6.6.0

Intro:

This release adds net10.0 to the frameworks the SDK targets, next to net8.0 and
netstandard2.1. It also lets FhirClient send a resource directly as the body of an operation
request, extends the FHIRPath htmlChecks() function to string input, and makes the
SnapshotGenerator report differential elements that are out of order. There is one binary
breaking change: ElementNavFhirExtensions.HtmlChecks(PocoNode) now returns bool? instead of
bool. Code that calls it needs to be recompiled. See the FHIRPath notes below.

Platform support

• The SDK now also targets net10.0, next to net8.0 and netstandard2.1. This is additive: .NET 8
  and .NET 9 applications keep resolving to the net8.0 assets. On .NET 10, class mapping lookups
  by name through ModelInspector.FindClassMapping(ReadOnlySpan<char>) no longer allocate.
• net8.0 remains supported until the next major version (SDK 7), even after Microsoft ends support
  for .NET 8 in November 2026.
• Upcoming: netstandard2.1 will be removed in a later minor release, once Unity 6.8 - which
  replaces Mono with CoreCLR and .NET 10 - has shipped. Its only remaining audience is Unity, and
  Unity 6.8 can consume the net10.0 assets. If you depend on the netstandard2.1 assets for
  another platform, please let us know.

FhirClient

• Operations with exactly one resource input can now send that resource directly as the POST body,
  instead of wrapping it in a Parameters resource. WholeSystemOperationAsync,
  TypeOperationAsync, InstanceOperationAsync and OperationAsync have new overloads that take a
  Resource, and TransactionBuilder has matching overloads for its operation entries. The
  existing Parameters overloads are unchanged. See issue #3599.

FHIRPath

• htmlChecks() can now be invoked on a string. Its contents are validated as the content of a
  narrative div, following the current FHIRPath build (FHIR-56303).
  Invoked on anything other than xhtml or a string, it now returns empty instead of false. To
  support this, ElementNavFhirExtensions.HtmlChecks(PocoNode) returns bool? instead of bool,
  which is a binary breaking change for code that calls it directly. See issue #3604.

Snapshot generation

• The SnapshotGenerator now reports a specific issue (PROFILE_ELEMENTDEF_INVALID_ELEMENT_ORDER,
  code 10020) when a differential element is out of order, i.e. when it constrains a base element
  that precedes a base element already matched by an earlier differential element. The spec
  requires differential.element and snapshot.element to follow the order of the base
  definition. Such elements could previously not be matched and were silently treated as new
  elements, which surfaced downstream as a confusing error. The generator does not reorder the
  differential. See issue #3600.

Dependencies

• The System.Reflection.Emit.Lightweight and System.Buffers package dependencies were removed;
  both are part of every framework the SDK targets.
• Updated Microsoft.SourceLink.GitHub to 10.0.401. MSTest (4.4.1) and Verify.MSTest (33.1.5) were
  updated too, but are test-only and not part of the shipped packages.

Changes:

• #3612: VONK-10067: Add net10.0 target framework and convert to slnx
• #3614: Bump the runtime-dependencies-minor group with 1 update
• #3609: Bump the runtime-dependencies-minor group with 2 updates
• #3601: Report a clear issue for out-of-order differential elements in SnapshotGenerator
• #3602: Support resource-body operation overloads
• #3605: Support FHIRPath htmlChecks() on string input
• #3608: Bump Microsoft.SourceLink.GitHub from 10.0.400 to 10.0.401
• #3607: Bump MSTest.TestFramework and Verify.MSTest
• #3603: Release 6.5.0
• #3600: SnapshotGenerator doesn't sort out-of-order differential/snapshot elements (unlike HAPI's Java validator)

This list of changes was auto generated.