Mazdak Farrokhzad 12c1e9a193

Rollup merge of #66134 - estebank:unknown-formatting-trait, r=nikomatsakis ...

Point at formatting descriptor string when it is invalid

When a formatting string contains an invalid descriptor, point at it
instead of the argument:

```
error: unknown format trait `foo`
  --> $DIR/ifmt-bad-arg.rs:86:17
   |
LL |     println!("{:foo}", 1);
   |                 ^^^
   |
   = note: the only appropriate formatting traits are:
           - ``, which uses the `Display` trait
           - `?`, which uses the `Debug` trait
           - `e`, which uses the `LowerExp` trait
           - `E`, which uses the `UpperExp` trait
           - `o`, which uses the `Octal` trait
           - `p`, which uses the `Pointer` trait
           - `b`, which uses the `Binary` trait
           - `x`, which uses the `LowerHex` trait
           - `X`, which uses the `UpperHex` trait
```

2019-11-09 07:18:32 +01:00

..

if-branch-types.rs

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if-branch-types.stderr

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if-let-arm-types.rs

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if-let-arm-types.stderr

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if-let.rs

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if-let.stderr

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if-loop.rs

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if-no-match-bindings.rs

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if-no-match-bindings.stderr

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if-typeck.rs

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if-typeck.stderr

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if-without-block.rs

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if-without-block.stderr

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if-without-else-as-fn-expr.rs

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if-without-else-as-fn-expr.stderr

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if-without-else-result.rs

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if-without-else-result.stderr

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ifmt-bad-arg.rs

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ifmt-bad-arg.stderr

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ifmt-bad-format-args.rs

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ifmt-bad-format-args.stderr

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ifmt-unimpl.rs

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ifmt-unimpl.stderr

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ifmt-unknown-trait.rs

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ifmt-unknown-trait.stderr

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