Modify spans of expanded expression

Modify the spans used for `for`-loop expression expansion, instead of
creating a new span during error creation.
This commit is contained in:
Esteban Küber 2018-01-25 14:07:45 -08:00
parent 3a530baec9
commit f90c445637
6 changed files with 38 additions and 58 deletions

View File

@ -3021,7 +3021,7 @@ impl<'a> LoweringContext<'a> {
// `match <sub_expr> { ... }` // `match <sub_expr> { ... }`
let arms = hir_vec![pat_arm, break_arm]; let arms = hir_vec![pat_arm, break_arm];
let match_expr = self.expr(e.span, let match_expr = self.expr(sub_expr.span,
hir::ExprMatch(sub_expr, hir::ExprMatch(sub_expr,
arms, arms,
hir::MatchSource::WhileLetDesugar), hir::MatchSource::WhileLetDesugar),
@ -3059,24 +3059,25 @@ impl<'a> LoweringContext<'a> {
// expand <head> // expand <head>
let head = self.lower_expr(head); let head = self.lower_expr(head);
let head_sp = head.span;
let iter = self.str_to_ident("iter"); let iter = self.str_to_ident("iter");
let next_ident = self.str_to_ident("__next"); let next_ident = self.str_to_ident("__next");
let next_pat = self.pat_ident_binding_mode(e.span, let next_pat = self.pat_ident_binding_mode(pat.span,
next_ident, next_ident,
hir::BindingAnnotation::Mutable); hir::BindingAnnotation::Mutable);
// `::std::option::Option::Some(val) => next = val` // `::std::option::Option::Some(val) => next = val`
let pat_arm = { let pat_arm = {
let val_ident = self.str_to_ident("val"); let val_ident = self.str_to_ident("val");
let val_pat = self.pat_ident(e.span, val_ident); let val_pat = self.pat_ident(pat.span, val_ident);
let val_expr = P(self.expr_ident(e.span, val_ident, val_pat.id)); let val_expr = P(self.expr_ident(pat.span, val_ident, val_pat.id));
let next_expr = P(self.expr_ident(e.span, next_ident, next_pat.id)); let next_expr = P(self.expr_ident(pat.span, next_ident, next_pat.id));
let assign = P(self.expr(e.span, let assign = P(self.expr(pat.span,
hir::ExprAssign(next_expr, val_expr), hir::ExprAssign(next_expr, val_expr),
ThinVec::new())); ThinVec::new()));
let some_pat = self.pat_some(e.span, val_pat); let some_pat = self.pat_some(pat.span, val_pat);
self.arm(hir_vec![some_pat], assign) self.arm(hir_vec![some_pat], assign)
}; };
@ -3089,46 +3090,45 @@ impl<'a> LoweringContext<'a> {
}; };
// `mut iter` // `mut iter`
let iter_pat = self.pat_ident_binding_mode(e.span, let iter_pat = self.pat_ident_binding_mode(head_sp,
iter, iter,
hir::BindingAnnotation::Mutable); hir::BindingAnnotation::Mutable);
// `match ::std::iter::Iterator::next(&mut iter) { ... }` // `match ::std::iter::Iterator::next(&mut iter) { ... }`
let match_expr = { let match_expr = {
let iter = P(self.expr_ident(e.span, iter, iter_pat.id)); let iter = P(self.expr_ident(head_sp, iter, iter_pat.id));
let ref_mut_iter = self.expr_mut_addr_of(e.span, iter); let ref_mut_iter = self.expr_mut_addr_of(head_sp, iter);
let next_path = &["iter", "Iterator", "next"]; let next_path = &["iter", "Iterator", "next"];
