Standardize lifetime and type parameter count mismatch errors

They now always say how many lifetime / type parameters were expected
and are explicit about stating "lifetime" or "type" instead of just
"parameter".
This commit is contained in:
Jake Goulding 2017-02-12 20:29:51 -05:00
parent 79d32e9948
commit 1c998416ee
6 changed files with 42 additions and 30 deletions

View File

@ -4510,28 +4510,32 @@ fn check_path_parameter_count(&self,
}
};
let count = |n| {
format!("{} parameter{}", n, if n == 1 { "" } else { "s" })
let count_lifetime_params = |n| {
format!("{} lifetime parameter{}", n, if n == 1 { "" } else { "s" })
};
let count_type_params = |n| {
format!("{} type parameter{}", n, if n == 1 { "" } else { "s" })
};
// Check provided lifetime parameters.
let lifetime_defs = segment.map_or(&[][..], |(_, generics)| &generics.regions);
if lifetimes.len() > lifetime_defs.len() {
let expected_text = count_lifetime_params(lifetime_defs.len());
let actual_text = count_lifetime_params(lifetimes.len());
struct_span_err!(self.tcx.sess, span, E0088,
"too many lifetime parameters provided: \
expected {}, found {}",
count(lifetime_defs.len()),
count(lifetimes.len()))
.span_label(span, &format!("unexpected lifetime parameter{}",
match lifetimes.len() { 1 => "", _ => "s" }))
expected at most {}, found {}",
expected_text, actual_text)
.span_label(span, &format!("expected {}", expected_text))
.emit();
} else if lifetimes.len() > 0 && lifetimes.len() < lifetime_defs.len() {
let expected_text = count_lifetime_params(lifetime_defs.len());
let actual_text = count_lifetime_params(lifetimes.len());
struct_span_err!(self.tcx.sess, span, E0090,
"too few lifetime parameters provided: \
expected {}, found {}",
count(lifetime_defs.len()),
count(lifetimes.len()))
.span_label(span, &format!("too few lifetime parameters"))
expected_text, actual_text)
.span_label(span, &format!("expected {}", expected_text))
.emit();
}
@ -4552,26 +4556,27 @@ fn check_path_parameter_count(&self,
.count();
if types.len() > type_defs.len() {
let span = types[type_defs.len()].span;
let expected_text = count_type_params(type_defs.len());
let actual_text = count_type_params(types.len());
struct_span_err!(self.tcx.sess, span, E0087,
"too many type parameters provided: \
expected at most {}, found {}",
count(type_defs.len()),
count(types.len()))
.span_label(span, &format!("too many type parameters")).emit();
expected_text, actual_text)
.span_label(span, &format!("expected {}", expected_text))
.emit();
// To prevent derived errors to accumulate due to extra
// type parameters, we force instantiate_value_path to
// use inference variables instead of the provided types.
*segment = None;
} else if !infer_types && types.len() < required_len {
let adjust = |len| if len > 1 { "parameters" } else { "parameter" };
let required_param_str = adjust(required_len);
let expected_text = count_type_params(required_len);
let actual_text = count_type_params(types.len());
struct_span_err!(self.tcx.sess, span, E0089,
"too few type parameters provided: \
expected {}, found {}",
count(required_len),
count(types.len()))
.span_label(span, &format!("expected {} type {}", required_len, required_param_str))
expected_text, actual_text)
.span_label(span, &format!("expected {}", expected_text))
.emit();
}

View File

@ -8,9 +8,13 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
fn foo<T>() {}
fn foo() {}
fn bar<T>() {}
fn main() {
foo::<f64, bool>(); //~ ERROR E0087
//~^ NOTE too many type parameters
foo::<f64>(); //~ ERROR expected at most 0 type parameters, found 1 type parameter [E0087]
//~^ NOTE expected 0 type parameters
bar::<f64, u64>(); //~ ERROR expected at most 1 type parameter, found 2 type parameters [E0087]
//~^ NOTE expected 1 type parameter
}

View File

@ -12,9 +12,11 @@ fn f() {}
fn g<'a>() {}
fn main() {
f::<'static>(); //~ ERROR E0088
//~^ unexpected lifetime parameter
f::<'static>();
//~^ ERROR expected at most 0 lifetime parameters, found 1 lifetime parameter [E0088]
//~| NOTE expected 0 lifetime parameters
g::<'static, 'static>(); //~ ERROR E0088
//~^ unexpected lifetime parameters
g::<'static, 'static>();
//~^ ERROR expected at most 0 lifetime parameters, found 2 lifetime parameters [E0088]
//~| NOTE expected 0 lifetime parameters
}

View File

@ -11,6 +11,6 @@
fn foo<T, U>() {}
fn main() {
foo::<f64>(); //~ ERROR expected 2 parameters, found 1 parameter [E0089]
foo::<f64>(); //~ ERROR expected 2 type parameters, found 1 type parameter [E0089]
//~| NOTE expected 2 type parameters
}

View File

@ -9,7 +9,8 @@
// except according to those terms.
fn foo<'a: 'b, 'b: 'a>() {}
fn main() {
foo::<'static>();//~ ERROR E0090
//~^ too few lifetime parameters
foo::<'static>(); //~ ERROR expected 2 lifetime parameters, found 1 lifetime parameter [E0090]
//~^ NOTE expected 2 lifetime parameters
}

View File

@ -22,5 +22,5 @@ fn into_cow(self) -> Cow<'a, str> {
fn main() {
<String as IntoCow>::into_cow("foo".to_string());
//~^ ERROR too few type parameters provided: expected 1 parameter
//~^ ERROR too few type parameters provided: expected 1 type parameter
}