[vbreuss]

An IAccessControlStrategy only receives the path and the IFileSystemExtensibility, so it can only grant or deny all access to a file or directory. Tests cannot simulate the common cases in between: a file that can be read but not written, or a directory whose files can be written but not deleted.

This adds an AccessRequest that the mock passes to the strategy:

• Access is the requested FileAccess. Enumerating a directory requests FileAccess.Read.
• IsDelete is true when the file or directory is deleted, because a plain FileAccess cannot tell a delete from a write. A delete also requests FileAccess.Write.

fileSystem.WithAccessControlStrategy(
    new DefaultAccessControlStrategy((path, _, request)
        => !(path.EndsWith("readonly.txt") && request.Access.HasFlag(FileAccess.Write))));

API changes

• New abstract base class AccessControlStrategy that implements IAccessControlStrategy and adds IsAccessGranted(string, IFileSystemExtensibility, AccessRequest). A base class, rather than a second interface, can gain virtual members later without breaking derived strategies.
• New AccessRequest with an internal constructor: only the mock creates requests, so the type can gain properties later without breaking callers or piling up constructor overloads.
• DefaultAccessControlStrategy and NullAccessControlStrategy now derive from AccessControlStrategy. DefaultAccessControlStrategy gets a constructor overload for a callback that receives the AccessRequest.
• The API snapshots under Tests/Api/ are updated for every target framework.

Compatibility

• Existing IAccessControlStrategy implementations keep working: WithAccessControlStrategy wraps them, and they still receive only path and extensibility.
• The two-parameter IsAccessGranted on AccessControlStrategy requests FileAccess.ReadWrite, so calling it never grants access by accident.
• Existing DefaultAccessControlStrategy((path, extensibility) => ...) calls still compile; the lambda's parameter count selects the overload.

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[github-actions]

Test Results

     62 files       62 suites   1h 18m 0s ⏱️
 66 189 tests  62 677 ✅  3 512 💤 0 ❌
151 377 runs  136 607 ✅ 14 770 💤 0 ❌

Results for commit 58dc265.

♻️ This comment has been updated with latest results.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
95.8% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

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[github-actions]

This is addressed in release v7.2.0.