let next_path = P(self.expr_std_path(e.span, next_path, ThinVec::new())); let next_path = P(self.expr_std_path(head_sp, next_path, ThinVec::new()));
let next_expr = P(self.expr_call(e.span, next_path, let next_expr = P(self.expr_call(head_sp, next_path,
hir_vec![ref_mut_iter])); hir_vec![ref_mut_iter]));
let arms = hir_vec![pat_arm, break_arm]; let arms = hir_vec![pat_arm, break_arm];
P(self.expr(e.span, P(self.expr(head_sp,
hir::ExprMatch(next_expr, arms, hir::ExprMatch(next_expr, arms,
hir::MatchSource::ForLoopDesugar), hir::MatchSource::ForLoopDesugar),
ThinVec::new())) ThinVec::new()))
}; };
let match_stmt = respan(e.span, hir::StmtExpr(match_expr, self.next_id().node_id)); let match_stmt = respan(head_sp, hir::StmtExpr(match_expr, self.next_id().node_id));
let next_expr = P(self.expr_ident(e.span, next_ident, next_pat.id)); let next_expr = P(self.expr_ident(head_sp, next_ident, next_pat.id));
// `let mut __next` // `let mut __next`
let next_let = self.stmt_let_pat(e.span, let next_let = self.stmt_let_pat(head_sp,
None, None,
next_pat, next_pat,
hir::LocalSource::ForLoopDesugar); hir::LocalSource::ForLoopDesugar);
// `let <pat> = __next` // `let <pat> = __next`
let pat = self.lower_pat(pat); let pat = self.lower_pat(pat);
let pat_let = self.stmt_let_pat(e.span, let pat_let = self.stmt_let_pat(head_sp,
Some(next_expr), Some(next_expr),
pat, pat,
hir::LocalSource::ForLoopDesugar); hir::LocalSource::ForLoopDesugar);
let body_block = self.with_loop_scope(e.id, let body_block = self.with_loop_scope(e.id, |this| this.lower_block(body, false));
|this| this.lower_block(body, false));
let body_expr = P(self.expr_block(body_block, ThinVec::new())); let body_expr = P(self.expr_block(body_block, ThinVec::new()));
let body_stmt = respan(e.span, hir::StmtExpr(body_expr, self.next_id().node_id)); let body_stmt = respan(body.span, hir::StmtExpr(body_expr, self.next_id().node_id));
let loop_block = P(self.block_all(e.span, let loop_block = P(self.block_all(e.span,
hir_vec![next_let, hir_vec![next_let,
@ -3155,12 +3155,12 @@ impl<'a> LoweringContext<'a> {
// `match ::std::iter::IntoIterator::into_iter(<head>) { ... }` // `match ::std::iter::IntoIterator::into_iter(<head>) { ... }`
let into_iter_expr = { let into_iter_expr = {
let into_iter_path = &["iter", "IntoIterator", "into_iter"]; let into_iter_path = &["iter", "IntoIterator", "into_iter"];
let into_iter = P(self.expr_std_path(e.span, into_iter_path, let into_iter = P(self.expr_std_path(head_sp, into_iter_path,
ThinVec::new())); ThinVec::new()));
P(self.expr_call(e.span, into_iter, hir_vec![head])) P(self.expr_call(head_sp, into_iter, hir_vec![head]))
}; };
let match_expr = P(self.expr_match(e.span, let match_expr = P(self.expr_match(head_sp,
into_iter_expr, into_iter_expr,
hir_vec![iter_arm], hir_vec![iter_arm],
hir::MatchSource::ForLoopDesugar)); hir::MatchSource::ForLoopDesugar));

