Migrate ILSpy.sln to the SLNX solution format

.editorconfig

@@ -10,7 +10,7 @@ guidelines = 110
 tab_width = 4
 end_of_line = crlf
 
-# .net tooling writes the BOM to resx files on running dotnet build ILSpy.sln regardless,
+# .net tooling writes the BOM to resx files on running dotnet build ILSpy.slnx regardless,
 # so we should direct text editors to NOT change the file
 [*.resx]
 charset = utf-8-bom

.github/workflows/build-ilspy.yml

@@ -83,19 +83,19 @@ jobs:
 
     - name: Restore the application
       run: >
-        dotnet restore ILSpy.sln
+        dotnet restore ILSpy.slnx
         /p:RestoreEnablePackagePruning=false
         /p:Configuration=${{ matrix.configuration }}
         /p:Platform="$env:BuildPlatform"
 
     - name: Build
       run: >
-        dotnet build -mt ILSpy.sln --no-restore
+        dotnet build -mt ILSpy.slnx --no-restore
         -c ${{ matrix.configuration }}
         /p:Platform="$env:BuildPlatform"
 
     - name: Format check
-      run: dotnet-format whitespace --verify-no-changes --verbosity detailed ILSpy.sln
+      run: dotnet-format whitespace --verify-no-changes --verbosity detailed ILSpy.slnx
 
     - name: Execute unit tests
       id: unit-tests
@@ -107,7 +107,7 @@ jobs:
       env:
         DOTNET_gcServer: 0
       run: >
-        dotnet test --solution ilspy.sln
+        dotnet test --solution ILSpy.slnx
         --configuration ${{ matrix.configuration }}
         --no-build --report-trx
         --results-directory test-results/${{ matrix.configuration }}

.vscode/settings.json

@@ -3,8 +3,8 @@
     "files.exclude": {
         "ILSpy-tests/**": true
     },
-    "dotnet.defaultSolution": "ILSpy.sln",
+    "dotnet.defaultSolution": "ILSpy.slnx",
     "dotrush.roslyn.projectOrSolutionFiles": [
-        "ILSpy.sln"
+        "ILSpy.slnx"
     ],
 }

AGENTS.md

@@ -45,7 +45,7 @@ Windows-only frontends, packaging, and tests:
 - `ILSpy.Installer/` — WiX installer (`net472`)
 - `ILSpy.BamlDecompiler.Tests/` — BAML-decompiler tests, still WPF/Windows-bound (`net11.0-windows`)
 
-Solutions & filters: `ILSpy.sln` builds everything; `ILSpy.XPlat.slnf` is the decompiler libs + `ilspycmd` + their tests (no UI — the Linux CI target); `ILSpy.Desktop.slnf` is the UI plus its dependencies and tests; `ILSpy.Installer.sln` covers the legacy packaging, and `ILSpy.VSExtensions.slnx` the VS 2022 extension (`dotnet build`-able).
+Solutions & filters: `ILSpy.slnx` builds everything; `ILSpy.XPlat.slnf` is the decompiler libs + `ilspycmd` + their tests (no UI — the Linux CI target); `ILSpy.Desktop.slnf` is the UI plus its dependencies and tests; `ILSpy.Installer.sln` covers the legacy packaging, and `ILSpy.VSExtensions.slnx` the VS 2022 extension (`dotnet build`-able).
 
 ## ILSpy-tests submodule
 
@@ -67,14 +67,14 @@ Solutions & filters: `ILSpy.sln` builds everything; `ILSpy.XPlat.slnf` is the de
 
