2e412fef75
Lexing precedes parsing, as you'd expect: `Lexer` creates a
`TokenStream` and `Parser` then parses that `TokenStream`.
But, in a horrendous violation of layering abstractions and common
sense, `Lexer` depends on `Parser`! The `Lexer::unclosed_delim_err`
method does some error recovery that relies on creating a `Parser` to do
some post-processing of the `TokenStream` that the `Lexer` just created.
This commit just removes `unclosed_delim_err`. This change removes
`Lexer`'s dependency on `Parser`, and also means that `lex_token_tree`'s
return value can have a more typical form.
The cost is slightly worse error messages in two obscure cases, as shown
in these tests:
- tests/ui/parser/brace-in-let-chain.rs: there is slightly less
explanation in this case involving an extra `{`.
- tests/ui/parser/diff-markers/unclosed-delims{,-in-macro}.rs: the diff
marker detection is no longer supported (because that detection is
implemented in the parser).
In my opinion this cost is outweighed by the magnitude of the code
cleanup.
31 lines
757 B
Text
31 lines
757 B
Text
error: this file contains an unclosed delimiter
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--> $DIR/brace-in-let-chain.rs:58:54
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LL | fn main() {
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| - unclosed delimiter
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...
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LL | fn quux() {
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| - unclosed delimiter
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...
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LL | fn foobar() {
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| - unclosed delimiter
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...
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LL | fn fubar() {
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| - unclosed delimiter
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...
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LL | fn qux() {
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| - unclosed delimiter
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...
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LL | fn foo() {
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| - another 3 unclosed delimiters begin from here
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...
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LL | {
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| - this delimiter might not be properly closed...
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LL | && let () = ()
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LL | }
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| - ...as it matches this but it has different indentation
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LL | }
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| ^
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error: aborting due to 1 previous error
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