@callback extensions() :: [extension()] | :any

Returns a list of file type extensions for which the module is responsible.

@callback fetch(source :: Rewrite.Source.t(), key :: key()) :: value()

Fetches the value for a specific key for the given source.

If source contains the given key then its value is returned in the shape of {:ok, value}. If source doesn't contain key, :error is returned.

@callback fetch(
  source :: Rewrite.Source.t(),
  key :: key(),
  version :: Rewrite.Source.version()
) :: value()

Fetches the value for a specific key in a source for the given version.

If source contains the given key then its value is returned in the shape of {:ok, value}. If source doesn't contain key, :error is returned.

@callback from_string(string :: Rewrite.Source.content()) :: Rewrite.Source.t()

Returns a Rewrite.Source with a filetype from the given string.

@callback from_string(string :: Rewrite.Source.content(), path :: Path.t() | nil) ::
  Rewrite.Source.t()

Returns a Rewrite.Source with a filetype from the given string and path.

@callback from_string(
  strong :: Rewrite.Source.content(),
  path :: Path.t() | nil,
  options :: opts()
) ::
  Rewrite.Source.t()

Returns a Rewrite.Source with a filetype form the given, string and options.

@callback handle_update(source :: Rewrite.Source.t(), key :: key()) :: t()

This function is called when the content or path of the source is updated.

Returns a %Source{} with an updated filetype.

@callback handle_update(source :: Rewrite.Source.t(), key :: key(), value :: value()) ::
  updates()

This function is called when the source is updated by a key that is handled by the current filetype.

Returns a keyword with the keys :content and :filetype to update the source.

@callback read!(path :: Path.t()) :: Rewrite.Source.t()

Returns a Rewrite.Source with a filetype from a file.

@callback read!(path :: Path.t(), options :: opts()) :: Rewrite.Source.t()

Returns a Rewrite.Source with a filetype from a file.

@callback undo(source :: Rewrite.Source.t()) :: Rewrite.Source.t()

This function is called after an undo of the source.