box<ast::Expr<Option<Type>>>>, upper: &Option<Box<ast::Expr<Option<Type>>>>, step: &Option<Box<ast::Expr<Option<Type>>>>) -> Result<Option<Type>, String> {
let int32_type = self.ctx.get_primitive(primitives::INT32_TYPE);
let l = lower.as_ref().map_or(
Ok(&int32_type),
|x| x.custom.as_ref().ok_or("lower bound cannot be typped".to_string()))?;
let u = upper.as_ref().map_or(
Ok(&int32_type),
|x| x.custom.as_ref().ok_or("upper bound cannot be typped".to_string()))?;
let s = step.as_ref().map_or(
Ok(&int32_type),
|x| x.custom.as_ref().ok_or("step cannot be typped".to_string()))?;
if l == &int32_type && u == &int32_type && s == &int32_type {
Ok(Some(self.ctx.get_primitive(primitives::SLICE_TYPE)))
} else {
Err("slice must be int32 type".into())
}
}
fn infer_subscript(&self, value: &Box<ast::Expr<Option<Type>>>, slice: &Box<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
// let tt = value.custom.ok_or_else(|| "no value".to_string())?.as_ref();
let t = if let TypeEnum::ParametricType(primitives::LIST_TYPE, ls) = value.custom.as_ref().ok_or_else(|| "no value".to_string())?.as_ref() {
ls[0].clone()
} else {
return Err("subscript is not supported for types other than list".into());
};
if slice.custom == Some(self.ctx.get_primitive(primitives::SLICE_TYPE)) {
Ok(value.custom.clone())
} else if slice.custom == Some(self.ctx.get_primitive(primitives::INT32_TYPE)) {
Ok(Some(t))
} else {
Err("slice or index must be int32 type".into())
}
}
fn infer_if_expr(&self, test: &Box<ast::Expr<Option<Type>>>, body: &Box<ast::Expr<Option<Type>>>, orelse: &Box<ast::Expr<Option<Type>>>) -> Result<Option<Type>, String> {
if test.custom != Some(self.ctx.get_primitive(primitives::BOOL_TYPE)) {
Err("test should be bool".into())
} else {
if body.custom == orelse.custom {
Ok(body.custom.clone())
} else {
Err("divergent type at if expression".into())
}
}
}
fn infer_simple_binding(&mut self, name: &'a ast::Expr<Option<Type>>, ty: Type) -> Result<(), String> {
match &name.node {
ast::ExprKind::Name {id, ctx: _} => {
if id == "_" {
Ok(())
} else if self.ctx.defined(id.as_str()) {
Err("duplicated naming".into())
} else {
self.ctx.assign(id.as_str(), ty, name.location)?;
Ok(())
}
}
ast::ExprKind::Tuple {elts, ctx: _} => {
if let TypeEnum::ParametricType(TUPLE_TYPE, ls) = ty.as_ref() {
if elts.len() == ls.len() {
for (a, b) in elts.iter().zip(ls.iter()) {
self.infer_simple_binding(a, b.clone())?;
}
Ok(())
} else {
Err("different length".into())
}
} else {
Err("not supported".into())
}
}
_ => Err("not supported".into())
}
}
fn infer_list_comprehesion(&mut self, elt: &Box<ast::Expr<Option<Type>>>, generators: &Vec<ast::Comprehension<Option<Type>>>) -> Result<Option<Type>, String> {
if generators.len() != 1 {
Err("only 1 generator statement is supported".into())
} else {
let gen = &generators[0];
if gen.is_async {
Err("async is not supported".into())
} else {
let iter_type = gen.iter.custom.as_ref().ok_or("no value".to_string())?.as_ref();
if let TypeEnum::ParametricType(primitives::LIST_TYPE, ref ls) = iter_type {
self.ctx.with_scope(|x| {
// x.infer_simple_binding(&gen.target, ls[0].clone()); // FIXME:
Ok(None)
}).1
} else {
Err("iteration is supported for list only".into())
}
}
}
}
} }
// REVIEW: field custom: from () to Option<Type> or just Option<Type>? // REVIEW: field custom: from () to Option<Type> or just Option<Type>?
