Nested index_expression is interpreted as type_instantiation_expression in certain cases

[AislingHPE]

I came across this issue with syntax highlighting where when treesitter interprets index into a map-inside-a-map using variables, it reads it as a type instantiation.

Code demonstrating this issue

package main

func other() {
	b := "b"
	c := "c"
	a := map[string]map[string]int{"b": {}}
	// doesn't work
	a[b][c] = 10
	// works
	a["b"][c] = 10
	// works
	a[b]["c"] = 10
	// works
	a["b"]["c"] = 10
}

Highlighting (using vscode theme in neovim:

Treesitter playground output:

package_clause [0, 0] - [0, 12]
  package_identifier [0, 8] - [0, 12]
function_declaration [2, 0] - [14, 1]
  name: identifier [2, 5] - [2, 10]
  parameters: parameter_list [2, 10] - [2, 12]
  body: block [2, 13] - [14, 1]
    short_var_declaration [3, 1] - [3, 9]
      left: expression_list [3, 1] - [3, 2]
        identifier [3, 1] - [3, 2]
      right: expression_list [3, 6] - [3, 9]
        interpreted_string_literal [3, 6] - [3, 9]
    short_var_declaration [4, 1] - [4, 9]
      left: expression_list [4, 1] - [4, 2]
        identifier [4, 1] - [4, 2]
      right: expression_list [4, 6] - [4, 9]
        interpreted_string_literal [4, 6] - [4, 9]
    short_var_declaration [5, 1] - [5, 40]
      left: expression_list [5, 1] - [5, 2]
        identifier [5, 1] - [5, 2]
      right: expression_list [5, 6] - [5, 40]
        composite_literal [5, 6] - [5, 40]
          type: map_type [5, 6] - [5, 31]
            key: type_identifier [5, 10] - [5, 16]
            value: map_type [5, 17] - [5, 31]
              key: type_identifier [5, 21] - [5, 27]
              value: type_identifier [5, 28] - [5, 31]
          body: literal_value [5, 31] - [5, 40]
            keyed_element [5, 32] - [5, 39]
              key: literal_element [5, 32] - [5, 35]
                interpreted_string_literal [5, 32] - [5, 35]
              value: literal_element [5, 37] - [5, 39]
                literal_value [5, 37] - [5, 39]
    comment [6, 1] - [6, 16]
    assignment_statement [7, 1] - [7, 13]
      left: expression_list [7, 1] - [7, 8]
        type_instantiation_expression [7, 1] - [7, 8]
          type: generic_type [7, 1] - [7, 5]
            type: type_identifier [7, 1] - [7, 2]
            type_arguments: type_arguments [7, 2] - [7, 5]
              type_elem [7, 3] - [7, 4]
                type_identifier [7, 3] - [7, 4]
          type_identifier [7, 6] - [7, 7]
      right: expression_list [7, 11] - [7, 13]
        int_literal [7, 11] - [7, 13]
    comment [8, 1] - [8, 9]
    assignment_statement [9, 1] - [9, 15]
      left: expression_list [9, 1] - [9, 10]
        index_expression [9, 1] - [9, 10]
          operand: index_expression [9, 1] - [9, 7]
            operand: identifier [9, 1] - [9, 2]
            index: interpreted_string_literal [9, 3] - [9, 6]
          index: identifier [9, 8] - [9, 9]
      right: expression_list [9, 13] - [9, 15]
        int_literal [9, 13] - [9, 15]
    comment [10, 1] - [10, 9]
    assignment_statement [11, 1] - [11, 15]
      left: expression_list [11, 1] - [11, 10]
        index_expression [11, 1] - [11, 10]
          operand: index_expression [11, 1] - [11, 5]
            operand: identifier [11, 1] - [11, 2]
            index: identifier [11, 3] - [11, 4]
          index: interpreted_string_literal [11, 6] - [11, 9]
      right: expression_list [11, 13] - [11, 15]
        int_literal [11, 13] - [11, 15]
    comment [12, 1] - [12, 9]
    assignment_statement [13, 1] - [13, 17]
      left: expression_list [13, 1] - [13, 12]
        index_expression [13, 1] - [13, 12]
          operand: index_expression [13, 1] - [13, 7]
            operand: identifier [13, 1] - [13, 2]
            index: interpreted_string_literal [13, 3] - [13, 6]
          index: interpreted_string_literal [13, 8] - [13, 11]
      right: expression_list [13, 15] - [13, 17]
        int_literal [13, 15] - [13, 17]