[michaelthyregod]

Types of Changes

Prerequisites

• I have read the CONTRIBUTING document
• My code follows the code style of this project

Contribution Type

• Bug fix (non-breaking change which fixes an issue, please reference the issue id)
• New feature (non-breaking change which adds functionality, make sure to open an associated issue first)
• Breaking change (fix or feature that would cause existing functionality to change)
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• I have added tests to cover my changes
• All new and existing tests passed

Description

diff:match throws on .NET 8 and later when AngleSharp 1.3.1 or newer is used:

System.MissingMethodException: Method not found: '!0 AngleSharp.Dom.IHtmlCollection`1.get_Item(Int32)'.

Since 1.3.1 (AngleSharp#1226) the .NET 8 build of IHtmlCollection<T> takes its indexer from IReadOnlyList<T>, so the call compiled into this netstandard2.0 library no longer exists at runtime.

• CssSelectorElementMatcher reads its single match with First() instead of the indexer, which works on every AngleSharp version. The minimum stays at 1.1.2.
• The test project runs on AngleSharp 1.10.0, so the existing CssSelectorElementMatcherTest tests cover it: without the fix 3 of them fail there. 557/557 pass on 1.10.0 and on 1.1.2.

Suggested CHANGELOG line, for whichever heading you open:

• Improved diff:match to work with AngleSharp 1.3.1 and later on .NET 8+ (#PR) @michaelthyregod

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[CLAassistant]

All committers have signed the CLA.

[michaelthyregod]

The cause is also being fixed in AngleSharp itself: AngleSharp/AngleSharp#1410 declares the indexers on every target again. This PR is still needed for AngleSharp 1.3.1 through 1.10.x, which are already released.

[michaelthyregod]

Update: AngleSharp/AngleSharp#1410 was declined (no breaking changes in core), so this PR is the fix for diff:match. I checked the rest of the library for integer indexers on IHtmlCollection, IStringList and ITokenList; this was the only one.