Fix non-greedy request header matching

[martincostello]

Fix issue where request header matching was based on the order of registrations, rather than the number of headers, which could cause a response intended for a less-specific HTTP request to be returned for a more-specific HTTP registration due to the first match winning. The ordering was also non-deterministic as the LINQ sort on the object's identity (hash code) isn't stable if all the priorities are the same.

For example, if you had an HTTP request for an unauthenticated resource with an Accept header that should return 401 and then another that returns 200 when Authorization is added, the 401 response could sometimes be selected if it appeared first in the enumerated candidates because the 401 request contains a subset of the required headers (i.e. Accept with the expected value), so it still matched.

Fixed by sorting the matches to enumerate from most-to-least count of request headers so more-specific registrations are tried before less-specific ones.

The issue can be worked around by using priorities, but this change makes the default behaviour more intuitive.

Also migrates from .sln to .slnx.

[Copilot]

Pull Request Overview

This PR ensures HTTP request header matching favors registrations with more headers (more specific) before those with fewer, fixing nondeterministic first-match behavior, and updates solution format.

• Sorts mappings by header count after priority to match more-specific requests first
• Adds a test to verify correct header-matching precedence
• Migrates from .sln to .slnx solution file

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/HttpClientInterception.Tests/Bundles/header-matching.json	New bundle defining authorized and unauthorized request scenarios
tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs	Added test Can_Intercept_Http_Requests_With_Correct_Precedence_For_Http_Request_Headers
src/HttpClientInterception/HttpClientInterceptorOptions.cs	Updated BuildResponseAsync to sort by number of request headers
HttpClientInterception.slnx	Added new .slnx solution manifest
HttpClientInterception.sln	Removed obsolete .sln file

Comments suppressed due to low confidence (1)

tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs:631

• The test currently asserts only the response body. It should also verify that the Content-Type header from the bundle is applied correctly (e.g. via firstResponse.Content.Headers.ContentType).

        first.ShouldBe("unauthorized");

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.33%. Comparing base (5e92c65) to head (755c006).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1061   +/-   ##
=======================================
  Coverage   99.32%   99.33%           
=======================================
  Files          15       15           
  Lines         886      896   +10     
  Branches      204      205    +1     
=======================================
+ Hits          880      890   +10     
  Misses          4        4           
  Partials        2        2           

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linux	99.33% <100.00%> (+<0.01%)	⬆️
macos	99.33% <100.00%> (+<0.01%)	⬆️
windows	99.33% <100.00%> (+<0.01%)	⬆️

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[slang25]

That makes sense, having more sensible defaults makes things more usable.
Thanks for the slnx migration too 🥳

[Demetrios-loutsios]

Thanks for the slnx migration too 🥳

How very Martin of you! 😅 🙇