Make collapsible_if recognize the let_chains feature
#14481
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clippy_lints/src/collapsible_if.rs
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| /// If `block` is a block with either one expression or a statement containing an expression, | ||
| /// return the expression. | ||
| fn expr_block<'tcx>(block: &Block<'tcx>) -> Option<&'tcx Expr<'tcx>> { | ||
| match block.stmts { | ||
| [] => block.expr, | ||
| [stmt] => { | ||
| if let StmtKind::Semi(expr) = stmt.kind { | ||
| Some(expr) | ||
| } else { | ||
| None | ||
| } | ||
| }, | ||
| _ => None, | ||
| } | ||
| } |
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Could this better be implemented with clippy_utils::peel_blocks and then just "unpack" the statement or return the expression?
Or are you intentionally only removing 1 block?
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I am intentionally removing only one block, the top-level one in the then parts, as multiple blocks would probably indicate a design choice, and ought to be flagged by another lint if this is not needed.
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Makes sense. In that case, please extend the comment to note that this is intentionally not using peel_blocks
clippy_lints/src/collapsible_if.rs
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| Self { | ||
| let_chains_enabled: tcx.features().enabled(sym::let_chains), |
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| let_chains_enabled: tcx.features().enabled(sym::let_chains), | |
| let_chains_enabled: tcx.features().let_chains(), |
I think this is the better approach. With that, the person stabilizing this feature in rustc is also forced to remove this check.
Yes, totally automated, with the addition of this additional whitespace reformatting on top at a few places where |
samueltardieu
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Until `if let` chains are stabilized, we do not collapse them together or with other `if` expressions unless the `let_chains` feature is enabled. This is the case for example in Clippy sources.
Since Clippy uses the `let_chains` feature, there are many occasions to collapse `if` and `if let` statements.
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Until
if letchains are stabilized, we do not collapse them together or with otherifexpressions unless thelet_chainsfeature is enabled. This is the case for example in Clippy sources.This was made possible by converting the
collapsible_ifto a late lint to get access to the set of enabled features. This allows this PR to supersede #14455 and no longer require an additional configuration option.The three commits are, in order:
let_chainsfeature detection and action, and testschangelog: [
collapsible_if]: recognize the rust compilerlet_chainsfeaturer? @flip1995