Make unused bindings an error (#18421)

Author: T-Gro

FSharpBuild.Directory.Build.props

@@ -28,7 +28,7 @@
     <ProtoOutputPath>$(ArtifactsDir)\Bootstrap</ProtoOutputPath>
     <ValueTupleImplicitPackageVersion>4.4.0</ValueTupleImplicitPackageVersion>
     <WarnOn>$(WarnOn);1182</WarnOn>
-    <WarningsAsErrors>0025;$(WarningsAsErrors)</WarningsAsErrors>
+    <WarningsAsErrors>1182;0025;$(WarningsAsErrors)</WarningsAsErrors>
     <OtherFlags>$(OtherFlags) --nowarn:3384</OtherFlags>
     <OtherFlags>$(OtherFlags) --times --nowarn:75</OtherFlags>
     <OtherFlags Condition="$(AdditionalFscCmdFlags) != ''">$(OtherFlags) $(AdditionalFscCmdFlags)</OtherFlags>

buildtools/fslex/fslex.fsproj

@@ -5,7 +5,8 @@
     <TargetFramework>$(FSharpNetCoreProductTargetFramework)</TargetFramework>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
     <RollForward Condition="'$(BUILDING_USING_DOTNET)' == 'true'">LatestMajor</RollForward>
-    <NoWarn>$(NoWarn);64;1182;1204</NoWarn>         <!--Temporary fix for sourcebuild -->
+    <NoWarn>$(NoWarn);64;1204;1182</NoWarn>         <!--Temporary fix for sourcebuild -->
+    <OtherFlags>$(OtherFlags) --warnaserror-:1182</OtherFlags>
   </PropertyGroup>
 
   <PropertyGroup>

buildtools/fsyacc/fsyacc.fsproj

@@ -5,7 +5,8 @@
     <TargetFramework>$(FSharpNetCoreProductTargetFramework)</TargetFramework>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
     <RollForward Condition="'$(BUILDING_USING_DOTNET)' == 'true'">LatestMajor</RollForward>
-    <NoWarn>$(NoWarn);64;1182;1204</NoWarn>         <!--Temporary fix for sourcebuild -->
+    <NoWarn>$(NoWarn);64;1204;1182</NoWarn>         <!--Temporary fix for sourcebuild -->
+    <OtherFlags>$(OtherFlags) --warnaserror-:1182</OtherFlags>
   </PropertyGroup>
 
   <PropertyGroup>

tests/FSharp.Compiler.Service.Tests/EditorTests.fs

@@ -9,6 +9,8 @@ open FSharp.Compiler.Symbols
 open FSharp.Compiler.Text
 open FSharp.Compiler.Tokenization
 
+#nowarn "1182" // Unused bindings when ignored parsed results etc.
+
 let stringMethods =
     [
         "Chars"; "Clone"; "CompareTo"; "Contains"; "CopyTo"; "EndsWith";

tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.Tests.fsproj

@@ -6,6 +6,7 @@
     <TargetFrameworks Condition="'$(OS)' == 'Unix' or '$(BUILDING_USING_DOTNET)' == 'true'">$(FSharpNetCoreProductTargetFramework)</TargetFrameworks>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <NoWarn>$(NoWarn);1182</NoWarn> <!-- suppress warning for unused values in FSharp.Compiler.Service.Tests tests, very often checker results are needed, but not used -->
+    <OtherFlags>$(OtherFlags) --warnaserror-:1182</OtherFlags>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
     <UnitTestType>xunit</UnitTestType>
   </PropertyGroup>

tests/FSharp.Compiler.Service.Tests/MultiProjectAnalysisTests.fs

@@ -13,6 +13,8 @@ open FSharp.Compiler.Text
 open FSharp.Compiler.Service.Tests.Common
 open TestFramework
 
+#nowarn "1182" // Unused bindings when ignored parsed results etc.
+
 let toIList (x: _ array) = x :> IList<_>
 let numProjectsForStressTest = 100
 let internal checker = FSharpChecker.Create(projectCacheSize=numProjectsForStressTest + 10, useTransparentCompiler = CompilerAssertHelpers.UseTransparentCompiler)

tests/FSharp.Core.UnitTests/FSharp.Core.UnitTests.fsproj

@@ -13,7 +13,7 @@
     <PreRelease>true</PreRelease>
     <LangVersion>preview</LangVersion>
     <NoWarn>$(NoWarn);1182</NoWarn> <!-- suppress warning for unused values in FSharp.Core tests, there are way too many of edge case scenarios tested -->
-
+    <OtherFlags>$(OtherFlags) --warnaserror-:1182</OtherFlags>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
     <UnitTestType>xunit</UnitTestType>
     <IsTestProject>true</IsTestProject>

vsintegration/src/FSharp.VS.FSI/FSharp.VS.FSI.fsproj

@@ -6,7 +6,7 @@
     <OutputType>Library</OutputType>
     <NoWarn>$(NoWarn);47;75;1182</NoWarn><!-- 1182 - unused bindings, too many of them here -->
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
-    <OtherFlags>$(OtherFlags) --subsystemversion:6.00</OtherFlags>
+    <OtherFlags>$(OtherFlags) --subsystemversion:6.00 --warnaserror-:1182</OtherFlags>
     <EnableDefaultEmbeddedResourceItems>false</EnableDefaultEmbeddedResourceItems>
   </PropertyGroup>
 

vsintegration/src/FSharp.VS.FSI/sessions.fs

@@ -41,7 +41,7 @@ type internal EventWrapper() =
 
 /// Run function application return Some (f x) or None if execution exceeds timeout (in ms).
 /// Exceptions raised by f x are caught and reported in DEBUG mode.
-let timeoutApp descr timeoutMS (f : 'a -> 'b) (arg:'a) =
+let timeoutApp _descr timeoutMS (f : 'a -> 'b) (arg:'a) =
     use ev = new EventWrapper()
     let mutable r = None
     ThreadPool.QueueUserWorkItem(fun _ ->
@@ -57,7 +57,7 @@ let timeoutApp descr timeoutMS (f : 'a -> 'b) (arg:'a) =
                                                          "fsi.exe starts the remoting server at the end of it's initialisation sequence.\n" +
                                                          "The initialisation sequence takes an observable time (e.g. 2 seconds).\n" + 
                                                          "Remoting exceptions are to be expected on interrupt/intellisense calls made before that point.\n" +
-                                                         "Context: " + descr + "\n" +
+                                                         "Context: " + _descr + "\n" +
                                                          "Exception: " + e.ToString()) |> ignore
 #endif             
                 None
@@ -285,7 +285,7 @@ let fsiStartInfo channelName sourceFile =
     procInfo
 
 
-let nonNull = function null -> false | (s:string) -> true
+let nonNull = function null -> false | (_:string) -> true
 
 /// Represents an active F# Interactive process to which Visual Studio is connected via stdin/stdout/stderr and a remoting channel
 type FsiSession(sourceFile) = 

vsintegration/tests/MockTypeProviders/DummyProviderForLanguageServiceTesting/DummyProviderForLanguageServiceTesting.fsproj

@@ -5,7 +5,7 @@
   <PropertyGroup>
     <TargetFramework>net472</TargetFramework>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
-    <OtherFlags>$(OtherFlags) --nowarn:3390 --nowarn:3218 --nowarn:1182</OtherFlags>
+    <OtherFlags>$(OtherFlags) --nowarn:3390 --nowarn:3218 --nowarn:1182 --warnaserror-:1182</OtherFlags>
   </PropertyGroup>
 
   <ItemGroup>