Remove unnecessary range replacements #128224
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The current code is this: ``` self.capture_state.replace_ranges.push((start_pos..end_pos, Some(target))); self.capture_state.replace_ranges.extend(inner_attr_replace_ranges); ``` What's not obvious is that every range in `inner_attr_replace_ranges` must be a strict sub-range of `start_pos..end_pos`. Which means, in `LazyAttrTokenStreamImpl::to_attr_token_stream`, they will be done first, and then the `start_pos..end_pos` replacement will just overwrite them. So they aren't needed.
Imagine you have replace ranges (2..20,X) and (5..15,Y), and these tokens: ``` a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x ``` If we replace (5..15,Y) first, then (2..20,X) we get this sequence ``` a,b,c,d,e,Y,_,_,_,_,_,_,_,_,_,p,q,r,s,t,u,v,w,x a,b,X,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,u,v,w,x ``` which is what we want. If we do it in the other order, we get this: ``` a,b,X,_,_,_,_,_,_,_,_,_,_,_,_,p,q,r,s,t,u,v,w,x a,b,X,_,_,Y,_,_,_,_,_,_,_,_,_,_,_,_,_,_,u,v,w,x ``` which is wrong. So it's true that we need the `.rev()` but the comment is wrong about why.
A fully imperative style is easier to read than a half-iterator, half-imperative style. Also, rename `inner_attr` as `attr` because it might be an outer attribute.
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…r=petrochenkov Remove unnecessary range replacements This PR removes an unnecessary range replacement in `collect_tokens_trailing_token`, and does a couple of other small cleanups. r? `@petrochenkov`
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…iaskrgr Rollup of 6 pull requests Successful merges: - rust-lang#121676 (Support ?Trait bounds in supertraits and dyn Trait under a feature gate) - rust-lang#124339 (allow overwriting the output of `rustc --version`) - rust-lang#128223 (Refactor complex conditions in `collect_tokens_trailing_token`) - rust-lang#128224 (Remove unnecessary range replacements) - rust-lang#128226 (Remove redundant option that was just encoding that a slice was empty) - rust-lang#128227 (CI: do not respect custom try jobs for unrolled perf builds) r? `@ghost` `@rustbot` modify labels: rollup
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…r=petrochenkov Remove unnecessary range replacements This PR removes an unnecessary range replacement in `collect_tokens_trailing_token`, and does a couple of other small cleanups. r? ``@petrochenkov``
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Rollup of 9 pull requests Successful merges: - rust-lang#121676 (Support ?Trait bounds in supertraits and dyn Trait under a feature gate) - rust-lang#124941 (Stabilize const `{integer}::from_str_radix` i.e. `const_int_from_str`) - rust-lang#128210 (rustdoc: change title of search results) - rust-lang#128223 (Refactor complex conditions in `collect_tokens_trailing_token`) - rust-lang#128224 (Remove unnecessary range replacements) - rust-lang#128226 (Remove redundant option that was just encoding that a slice was empty) - rust-lang#128227 (CI: do not respect custom try jobs for unrolled perf builds) - rust-lang#128229 (Improve `extern "<abi>" unsafe fn()` error message) - rust-lang#128235 (Fix `Iterator::filter` docs) r? `@ghost` `@rustbot` modify labels: rollup
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…r=petrochenkov Remove unnecessary range replacements This PR removes an unnecessary range replacement in `collect_tokens_trailing_token`, and does a couple of other small cleanups. r? ```@petrochenkov```
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Rollup of 9 pull requests Successful merges: - rust-lang#124941 (Stabilize const `{integer}::from_str_radix` i.e. `const_int_from_str`) - rust-lang#127853 (`#[naked]`: report incompatible attributes) - rust-lang#128210 (rustdoc: change title of search results) - rust-lang#128223 (Refactor complex conditions in `collect_tokens_trailing_token`) - rust-lang#128224 (Remove unnecessary range replacements) - rust-lang#128226 (Remove redundant option that was just encoding that a slice was empty) - rust-lang#128227 (CI: do not respect custom try jobs for unrolled perf builds) - rust-lang#128229 (Improve `extern "<abi>" unsafe fn()` error message) - rust-lang#128235 (Fix `Iterator::filter` docs) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 9 pull requests Successful merges: - rust-lang#124941 (Stabilize const `{integer}::from_str_radix` i.e. `const_int_from_str`) - rust-lang#128201 (Implement `Copy`/`Clone` for async closures) - rust-lang#128210 (rustdoc: change title of search results) - rust-lang#128223 (Refactor complex conditions in `collect_tokens_trailing_token`) - rust-lang#128224 (Remove unnecessary range replacements) - rust-lang#128226 (Remove redundant option that was just encoding that a slice was empty) - rust-lang#128227 (CI: do not respect custom try jobs for unrolled perf builds) - rust-lang#128229 (Improve `extern "<abi>" unsafe fn()` error message) - rust-lang#128235 (Fix `Iterator::filter` docs) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#128224 - nnethercote:fewer-replace_ranges, r=petrochenkov Remove unnecessary range replacements This PR removes an unnecessary range replacement in `collect_tokens_trailing_token`, and does a couple of other small cleanups. r? ````@petrochenkov````
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This PR removes an unnecessary range replacement in
collect_tokens_trailing_token, and does a couple of other small cleanups.r? @petrochenkov