From 88783df4bf0ba1aaeb0108bb3a0ed885e22823cf Mon Sep 17 00:00:00 2001
From: Matt Kotsenas <Matt.Kotsenas@gmail.com>
Date: Sat, 8 Mar 2025 12:34:20 -0800
Subject: [PATCH 1/3] Set default TFM for Traversal to SDK version

Fixes #602.

Defaulting to `net45` feels odd, as it means folks are taking _new_ dependencies on .NET Framework without realizing it. It can also lead to oddities like #602 where old defaults apply to newer projects.

This change allows the user to specify a particular version as before. However, otherwise `$(NETCoreAppMaximumVersion)` becomes the default version.

I think this strikes a better balance, where users that care or need a specific version continue to do so, while those that consider Traversal projects more a facility of the build system get a more modern default.
---
 src/Traversal.UnitTests/TraversalTests.cs | 9 ++++++++-
 src/Traversal/Sdk/Traversal.targets       | 5 +++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/Traversal.UnitTests/TraversalTests.cs b/src/Traversal.UnitTests/TraversalTests.cs
index 8214e4d3..2032f189 100644
--- a/src/Traversal.UnitTests/TraversalTests.cs
+++ b/src/Traversal.UnitTests/TraversalTests.cs
@@ -204,8 +204,15 @@ public void PropertiesAreSet(string target)
         [InlineData("RestoreProjectStyle", null, "PackageReference")]
         [InlineData("StopOnFirstFailure", "false", "false")]
         [InlineData("StopOnFirstFailure", null, "true")]
+#if NETFRAMEWORK || NET9_0 // These map how MSBuild.ProjectCreation chooses SDK versions given the TFM of the test
         [InlineData("TargetFramework", "net6.0", "net6.0")]
-        [InlineData("TargetFramework", null, "net45")]
+        [InlineData("TargetFramework", null, "net9.0")]
+#elif NET8_0
+        [InlineData("TargetFramework", "net6.0", "net6.0")]
+        [InlineData("TargetFramework", null, "net8.0")]
+#else
+#error "Update test data for the given target framework"
+#endif
         [InlineData("TraversalProjectNames", "custom.proj", "custom.proj")]
         [InlineData("TraversalProjectNames", null, "dirs.proj")]
         [InlineData("UsingMicrosoftTraversalSdk", null, "true")]
diff --git a/src/Traversal/Sdk/Traversal.targets b/src/Traversal/Sdk/Traversal.targets
index bd93f9ea..72a5c0f9 100644
--- a/src/Traversal/Sdk/Traversal.targets
+++ b/src/Traversal/Sdk/Traversal.targets
@@ -26,9 +26,10 @@
     <EnableDefaultItems>false</EnableDefaultItems>
 
     <!--
-      TargetFramework is required for restore and used to default to .NET Framework v4.5.  However, Traversal projects don't specify a version so it needs to be defaulted here.
+      TargetFramework is required for restore. If the user specifies a version, use that. Otherwise, use the
+      NETCoreAppMaximumVersion so that the project acts as if it were part of the SDK.
     -->
-    <TargetFramework Condition="'$(TargetFramework)' == ''">net45</TargetFramework>
+    <TargetFramework Condition=" '$(TargetFramework)' == '' ">net$(NETCoreAppMaximumVersion)</TargetFramework>
   </PropertyGroup>
 
   <Import Project="Sdk.targets" Sdk="Microsoft.NET.Sdk" />

From 1cc6311534af302ecbfc8179f92edc50e4a11574 Mon Sep 17 00:00:00 2001
From: Matt Kotsenas <matt.kotsenas@gmail.com>
Date: Mon, 10 Mar 2025 11:31:10 -0700
Subject: [PATCH 2/3] Fix TFM if max version isn't set

---
 src/Traversal/Sdk/Traversal.targets | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/Traversal/Sdk/Traversal.targets b/src/Traversal/Sdk/Traversal.targets
index 72a5c0f9..05bffcba 100644
--- a/src/Traversal/Sdk/Traversal.targets
+++ b/src/Traversal/Sdk/Traversal.targets
@@ -27,9 +27,11 @@
 
     <!--
       TargetFramework is required for restore. If the user specifies a version, use that. Otherwise, use the
-      NETCoreAppMaximumVersion so that the project acts as if it were part of the SDK.
+      NETCoreAppMaximumVersion so that the project acts as if it were part of the SDK. If for some reason that's also
+      not set, fallback to the SDK's old default of .NET Framework v4.5.
     -->
-    <TargetFramework Condition=" '$(TargetFramework)' == '' ">net$(NETCoreAppMaximumVersion)</TargetFramework>
+    <TargetFramework Condition=" '$(TargetFramework)' == '' And '$(NETCoreAppMaximumVersion)' != ''">net$(NETCoreAppMaximumVersion)</TargetFramework>
+    <TargetFramework Condition=" '$(TargetFramework)' == ''">net45</TargetFramework>
   </PropertyGroup>
 
   <Import Project="Sdk.targets" Sdk="Microsoft.NET.Sdk" />

From 77ae736c1c5be1842f86b4df7f82e247a31b751a Mon Sep 17 00:00:00 2001
From: Matt Kotsenas <matt.kotsenas@gmail.com>
Date: Mon, 10 Mar 2025 11:31:15 -0700
Subject: [PATCH 3/3] Bump version

---
 src/Traversal/version.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Traversal/version.json b/src/Traversal/version.json
index 36509201..05408c3a 100644
--- a/src/Traversal/version.json
+++ b/src/Traversal/version.json
@@ -1,4 +1,4 @@
 {
   "inherit": true,
-  "version": "4.1"
+  "version": "5.0"
 }