Creates a valid position. If the position is outside of the backing document, this method will return a position that is ensured to be inside the document and valid.
For example, when the position is { line: 1, character: 0 } and the document is empty, this method will return with { line: 0, character: 0 }.
Creates a valid range. If the range argument is outside of the document, this method will return with a new range that does not exceed the boundaries of the document.
For example, if the argument is { start: { line: 1, character: 0 }, end: { line: 1, character: 0 } } and the document is empty, the return value is
{ start: { line: 0, character: 0 }, end: { line: 0, character: 0 } }.
1.8.0