If an error message is emitted that spans several files, only the
primary file currently has line and column data attached. This is
useful information, even in files other than the one in which the error
occurs. We can often work out which line and column the error
corresponds to in other files — in this case it is helpful to add them
(in the case of ambiguity, the first relevant line/column is picked,
which is still helpful than none).
When a span starts on a line with nothing but whitespace to the left,
and there are no other annotations in that line, simplify the visual
representation of the span.
Go from:
```rust
error[E0072]: recursive type `A` has infinite size
--> file2.rs:1:1
|
1 | struct A {
| _^ starting here...
2 | | a: A,
3 | | }
| |_^ ...ending here: recursive type has infinite size
|
```
To:
```rust
error[E0072]: recursive type `A` has infinite size
--> file2.rs:1:1
|
1 | / struct A {
2 | | a: A,
3 | | }
| |_^ recursive type has infinite size
```
Remove `starting here...`/`...ending here` labels from all multiline
diagnostics.
Fix multiple labels when some don't have message
The diagnostic emitter now accounts for labels with no text message, presenting the underline on its own, without drawing the line for the non existing message below it. Go from
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ----^^^^^^^----
| | |
| | `b` is a good letter
|
```
to
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ----^^^^^^^----
| |
| `b` is a good letter
```
from
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^
| | |
| |
| `a` is a good letter
```
to
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^ `a` is a good letter
```
and from
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^
| | |
| |
|
```
to
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^
```
r? @nikomatsakis
cc @jonathandturner, @GuillaumeGomez, @nrc
The diagnostic emitter now accounts for labels with no text message,
presenting the underline on its own, without drawing the line for the
non existing message below it. Go from
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ----^^^^^^^----
| | |
| | `b` is a good letter
|
```
to
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ----^^^^^^^----
| |
| `b` is a good letter
```
and from
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^
| | |
| |
| `a` is a good letter
```
to
```
error: foo
--> test.rs:3:6
|
3 | a { b { c } d }
| ^^^^-------^^^^ `a` is a good letter
```
When dealing with multiline spans that span few lines, show the complete
span instead of restricting to the first character of the first line.
For example, instead of:
```
% ./rustc foo.rs
error[E0277]: the trait bound `{integer}: std::ops::Add<()>` is not satisfied
--> foo.rs:13:9
|
13 | foo(1 + bar(x,
| ^ trait `{integer}: std::ops::Add<()>` not satisfied
|
```
show
```
% ./rustc foo.rs
error[E0277]: the trait bound `{integer}: std::ops::Add<()>` is not satisfied
--> foo.rs:13:9
|
13 | foo(1 + bar(x,
| ________^ starting here...
14 | | y),
| |_____________^ ...ending here: trait `{integer}: std::ops::Add<()>` not satisfied
|
```