@ -105,217 +326,144 @@ impl<'a> ast::fold::Fold<Option<Type>> for ExpressionTypeInferencer<'a> {
Ok(user) Ok(user)
} }
fn fold_expr(&mut self, expr: ast::Expr<Option<Type>>) -> Result<ast::Expr<Self::TargetU>, Self::Error> { // override the default fold_comprehension to avoid errors caused by folding locally bound variable
let ast::Expr {location, custom, node} = expr; fn fold_comprehension(&mut self, node: ast::Comprehension<Option<Type>>) -> Result<ast::Comprehension<Self::TargetU>, Self::Error> {
match node { Ok(ast::Comprehension {
ast::ExprKind::Constant {value, kind} => target: node.target,
Ok(ast::Expr { iter: Box::new(self.fold_expr(*node.iter)?),
location, ifs: node.ifs,
custom: self.infer_constant_val(&value)?, is_async: node.is_async
node: ast::ExprKind::Constant {value, kind} })
}
fn fold_expr(&mut self, node: ast::Expr<Option<Type>>) -> Result<ast::Expr<Self::TargetU>, Self::Error> {
assert_eq!(node.custom, None); // NOTE: should pass
let mut expr = node;
if let ast::Expr {location: _, custom: _, node: ast::ExprKind::ListComp {elt, generators } } = expr {
expr = ast::Expr {
location: expr.location,
custom: expr.custom,
node: ast::ExprKind::ListComp {
elt,
generators: generators.into_iter().map(|x| self.fold_comprehension(x)).collect::<Result<Vec<_>, _>>()?
}
};
} else {
// if not listcomp which requires special handling, skip current level, make sure child nodes have their type
expr = ast::fold::fold_expr(self, expr)?;
}
match &expr.node {
ast::ExprKind::Constant {value, kind: _} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_constant_val(value)?,
node: expr.node
}), }),
ast::ExprKind::Name {id, ctx} => ast::ExprKind::Name {id, ctx: _} =>
Ok(ast::Expr { Ok(ast::Expr {
location, location: expr.location,
custom: Some(self.ctx.resolve(&*id)?), // REVIEW: the conversion from String to &str is not sure custom: Some(self.ctx.resolve(id)?),
node: ast::ExprKind::Name {id, ctx} node: expr.node
}), }),
ast::ExprKind::List {elts, ctx} => { ast::ExprKind::List {elts, ctx: _} => {
/* let folded = ast::fold::fold_expr(
self,
ast::Expr {location, custom, node: ast::ExprKind::List {elts, ctx}})?;
if let ast::Expr {location: _, custom: _, node: ast::ExprKind::List {elts, ctx}} = folded {
Ok(ast::Expr {
location,
custom: self.infer_list_val(&elts)?,
node: ast::ExprKind::List {elts, ctx}
})
} else {
Err("something wrong here".into())
} */
let elts = elts
.into_iter()
.map(|x| self.fold_expr(x))
.collect::<Result<Vec<ast::Expr<Option<Type>>>, _>>()?; // elements inside the vector should now have type info
Ok(ast::Expr { Ok(ast::Expr {
location, location: expr.location,
custom: self.infer_list_val(&elts)?, custom: self.infer_list_val(elts)?,
node: ast::ExprKind::List {elts, ctx} node: expr.node
}) })
} }
ast::ExprKind::Tuple {elts, ctx} => { ast::ExprKind::Tuple {elts, ctx: _} =>
// let folded_tup_expr = ast::fold::fold_expr(self, ast::Expr {location, custom, node})?;
let elts= elts
.into_iter()
.map(|x| self.fold_expr(x))
.collect::<Result<Vec<ast::Expr<Option<Type>>>, _>>()?; // elements inside the vector should now have type info
Ok(ast::Expr { Ok(ast::Expr {
location, location: expr.location,
custom: self.infer_tuple_val(&elts)?, custom: self.infer_tuple_val(elts)?,
node: ast::ExprKind::Tuple {elts, ctx} node: expr.node
}) }),
}
ast::ExprKind::Attribute {value, attr, ctx} => {
let folded_val = self.fold_expr(*value)?;
match folded_val.custom {
Some(ref ty) => {
if let TypeEnum::TypeVariable(_) = ty.as_ref() {
Err("no fields for type variable".into())
} else {
ty
.clone()
.get_base(&self.ctx)
.and_then(|b| b.fields.get(&*attr).clone())
.map_or_else(
|| Err("no such field".into()),
|v| Ok(ast::Expr {
location,
custom: Some(v.clone()),
node: ast::ExprKind::Attribute {value: Box::new(folded_val), attr, ctx}
}))
}
},
None => Err("no value".into())
}
}
ast::ExprKind::BoolOp {op, values} => {
assert_eq!(values.len(), 2); // NOTE: should panic
let folded = values
.into_iter()
.map(|x| self.fold_expr(x))
.collect::<Result<Vec<ast::Expr<Option<Type>>>, _>>()?;
if (&folded)
.iter()
.all(|x| x.custom == Some(self.ctx.get_primitive(primitives::BOOL_TYPE))) {
Ok(ast::Expr {
location,
node: ast::ExprKind::BoolOp {op, values: folded},
custom: Some(self.ctx.get_primitive(primitives::BOOL_TYPE))
})
} else {
Err("bool operands must be bool".into())
