Implement basic nested language detection support

.github/workflows/build.yml

@@ -61,7 +61,13 @@ jobs:
     name: Build on ${{matrix.os}} for ${{ matrix.label }}
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
+      if: ${{ github.event_name == 'pull_request' }}
+      with:
+        ref: ${{ github.event.pull_request.head.sha }}
+
+    - uses: actions/checkout@v4
+      if: ${{ github.event_name == 'push' }}
 
     # setup .NET per the repo global.json
     - name: Setup .NET

.vscode/launch.json

@@ -52,7 +52,7 @@
       "args": [
         "--debug",
         "--filter",
-        "FSAC.lsp.${input:loader}.${input:lsp-server}.${input:testName}"
+        "FSAC.lsp.${input:loader}.${input:testName}"
       ]
     }
   ],
@@ -77,21 +77,10 @@
       "default": "WorkspaceLoader",
       "type": "pickString"
     },
-
-    {
-      "id": "lsp-server",
-      "description": "The lsp serrver",
-      "options": [
-        "FSharpLspServer",
-        "AdaptiveLspServer"
-      ],
-      "default": "AdaptiveLspServer",
-      "type": "pickString"
-    },
     {
       "id": "testName",
       "description": "the name of the test as provided to `testCase`",
       "type": "promptString"
     }
   ]
-}
+}

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
     "version": "7.0.400",
-    "allowPrerelease": true
+    "rollForward": "major"
   }
 }

src/FsAutoComplete.Core/Commands.fs

@@ -83,6 +83,10 @@ type NotificationEvent =
   | Canceled of errorMessage: string
   | FileParsed of string<LocalPath>
   | TestDetected of file: string<LocalPath> * tests: TestAdapter.TestAdapterEntry<range>[]
+  | NestedLanguagesFound of
+    file: string<LocalPath> *
+    version: int *
+    nestedLanguages: NestedLanguages.NestedLanguageDocument array
 
 module Commands =
   open System.Collections.Concurrent

src/FsAutoComplete.Core/FsAutoComplete.Core.fsproj

@@ -4,6 +4,7 @@
     <TargetFrameworks Condition="'$(BuildNet7)' == 'true'">net6.0;net7.0</TargetFrameworks>
     <TargetFrameworks Condition="'$(BuildNet8)' == 'true'">net6.0;net7.0;net8.0</TargetFrameworks>
     <IsPackable>false</IsPackable>
+    <LangVersion>preview</LangVersion>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\FsAutoComplete.Logging\FsAutoComplete.Logging.fsproj" />
@@ -58,6 +59,7 @@
     <Compile Include="SignatureHelp.fs" />
     <Compile Include="InlayHints.fs" />
     <Compile Include="SymbolLocation.fs" />
+    <Compile Include="NestedLanguages.fs" />
     <Compile Include="Commands.fs" />
   </ItemGroup>
   <Import Project="..\..\.paket\Paket.Restore.targets" />