 ## Build / restore
 
-- **Use the repo-root pwsh scripts for these tasks, not raw `dotnet` commands** -- they carry the flags that keep the repo consistent and all target `ILSpy.sln` (extra args are forwarded):
+- **Use the repo-root pwsh scripts for these tasks, not raw `dotnet` commands** -- they carry the flags that keep the repo consistent and all target `ILSpy.slnx` (extra args are forwarded):
   - **restore** -> `restore.ps1`
   - **build** -> `build.ps1` (`-Configuration Debug|Release`)
   - **update deps / regenerate lock files** -> `updatedeps.ps1`
   - **format** -> `BuildTools/format.ps1`
   - **clean** -> `clean.ps1`; **publish** -> `publish.ps1`
 - **Why this matters:** `restore.ps1` and `updatedeps.ps1` pass `-p:RestoreEnablePackagePruning=false`, so they keep every `packages.lock.json` whole. A bare `dotnet restore`/`dotnet build` (which restores implicitly) **prunes** the lock files -- silently stripping the transitive/all-RID/DiaSymReader entries the repo deliberately carries -- and surfaces as a spurious `packages.lock.json` diff. Restore with `restore.ps1`, then build with `build.ps1 --no-restore`; if a bare build ever leaves a pruned `packages.lock.json` modified, discard it (`git checkout -- <path>`).
-- **Every project generates a `packages.lock.json`** (`RestorePackagesWithLockFile` is set in the root `Directory.Build.props`); CI NuGet caching keys off these. After adding or bumping a `PackageReference`/`PackageVersion`, regenerate the lock files with `updatedeps.ps1` (i.e. `dotnet restore ILSpy.sln --force-evaluate -p:RestoreEnablePackagePruning=false`) and commit them. The core libraries additionally set `RestoreLockedMode`, so a plain restore there fails until the lock file is refreshed.
+- **Every project generates a `packages.lock.json`** (`RestorePackagesWithLockFile` is set in the root `Directory.Build.props`); CI NuGet caching keys off these. After adding or bumping a `PackageReference`/`PackageVersion`, regenerate the lock files with `updatedeps.ps1` (i.e. `dotnet restore ILSpy.slnx --force-evaluate -p:RestoreEnablePackagePruning=false`) and commit them. The core libraries additionally set `RestoreLockedMode`, so a plain restore there fails until the lock file is refreshed.
 - The pre-commit hook runs `dotnet format` on the **whole solution** -- it IS the formatter. **Always let the hook run; never commit `.cs` with `--no-verify`.** Bypassing it lands unformatted code and forces history-wide reformat rebases later. `--no-verify` is acceptable only for commits that touch no `.cs` (e.g. `.yml`/`.md`-only).
 - **Line endings are a Windows-only concern.** The repo is `* text=auto`, so blobs are stored LF and git renormalizes on commit. On **Windows**, save new files CRLF so the hook's `git add -u` doesn't churn EOLs. On **Linux/macOS**, leave new files LF and do **not** `unix2dos` -- forcing CRLF there makes the whole working tree show as phantom-modified in `git status` (and is normalized back to LF on commit anyway).
 - **Partial commits need stash-and-pop.** The format hook only auto-formats when the staged set equals the working tree. Stash unstaged remainder before committing a subset.
@@ -100,7 +100,7 @@ Never put more than one C# language feature on one branch.
 
 ## Test discipline
 
-- Always run the test suite with `--report-trx` so failures survive: `dotnet test --solution ILSpy.sln --report-trx` (the repo pins Microsoft.Testing.Platform in `global.json`; the bare `dotnet test <sln>` form is the old VSTest syntax). Don't dismiss failures as flaky without first reproducing in isolation, then running repeatedly.
+- Always run the test suite with `--report-trx` so failures survive: `dotnet test --solution ILSpy.slnx --report-trx` (the repo pins Microsoft.Testing.Platform in `global.json`; the bare `dotnet test <sln>` form is the old VSTest syntax). Don't dismiss failures as flaky without first reproducing in isolation, then running repeatedly.
 - **`ILSpy.Tests` is serial by design** (one headless Avalonia session and one process-wide app composition per test host), so it cannot use more than one core in-process. The local optimization is **sharding across processes**: `./runuitests.ps1` runs the built Debug suite as 4 concurrent `dotnet test` hosts with disjoint filters (about 2.5x faster than one host); CI runs the same script with 2 shards on Linux/macOS. For one fixture use `dotnet test --project ILSpy.Tests/ILSpy.Tests.csproj --no-build --filter "FullyQualifiedName~MyFixture"` (the `--treenode-filter` / `--filter-class` forms are rejected by the NUnit bridge).
 - The decompiler test suite (test kinds, fixture structure, how to write tests, the compiler-matrix model) is documented in [ICSharpCode.Decompiler.Tests/AGENTS.md](ICSharpCode.Decompiler.Tests/AGENTS.md).
 - After matcher / rewriter edits, **run the relevant tests, not just the build.** `dotnet build` green ≠ behaviour correct.

BuildTools/bom-strip.ps1

@@ -29,7 +29,7 @@ $Dotfiles = @(
 $AllowedExts = @(
 	'.bat','.config','.cs','.csproj','.css','.filelist','.fs','.html','.il',
 	'.ipynb','.js','.json','.less','.manifest','.md','.projitems','.props',
-	'.ps1','.psd1','.shproj','.sln','.slnf','.svg','.template',
+	'.ps1','.psd1','.shproj','.sln','.slnf','.slnx','.svg','.template',
 	'.tt', '.txt','.vb','.vsct','.vsixlangpack','.wxl','.xaml','.xml','.xshd','.yml'
 )
 