View File

@ -551,24 +551,6 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
let OnUnimplementedNote { message, label } let OnUnimplementedNote { message, label }
= self.on_unimplemented_note(trait_ref, obligation); = self.on_unimplemented_note(trait_ref, obligation);
let have_alt_message = message.is_some() || label.is_some(); let have_alt_message = message.is_some() || label.is_some();
let span = match self.tcx.sess.codemap().span_to_snippet(span) {
Ok(ref s) if s.starts_with("for ") => {
// On for loops, this error is caused by the element being iterated
// on, but the span points at the entire for loop. Instead of:
//
// / for c in "asdf" {
// | ...
// | }
// |_^ `&str` is not an iterator
//
// lets point at:
//
// for c in "asdf" {
// ^^^^^^^^^^^^^^^ `&str` is not an iterator
self.tcx.sess.codemap().span_until_char(span, '{')
}
_ => span,
};
let mut err = struct_span_err!( let mut err = struct_span_err!(
self.tcx.sess, self.tcx.sess,

View File

@ -10,7 +10,7 @@
fn changer<'a>(mut things: Box<Iterator<Item=&'a mut u8>>) { fn changer<'a>(mut things: Box<Iterator<Item=&'a mut u8>>) {
for item in *things { *item = 0 } for item in *things { *item = 0 }
//~^ ERROR `std::iter::Iterator<Item=&mut u8>: std::marker::Sized` is not satisfied //~^ ERROR the trait bound `std::iter::Iterator<Item=&mut u8>: std::marker::Sized` is not satisfied
} }
fn main() {} fn main() {}

View File

@ -13,22 +13,20 @@ error[E0016]: blocks in constant functions are limited to items and tail express
| ^ | ^
error[E0015]: calls in constant functions are limited to constant functions, struct and enum constructors error[E0015]: calls in constant functions are limited to constant functions, struct and enum constructors
--> $DIR/const-fn-error.rs:17:5 --> $DIR/const-fn-error.rs:17:14
| |
17 | / for i in 0..x { //~ ERROR calls in constant functions 17 | for i in 0..x { //~ ERROR calls in constant functions
18 | | //~| ERROR constant function contains unimplemented | ^^^^
19 | | sum += i; | |
20 | | } | in this macro invocation
| |_____^
error[E0019]: constant function contains unimplemented expression type error[E0019]: constant function contains unimplemented expression type
--> $DIR/const-fn-error.rs:17:5 --> $DIR/const-fn-error.rs:17:14
| |
17 | / for i in 0..x { //~ ERROR calls in constant functions 17 | for i in 0..x { //~ ERROR calls in constant functions
18 | | //~| ERROR constant function contains unimplemented | ^^^^
19 | | sum += i; | |
20 | | } | in this macro invocation
| |_____^
error[E0080]: constant evaluation error error[E0080]: constant evaluation error
--> $DIR/const-fn-error.rs:21:5 --> $DIR/const-fn-error.rs:21:5

View File

@ -8,10 +8,10 @@ error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _,
found type `&_` found type `&_`
error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _, _> as std::iter::Iterator>::Item == &_` error[E0271]: type mismatch resolving `<std::collections::hash_map::Iter<'_, _, _> as std::iter::Iterator>::Item == &_`
--> $DIR/issue-33941.rs:14:5 --> $DIR/issue-33941.rs:14:14
| |
14 | for _ in HashMap::new().iter().cloned() {} //~ ERROR type mismatch 14 | for _ in HashMap::new().iter().cloned() {} //~ ERROR type mismatch
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected tuple, found reference | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected tuple, found reference
| |
= note: expected type `(&_, &_)` = note: expected type `(&_, &_)`
found type `&_` found type `&_`

View File

@ -1,8 +1,8 @@
error[E0277]: the trait bound `&str: std::iter::Iterator` is not satisfied error[E0277]: the trait bound `&str: std::iter::Iterator` is not satisfied
--> $DIR/for-c-in-str.rs:14:5 --> $DIR/for-c-in-str.rs:14:14
| |
14 | for c in "asdf" { 14 | for c in "asdf" {
| ^^^^^^^^^^^^^^^ `&str` is not an iterator; maybe try calling `.iter()` or a similar method | ^^^^^^ `&str` is not an iterator; maybe try calling `.iter()` or a similar method
| |
= help: the trait `std::iter::Iterator` is not implemented for `&str` = help: the trait `std::iter::Iterator` is not implemented for `&str`
= note: required by `std::iter::IntoIterator::into_iter` = note: required by `std::iter::IntoIterator::into_iter`