const InputValue({String text: '', TextSelection selection: const TextSelection.collapsed(offset: -1), TextRange composing: TextRange.empty })

Creates configuration information for an input field

The selection and composing range must be within the text.

The text, selection, and composing arguments must not be null but each have default values.

Source 

const InputValue({
  this.text: '',
  this.selection: const TextSelection.collapsed(offset: -1),
  this.composing: TextRange.empty
});