feat(theming): separate highlight for function declarations

Add separate highlighting scope for function (and method) declarations
that allows styling the declarations differently from their calls.

book/src/themes.md

@@ -193,8 +193,9 @@ We use a similar set of scopes as
 - `operator` - `||`, `+=`, `>`
 
 - `function`
- - `builtin`
- - `method`
+ - `declaration` - Declaration of a function (e.g. `fn foo() { }` in Rust)
+ - `builtin` - Built-in functions (e.q. `println!` in Rust)
+ - `method` - Methods
  - `macro`
  - `special` (preprocessor in C)
 

runtime/queries/c/highlights.scm

@@ -109,13 +109,13 @@
 (char_literal) @constant.character
 
 (call_expression
- function: (identifier) @function)
+ function: (identifier) @function.declaration)
 (call_expression
  function: (field_expression
- field: (field_identifier) @function))
+ field: (field_identifier) @function.declaration))
 (call_expression (argument_list (identifier) @variable))
 (function_declarator
- declarator: [(identifier) (field_identifier)] @function)
+ declarator: [(identifier) (field_identifier)] @function.declaration)
 (parameter_declaration
  declarator: (identifier) @variable.parameter)
 (parameter_declaration

runtime/queries/ecma/highlights.scm

@@ -26,9 +26,9 @@
 (function
  name: (identifier) @function)
 (function_declaration
- name: (identifier) @function)
+ name: (identifier) @function.declaration)
 (method_definition
- name: (property_identifier) @function.method)
+ name: (property_identifier) @function.declaration)
 
 (pair
  key: (property_identifier) @function.method

runtime/queries/go/highlights.scm

@@ -10,10 +10,10 @@
 ; Function definitions
 
 (function_declaration
- name: (identifier) @function)
+ name: (identifier) @function.declaration)
 
 (method_declaration
- name: (field_identifier) @function.method)
+ name: (field_identifier) @function.declaration)
 
 ; Identifiers
 

runtime/queries/rust/highlights.scm

@@ -263,10 +263,10 @@
  ])
 
 (function_item
- name: (identifier) @function)
+ name: (identifier) @function.declaration)
 
 (function_signature_item
- name: (identifier) @function)
+ name: (identifier) @function.declaration)
 
 ; ---
 ; Macros

runtime/themes/fleetish.toml

@@ -25,10 +25,11 @@
 "keyword.control" = "yellow" # .conditional / .repeat / .import / .return / .exception
 "operator" = "light"
 "function" = "yellow"
-"function.macro" = "green"
+"function.declaration" = { fg = "lightest", modifiers = ["bold"] }
 "function.builtin" = "green"
+"function.method" = "yellow"
+"function.macro" = "green"
 "function.special" = "green"
-"function.method" = "light"
 "tag" = "green"
 "special" = "green"
 "namespace" = "light"