Add calc()/min()/max()/clamp()#213
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calc(), min(), max() and clamp() (CSS Values 4 10) were rejected everywhere. Add a recursive-descent CalcParser, a CalcTypeChecker implementing the type-checking rules, and a CalcValueConverter composed onto the length, line-width, angle, number, length-or-percent and angle-or-number converters so support cascades to every property built on them. The authored text is preserved. Type-checking rejects dimensionally-inconsistent expressions (calc(1px + 1s), calc(10px * 20px)), division by a constant zero, and malformed input (missing whitespace around +/-, wrong clamp() arity, empty). An angle/number expression validates in the corresponding context. Includes the nested-parentheses lexer fix (also submitted standalone), needed so a parenthesized group inside the arguments - calc((100% - 20px) / 3) - isn't cut off at the inner ')'. If that merges first, this rebases cleanly.
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Feature
calc(),min(),max()andclamp()(CSS Values 4 §10) were rejected everywhere:Implementation
CalcParser— a recursive-descent parser for the<calc-sum>/<calc-product>/<calc-value>grammar, including nestedmin/max/clampand parenthesized groups. Binary+/-require whitespace on both sides;*//don't.CalcTypeChecker— the §10.10 type-checking rules: resolves each expression to aCalcCategory(number/length/percentage/angle/…) or rejects a dimensionally-inconsistent one. It folds pure-number subtrees so a constant divide-by-zero is caught here.CalcValueConverter— accepts a calc expression whose category fits the context, and preserves the authored text. Composed onto the length, line-width, angle, number, length-or-percent, and angle-or-number converters, so support cascades to every property built on them.Type-checking rejects
calc(1px + 1s),calc(10px * 20px),calc(100% / 0),calc(1px +1px)(missing space),calc(5)in a length context,clamp(1px, 2px)(wrong arity), and empty/malformed input.The evaluation of a calc() against layout context (
em/%→ pixels) is out of scope for a parser — only parsing, type-checking and serialization are provided.Dependency
A parenthesized group inside the arguments —
calc((100% - 20px) / 3)— needs the nested-parentheses lexer fix ("Fix function tokens terminating at a nested closing parenthesis", #190). This branch includes that one change so it's self-contained; if #190 merges first, it rebases cleanly.Tests
19 cases in
PropertyTests/CalcPropertyTests.cs: calc/min/max/clamp/nesting in a length context, angle-context calc, text preservation, and eight type-check/grammar rejections.The full suite (1263 existing tests) stays green — wiring calc into the core numeric converters disturbs nothing — and all seven target frameworks build with no new warnings.