BuildTools/pre-commit

@@ -36,11 +36,11 @@ DOTNET_FORMAT="$DOTNET_PATH/dotnet-format$EXE_SUFFIX"
 "$DOTNET_FORMAT" --version
 if [ "${1:-}" = "--format" ]; then
 	# called via format.bat
-	"$DOTNET_FORMAT" whitespace --no-restore --verbosity normal ILSpy.sln
+	"$DOTNET_FORMAT" whitespace --no-restore --verbosity normal ILSpy.slnx
 elif git diff --quiet --ignore-submodules; then
-	"$DOTNET_FORMAT" whitespace --no-restore --verbosity normal ILSpy.sln
+	"$DOTNET_FORMAT" whitespace --no-restore --verbosity normal ILSpy.slnx
 	git add -u -- \*\*.cs
 else
 	echo Partial commit: only verifying formatting
-	exec "$DOTNET_FORMAT" whitespace --verify-no-changes --no-restore --verbosity normal ILSpy.sln
+	exec "$DOTNET_FORMAT" whitespace --verify-no-changes --no-restore --verbosity normal ILSpy.slnx
 fi

BuildTools/update-assemblyinfo.ps1

@@ -115,7 +115,7 @@ try {
 		return 0;
 	}
 
-	if (-not (Test-File "ILSpy.sln")) {
+	if (-not (Test-File "ILSpy.slnx")) {
 		Write-Error "Working directory must be the ILSpy repo root!";
 		return 2;
 	}

ICSharpCode.Decompiler.Tests/AGENTS.md

@@ -114,7 +114,7 @@ produced for that compiler's IL. This beats hand-running csc versions.
 ## Running
 
 ```
-dotnet test --solution ILSpy.sln --report-trx --filter FullyQualifiedName~PrettyTestRunner.SwitchExpressions
+dotnet test --solution ILSpy.slnx --report-trx --filter FullyQualifiedName~PrettyTestRunner.SwitchExpressions
 ```
 
 (Microsoft.Testing.Platform syntax; see root `AGENTS.md` "Test discipline".) A failing

ICSharpCode.Decompiler/CSharp/Syntax/README.md

@@ -171,7 +171,7 @@ A few things that are easy to get wrong when editing the generator or the nodes
   reference the expected symbol (e.g. `Slots.Foo`) in code and let the build fail or pass.
 - **Validate with the DEBUG test run.** `CheckInvariant` is `[Conditional("DEBUG")]` and the test host
   runs DEBUG, so after any AST or transform change run the Pretty suite in DEBUG:
-  `OPENSSL_ENABLE_SHA1_SIGNATURES=1 dotnet test --solution ILSpy.sln --report-trx --no-build -c Debug
+  `OPENSSL_ENABLE_SHA1_SIGNATURES=1 dotnet test --solution ILSpy.slnx --report-trx --no-build -c Debug
   --filter "FullyQualifiedName~PrettyTestRunner"`. It checks the output is byte-identical **and**
   exercises `CheckInvariant` across every node shape -- a green run is the real signal, not a green
   build.

ILSpy.BamlDecompiler.Tests.Windows/ILSpy.BamlDecompiler.Tests.Windows.csproj

@@ -8,7 +8,7 @@
 
   <PropertyGroup>
     <!-- The BAML round-trip cases compile WPF XAML into this assembly, so the project is
-         Windows-bound (built and run only in the Windows CI leg via ILSpy.sln). EnableWindowsTargeting
+         Windows-bound (built and run only in the Windows CI leg via ILSpy.slnx). EnableWindowsTargeting
          lets the package graph restore on non-Windows hosts, so the lock file can be generated and
          verified anywhere even though the tests themselves only execute on Windows. -->
     <TargetFramework>net11.0-windows</TargetFramework>

ILSpy.Desktop.slnf

@@ -1,6 +1,6 @@
 {
 	"solution": {
-		"path": "ILSpy.sln",
+		"path": "ILSpy.slnx",
 		"projects": [
 			"ICSharpCode.BamlDecompiler\\ICSharpCode.BamlDecompiler.csproj",
 			"ICSharpCode.Decompiler.TestRunner\\ICSharpCode.Decompiler.TestRunner.csproj",

ILSpy.Tests.Windows/ILSpy.Tests.Windows.csproj

@@ -4,7 +4,7 @@
     <!-- Windows-targeted TFM unlocks Microsoft.DiaSymReader (native COM) + System.Windows
          registry APIs without conditional package gates. EnableWindowsTargeting lets the
          build satisfy the -windows reference assemblies on non-Windows OSes via the
-         cross-targeting pack, so `dotnet build ILSpy.sln` succeeds on Linux/macOS; the
+         cross-targeting pack, so `dotnet build ILSpy.slnx` succeeds on Linux/macOS; the
          tests still only execute on Windows because the binaries P/Invoke into Win32. -->
     <TargetFramework>net11.0-windows</TargetFramework>
     <EnableWindowsTargeting>true</EnableWindowsTargeting>

ILSpy.XPlat.slnf

@@ -1,6 +1,6 @@
 {
 	"solution": {
-		"path": "ILSpy.sln",
+		"path": "ILSpy.slnx",
 		"projects": [
 			"ICSharpCode.ILSpyCmd\\ICSharpCode.ILSpyCmd.csproj",
 			"ICSharpCode.ILSpyCmd.Tests\\ICSharpCode.ILSpyCmd.Tests.csproj",