Resolve false positives of unnecessary_cast for non-decimal integers #5257
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JohnTitor
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clippy_lints/src/types.rs
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| return; | ||
| if let Some(num_lit) = NumericLiteral::from_lit_kind(&src, &lit.node) { | ||
| if from_nbits != 0 && to_nbits != 0 && from_nbits <= to_nbits && | ||
| num_lit.radix != Radix::Hexadecimal { |
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I think we also want to not lint this for 0o and 0b, so you could add a is_decimal() method to the NumericLiteral struct.
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For 0o and 0b, the suffixes _f32 or _f64 would not be interpreted as part of the literal value such that the cast is indeed unnecessary. Am I correct?
However, it would probably make sense to print the suggestion also in octal or binary format. I will work on that and modify the PR accordingly.
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Same behavior for 0b and 0o Playground:
warning: casting integer literal to `f32` is unnecessary
--> src/main.rs:2:13
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2 | let _ = 0b10101 as f32;
| ^^^^^^^^^^^^^^ help: try: `21_f32`
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= note: `#[warn(clippy::unnecessary_cast)]` on by default
If any other radix, than decimal is used, it is most definitely intended, so suggesting to change it to decimal+_f32 is not something we want to do. Since binary and octal float literals are not supported, we also want to bail out there.
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Ok, thanks for the additional pointers. I will include the binary and octal case.
flip1995
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@flip1995 I moved the NumericLiteral to its own module and now also handle the binary and octal cases. I needed to make some fields public such that they remain accessible. |
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Thanks a lot for the feedback, that was very helpful. |
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☔ The latest upstream changes (presumably #5246) made this pull request unmergeable. Please resolve the merge conflicts. |
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Thanks, a rebase is needed, because of #5246. After that this is good to go. |
mlegner
changed the title
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@flip1995 Rebase done. |
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Thanks! @bors r+ |
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📌 Commit 185fa0d has been approved by |
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☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test |
This PR resolves false positives of
unnecessary_castfor hexadecimal integers to floats and adds a corresponding test case.Fixes: #5220
changelog: none