helix-plus/runtime/queries/_javascript/highlights.scm

; Function and method parameters
;-------------------------------

; Javascript and Typescript Treesitter grammars deviate when defining the
; tree structure for parameters, so we need to address them in each specific
; language instead of ecma.

; (p)
(formal_parameters 
  (identifier) @variable.parameter)

; (...p)
(formal_parameters
  (rest_pattern
    (identifier) @variable.parameter))

; ({ p })
(formal_parameters
  (object_pattern
    (shorthand_property_identifier_pattern) @variable.parameter))

; ({ a: p })
(formal_parameters
  (object_pattern
    (pair_pattern
      value: (identifier) @variable.parameter)))

; ([ p ])
(formal_parameters
  (array_pattern
    (identifier) @variable.parameter))

; (p = 1)
(formal_parameters
  (assignment_pattern
    left: (identifier) @variable.parameter))