Distinguish between pseudo-class selectors and interpolation#8
Distinguish between pseudo-class selectors and interpolation#8kensternberg-authentik wants to merge 1 commit into
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# Related Links: Addresses [Issue 7: tree-sitter parses complex declaration as pseudo-class instead of CSS custom property](tree-sitter-grammars#7). # What This commit places a guard clause around the scanner expression for detecting a pseudo-class selector colon. The guard clause ensures that the character *prior to* any `{` symbol was not the start of interpolation. I have also re-run the generate under 0.24.5, so the parser, headr files, and generated grammar have been updated to the latest & greatest version. A `tree-sitter.json` file has also been generated, and the corresponding tree-sitter clause removed from `package.json` (automatically, by tooling). # Why This declaration, which has been [added to the test cases](./test/corpus/declarations.txt). ``` div { --#{$x}--left: var(--#{$y}--right); } ``` As written, when `PSEUDO_CLASS_SELECTOR_COLON` is a valid possible symbol, the scanner clause for pseudo-class selector detection passes if a `{` is detected before encountering a `}` or `;` symbol. The expression `#{$y}` in the test case meets that criteria, the lexer result is marked incorrectly, and the parser fails to parse the declaration correctly. Adding a guard that the prior character seen was a `#` and that the `{` is not the start of a nested block identified by a pseudo-class but is, instead, part of an interpolation, fixes this issue. # Test steps 1. Run the tests under the old clause and see this failure: ``` correct / expected / unexpected 1. Interpolation on both sides of a declaration: (stylesheet (rule_set (selectors (tag_name)) (block (declaration (ERROR) (property_name (identifier) (interpolation (variable)) (identifier)) (call_expression (function_name) (arguments (identifier) (interpolation (variable)) (identifier))))))) ``` 2. Run it with the new clause and there is no more failure. :-) In fact, *all* of the tests now pass.
| "parse": "tree-sitter parse", | ||
| "test": "tree-sitter test" | ||
| }, | ||
| "tree-sitter": [ |
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Change made by tree-sitter generate version 0.24.
| while (lexer->lookahead != ';' && lexer->lookahead != '}' && !lexer->eof(lexer)) { | ||
| // We need a { to be a pseudo class selector, a ; indicates a | ||
| // property | ||
| while (lexer->lookahead != ';' && lexer->lookahead != '}' && |
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This is where the actual fix begins; here I initialize a boolean to track the prior character, record it if necessary, and ignore the problematic { if possible_interpolation is still true. I then remove the possible_interpolation if the follow-on character was not a problematic {.
Man, I hate going back and writing C again.
| @@ -0,0 +1,37 @@ | |||
| { | |||
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Added by tree-sitter generate with version 0.24.
| void tree_sitter_scss_external_scanner_reset(void *payload) {} | ||
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| unsigned tree_sitter_scss_external_scanner_serialize(void *payload, char *buffer) { return 0; } | ||
| unsigned tree_sitter_scss_external_scanner_serialize(void *payload, |
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Most of this is clang_format and whatever the original code was formatted with disagreeing. The only syntactical change is marked below.
tanberry
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Approving because I trust Ken with code and my life.
Hah! Thanks! And although this works, trying it out on the Patternfly source code revealed a whole bunch of edge cases, so I'm going to have to withdraw it and try again. It`s tree-sitter vs IBM. "Whose cuisine will reign supreme!?" |
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Related Links:
Addresses Issue 7: tree-sitter parses complex declaration as pseudo-class instead of CSS custom property.
What
This commit places a guard clause around the scanner expression for detecting a pseudo-class selector colon. The guard clause ensures that the character prior to any
{symbol was not the start of interpolation.I have also re-run the generate under 0.24.5, so the parser, headr files, and generated grammar have been updated to the latest & greatest version. A
tree-sitter.jsonfile has also been generated, and the corresponding tree-sitter clause removed frompackage.json(automatically, by tooling).Why
This declaration, which has been added to the test cases.
As written, when
PSEUDO_CLASS_SELECTOR_COLONis a valid possible symbol, the scanner clause for pseudo-class selector detection passes if a{is detected before encountering a}or;symbol. The expression#{$y}in the test case meets that criteria, the lexer result is marked incorrectly, and the parser fails to parse the declaration correctly.Adding a guard that the prior character seen was a
#and that the{is not the start of a nested block identified by a pseudo-class but is, instead, part of an interpolation, fixes this issue.Test steps