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Specific error for positional args after named args in format!()

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When writing positional arguments after named arguments in the
`format!()` and `println!()` macros, provide a targeted diagnostic.
This commit is contained in:
Esteban Küber 2019-07-15 20:51:32 -07:00
parent 4b65a86eba
commit 33ec1823d7
5 changed files with 53 additions and 34 deletions
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2
src/test/ui/if/ifmt-bad-arg.rs
View file

@ -38,7 +38,7 @@ fn main() {
format!("{} {}", 1, 2, foo=1, bar=2); //~ ERROR: multiple unused formatting arguments
format!("{foo}", foo=1, foo=2); //~ ERROR: duplicate argument
format!("", foo=1, 2); //~ ERROR: positional arguments cannot follow
format!("{foo} {} {}", foo=1, 2); //~ ERROR: positional arguments cannot follow
// bad named arguments, #35082

10
src/test/ui/if/ifmt-bad-arg.stderr
View file

@ -146,11 +146,13 @@ note: previously here
LL | format!("{foo}", foo=1, foo=2);
| ^
error: expected ident, positional arguments cannot follow named arguments
--> $DIR/ifmt-bad-arg.rs:41:24
error: positional arguments cannot follow named arguments
--> $DIR/ifmt-bad-arg.rs:41:35
|
LL | format!("", foo=1, 2);
| ^
LL | format!("{foo} {} {}", foo=1, 2);
| - ^ positional arguments must be before named arguments
| |
| named argument
error: there is no argument named `valueb`
--> $DIR/ifmt-bad-arg.rs:45:23

10
src/test/ui/macros/format-parse-errors.rs
View file

@ -1,9 +1,15 @@
fn main() {
let foo = "";
let bar = "";
format!(); //~ ERROR requires at least a format string argument
format!(struct); //~ ERROR expected expression
format!("s", name =); //~ ERROR expected expression
format!("s", foo = foo, bar); //~ ERROR expected `=`
format!("s", foo = struct); //~ ERROR expected expression
format!(
"s {foo} {} {}",
foo = foo,
bar, //~ ERROR positional arguments cannot follow named arguments
);
format!("s {foo}", foo = struct); //~ ERROR expected expression
format!("s", struct); //~ ERROR expected expression
// This error should come after parsing errors to ensure they are non-fatal.

26
src/test/ui/macros/format-parse-errors.stderr
View file

@ -1,5 +1,5 @@
error: requires at least a format string argument
--> $DIR/format-parse-errors.rs:2:5
--> $DIR/format-parse-errors.rs:4:5
|
LL | format!();
| ^^^^^^^^^^
@ -7,37 +7,39 @@ LL | format!();
= note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
error: expected expression, found keyword `struct`
--> $DIR/format-parse-errors.rs:3:13
--> $DIR/format-parse-errors.rs:5:13
|
LL | format!(struct);
| ^^^^^^ expected expression
error: expected expression, found end of macro arguments
--> $DIR/format-parse-errors.rs:4:24
--> $DIR/format-parse-errors.rs:6:24
|
LL | format!("s", name =);
| ^ expected expression
error: expected `=`, found end of macro arguments
--> $DIR/format-parse-errors.rs:5:32
error: positional arguments cannot follow named arguments
--> $DIR/format-parse-errors.rs:10:9
|
LL | format!("s", foo = foo, bar);
| ^ expected `=`
LL | foo = foo,
| --- named argument
LL | bar,
| ^^^ positional arguments must be before named arguments
error: expected expression, found keyword `struct`
--> $DIR/format-parse-errors.rs:6:24
--> $DIR/format-parse-errors.rs:12:30
|
LL | format!("s", foo = struct);
| ^^^^^^ expected expression
LL | format!("s {foo}", foo = struct);
| ^^^^^^ expected expression
error: expected expression, found keyword `struct`
--> $DIR/format-parse-errors.rs:7:18
--> $DIR/format-parse-errors.rs:13:18
|
LL | format!("s", struct);
| ^^^^^^ expected expression
error: format argument must be a string literal
--> $DIR/format-parse-errors.rs:10:13
--> $DIR/format-parse-errors.rs:16:13
|
LL | format!(123);
| ^^^