eng: enable PackageValidationBaselineVersion=0.4.0 with suppression for known breaking changes

Activates binary compatibility checking against the last published release
(v0.4.0) by uncommenting PackageValidationBaselineVersion in the project file.

The build revealed 3 existing API breaks between 0.4.0 and 0.6.0-dev — all in
compiler-internal F# witness infrastructure that is technically public but not
intended for direct user consumption:

  - TaskSeqBuilder.Bind<...> (internal CE overload)
  - TaskSeqBuilder.Bind$W<...> (F# witness-passing variant, compiler-generated)
  - TaskExtensions.TaskBuilder.For<...> (for-in-IAsyncEnumerable overload)

These suppressions are recorded in CompatibilitySuppressions.xml. All future
inadvertent API breaks will now be caught automatically during dotnet build.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

release-notes.txt

@@ -3,6 +3,7 @@ Release notes:
 
 0.6.0
     - fixes: async { for item in taskSeq do ... } no longer wraps exceptions in AggregateException, #129
+    - eng: enable PackageValidationBaselineVersion=0.4.0 to enforce binary compatibility with last published release
     - adds TaskSeq.compareWith and TaskSeq.compareWithAsync
     - adds TaskSeq.scan and TaskSeq.scanAsync, #289
     - adds TaskSeq.pairwise, #289

src/FSharp.Control.TaskSeq/CompatibilitySuppressions.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- https://learn.microsoft.com/dotnet/fundamentals/package-validation/diagnostic-ids -->
+<Suppressions xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:FSharp.Control.LowPriority.TaskSeqBuilder#Bind``5(FSharp.Control.TaskSeqBuilder,``0,Microsoft.FSharp.Core.FSharpFunc{``1,Microsoft.FSharp.Core.CompilerServices.ResumableCode{FSharp.Control.TaskSeqStateMachineData{``2},Microsoft.FSharp.Core.Unit}})</Target>
+    <Left>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Left>
+    <Right>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:FSharp.Control.LowPriority.TaskSeqBuilder#Bind$W``5(Microsoft.FSharp.Core.FSharpFunc{``0,``3},Microsoft.FSharp.Core.FSharpFunc{``3,``1},Microsoft.FSharp.Core.FSharpFunc{``3,System.Boolean},FSharp.Control.TaskSeqBuilder,``0,Microsoft.FSharp.Core.FSharpFunc{``1,Microsoft.FSharp.Core.CompilerServices.ResumableCode{FSharp.Control.TaskSeqStateMachineData{``2},Microsoft.FSharp.Core.Unit}})</Target>
+    <Left>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Left>
+    <Right>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:FSharp.Control.TaskExtensions.TaskBuilder#For``2(Microsoft.FSharp.Control.TaskBuilder,System.Collections.Generic.IAsyncEnumerable{``0},Microsoft.FSharp.Core.FSharpFunc{``0,Microsoft.FSharp.Core.CompilerServices.ResumableCode{Microsoft.FSharp.Control.TaskStateMachineData{``1},Microsoft.FSharp.Core.Unit}})</Target>
+    <Left>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Left>
+    <Right>lib/netstandard2.1/FSharp.Control.TaskSeq.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
+</Suppressions>

src/FSharp.Control.TaskSeq/FSharp.Control.TaskSeq.fsproj

@@ -28,7 +28,7 @@ Generates optimized IL code through resumable state machines, and comes with a c
     <!-- Validate package structure and (when PackageValidationBaselineVersion is set) binary compatibility -->
     <EnablePackageValidation>true</EnablePackageValidation>
     <!-- Set this to the last published version to enforce binary compatibility, e.g. 0.4.0 -->
-    <!-- <PackageValidationBaselineVersion>0.4.0</PackageValidationBaselineVersion> -->
+    <PackageValidationBaselineVersion>0.4.0</PackageValidationBaselineVersion>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">