Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add suggestion for incorrect field syntax. #57863

Merged
merged 1 commit into from
Jan 25, 2019
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 17 additions & 1 deletion src/libsyntax/parse/parser.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2263,8 +2263,24 @@ impl<'a> Parser<'a> {
let lo = self.span;

// Check if a colon exists one ahead. This means we're parsing a fieldname.
let (fieldname, expr, is_shorthand) = if self.look_ahead(1, |t| t == &token::Colon) {
let (fieldname, expr, is_shorthand) = if self.look_ahead(1, |t| {
t == &token::Colon || t == &token::Eq
}) {
let fieldname = self.parse_field_name()?;

// Check for an equals token. This means the source incorrectly attempts to
// initialize a field with an eq rather than a colon.
if self.token == token::Eq {
self.diagnostic()
.struct_span_err(self.span, "expected `:`, found `=`")
.span_suggestion_with_applicability(
fieldname.span.shrink_to_hi().to(self.span),
"replace equals symbol with a colon",
":".to_string(),
Applicability::MachineApplicable,
)
.emit();
}
self.bump(); // `:`
(fieldname, self.parse_expr()?, false)
} else {
Expand Down
37 changes: 37 additions & 0 deletions src/test/ui/issues/issue-57684.fixed
Original file line number Diff line number Diff line change
@@ -0,0 +1,37 @@
// run-rustfix

#![allow(warnings)]

// This test checks that the following error is emitted when a `=` character is used to initialize
// a struct field when a `:` is expected.
//
// ```
// error: struct fields are initialized with a colon
// --> $DIR/issue-57684.rs:12:20
// |
// LL | let _ = X { f1 = 5 };
// | ^ help: replace equals symbol with a colon: `:`
// ```

struct X {
f1: i32,
}

struct Y {
f1: i32,
f2: i32,
f3: i32,
}

fn main() {
let _ = X { f1: 5 };
//~^ ERROR expected `:`, found `=`

let f3 = 3;
let _ = Y {
f1: 5,
//~^ ERROR expected `:`, found `=`
f2: 4,
f3,
};
}
37 changes: 37 additions & 0 deletions src/test/ui/issues/issue-57684.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,37 @@
// run-rustfix

#![allow(warnings)]

// This test checks that the following error is emitted when a `=` character is used to initialize
// a struct field when a `:` is expected.
//
// ```
// error: struct fields are initialized with a colon
// --> $DIR/issue-57684.rs:12:20
// |
// LL | let _ = X { f1 = 5 };
// | ^ help: replace equals symbol with a colon: `:`
// ```

struct X {
f1: i32,
}

struct Y {
f1: i32,
f2: i32,
f3: i32,
}

fn main() {
let _ = X { f1 = 5 };
//~^ ERROR expected `:`, found `=`

let f3 = 3;
let _ = Y {
f1 = 5,
//~^ ERROR expected `:`, found `=`
f2: 4,
f3,
};
}
18 changes: 18 additions & 0 deletions src/test/ui/issues/issue-57684.stderr
Original file line number Diff line number Diff line change
@@ -0,0 +1,18 @@
error: expected `:`, found `=`
--> $DIR/issue-57684.rs:27:20
|
LL | let _ = X { f1 = 5 };
| -^
| |
| help: replace equals symbol with a colon: `:`

error: expected `:`, found `=`
--> $DIR/issue-57684.rs:32:12
|
LL | f1 = 5,
| -^
| |
| help: replace equals symbol with a colon: `:`

error: aborting due to 2 previous errors