}
}
ast::ExprKind::BinOp {op, left, right} => {
let folded_left = self.fold_expr(*left)?;
let folded_right = self.fold_expr(*right)?;
let fun = magic_methods::binop_name(&op);
let left_type = folded_left.custom.clone().ok_or_else(|| "no value".to_string())?;
let right_type = folded_right.custom.clone().ok_or_else(|| "no value".to_string())?;
let result = crate::typecheck::inference_core::resolve_call(
&self.ctx,
Some(left_type),
fun,
&[right_type])?;
ast::ExprKind::Attribute {value, attr, ctx: _} =>
Ok(ast::Expr { Ok(ast::Expr {
location, location: expr.location,
custom: result, custom: self.infer_arrtibute(value, attr)?,
node: ast::ExprKind::BinOp {op, left: Box::new(folded_left), right: Box::new(folded_right)} node: expr.node
}) }),
ast::ExprKind::BoolOp {op: _, values} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_bool_ops(values)?,
node: expr.node
}),
ast::ExprKind::BinOp {left, op, right} =>
Ok(ast::Expr {
location: expr.location,
custom: inference_core::resolve_call(
&self.ctx,
Some(left.custom.clone().ok_or_else(|| "no value".to_string())?),
magic_methods::binop_name(op),
&[right.custom.clone().ok_or_else(|| "no value".to_string())?])?,
node: expr.node
}),
ast::ExprKind::UnaryOp {op, operand} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_unary_ops(op, operand)?,
node: expr.node
}),
ast::ExprKind::Compare {left, ops, comparators} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_compare(left, ops, comparators)?,
node: expr.node
}),
ast::ExprKind::Call {func, args, keywords} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_call(func, args, keywords)?,
node: expr.node
}),
// REVIEW: add a new primitive type for slice and do type check of bounds here?
ast::ExprKind::Slice {lower, upper, step } =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_slice(lower, upper, step)?,
node: expr.node
}),
ast::ExprKind::Subscript {value, slice, ctx} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_subscript(value, slice)?,
node: expr.node
}),
ast::ExprKind::IfExp {test, body, orelse} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_if_expr(test, body, orelse)?,
node: expr.node
}),
ast::ExprKind::ListComp {elt, generators} =>
Ok(ast::Expr {
location: expr.location,
custom: self.infer_list_comprehesion(elt, generators)?,
node: expr.node
}),
_ => { // not supported
Err("not supported yet".into())
} }
ast::ExprKind::UnaryOp {op, operand} => {
let folded = self.fold_expr(*operand)?;
let ty = folded.custom.clone().ok_or_else(|| "no value".to_string())?;
if let ast::Unaryop::Not = op {
if ty == self.ctx.get_primitive(primitives::BOOL_TYPE) {
Ok(ast::Expr {
location,
node: ast::ExprKind::UnaryOp {op, operand: Box::new(folded)},
custom: Some(self.ctx.get_primitive(primitives::BOOL_TYPE))
})
} else {
Err("logical not must be applied to bool".into())
}
} else {
Ok(ast::Expr {
location,
custom: crate::typecheck::inference_core::resolve_call(
&self.ctx,
Some(ty),
magic_methods::unaryop_name(&op),
&[])?,
node: ast::ExprKind::UnaryOp {op, operand: Box::new(folded)},
})
}
}
ast::ExprKind::Compare {left, ops, comparators} => {
Err("not sure".into()) // FIXME: what is the `left` field here?
}
ast::ExprKind::Call {func, args, keywords} => {
if !keywords.is_empty() {
Err("keyword is not supported yet".into())
} else {
let folded_args = args
.into_iter()
.map(|x| self.fold_expr(x))
.collect::<Result<Vec<ast::Expr<Option<Type>>>, _>>()?;
if !folded_args.iter().all(|x| x.custom.is_some()) {
Err("function params must have type".into())
} else {
match &func.node {
ast::ExprKind::Name {id, ctx} => {
Ok(ast::Expr {
location,
custom: crate::typecheck::inference_core::resolve_call(
&self.ctx,
None,
id,
&folded_args
.iter()
.map(|x| (x.custom.clone().unwrap()))
.collect::<Vec<_>>())?,
node: ast::ExprKind::Call {func, args: folded_args, keywords}
})
}
ast::ExprKind::Attribute {value, attr, ctx} => {
// Err("sdf".into())
let folded_value = self.fold_expr(**value)?;
Ok(ast::Expr {
location,
node: ast::ExprKind::Call {func, args: folded_args, keywords},
custom: crate::typecheck::inference_core::resolve_call(
&self.ctx,
folded_value.custom,
attr,
&folded_args
.iter()
.map(|x| (x.custom.clone().unwrap()))
.collect::<Vec<_>>())?
})
}
_ => Err("not supported".into())
}
// Err("sdf".into())
}
}
}
_ =>
Ok(ast::Expr {location, custom, node})
} }
} }
} }