jinja : parse unary +/- before variables (#29244)
* jinja : parse unary +/- before variables
Lexer already emits unary_operator for -n / +n, and runtime executes
unary -. Parse them at multiplicative precedence so slices like
items[:-n] and GigaChat indent[:-indent_factor] work.
* jinja : keep filters/tests outside unary operands
Unary +/- must bind only the primary/postfix operand so -n|abs is
(-n)|abs, not -(n|abs). Add unary + and filter/test regression coverage.
Signed-off-by: sinksilk <785976238@qq.com>
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Signed-off-by: sinksilk <785976238@qq.com>
