Allow mulitiple edits at the same offset.

[dantleech]

Currently an Assertion error is thrown when text edits are made in the wrong order AND when multiple edits are made in the same place. Which I believe is a mistake as this works as expected until I run it in an environment with assertions turned on:

$source = '<?php';
$textEdits[] = new TextEdit(0, 0, 'Hello');
$textEdits[] = new TextEdit(0, 0, 'World');
echo TextEdit::applyEdits($textEdits, $source);

Expected:

HelloWorld<?php

Actual: Assertion error is thrown.

If assertions are disabled (zend.assertions = -1) this works as expected.

In addtion I changed the assertion to an OutOfBounds exception due to the inconsitency of the behavior of assert.

[msftclas]

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[roblourens]

Why would you expect HelloWorld and not WorldHello? I would think that Hello would be inserted at 0, then World inserted at 0. I think this is why that limitation is there in the first place - it leads to confusing situations.

[dantleech]

I don't know if its good to have the limitation or not - I suppose it can be worked around by building up all of the edits at that offset into a single edit.

I do think that an exception would be better than assert in this case (as an exception will always be thrown whereas assert is env. specific and can lead to confusion).

[roblourens]

I don't know why one check is an assert, and the other is an exception. I think it would make sense to make the assert an exception as well. #161