Fix up broken fake build, and upgrade projects to LTS netcoreapp3.1

Author: jwosty

.config/dotnet-tools.json

@@ -3,13 +3,13 @@
   "isRoot": true,
   "tools": {
     "fake-cli": {
-      "version": "5.20.3",
+      "version": "5.22.0",
       "commands": [
         "fake"
       ]
     },
     "paket": {
-      "version": "5.257.0",
+      "version": "7.1.5",
       "commands": [
         "paket"
       ]

Examples/Examples.WinForms.Chromium/Examples.WinForms.Chromium.fsproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
-    <TargetFrameworks>netcoreapp3.0;net48</TargetFrameworks>
+    <TargetFrameworks>net5.0-Windows;net48</TargetFrameworks>
     <UseWindowsForms>true</UseWindowsForms>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <ApplicationIcon />

Examples/Examples.Wpf.Chromium/Examples.Wpf.Chromium.fsproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
-    <TargetFrameworks>netcoreapp3.0;net48</TargetFrameworks>
+    <TargetFrameworks>net5.0-Windows;net48</TargetFrameworks>
     <UseWPF>true</UseWPF>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <ApplicationIcon />

README.md

@@ -48,6 +48,27 @@ dotnet fake build -t BuildDocs
 dotnet fake biuld -t ReleaseDocs
 ```
 
+## FAKE build error: "Unsupported log file format"
+
+Sometimes, `dotnet fake build` will start failing with messages similar to:
+
+`NotSupportedException: Unsupported log file format. Latest supported version is 9, the log file has version 14.`
+
+Fix this by running:
+
+``bash
+git clean -xdf
+rm build.fsx.lock``
+
+You may also have to run:
+
+``bash
+dotnet tool uninstall fake-cli
+dotnet tool install fake-cli
+``
+
+The build should succeed again now. You can commit the changes.
+
 ## Maintainer(s)
 
 * [@jwosty](https://github.com/jwosty)

build.fsx

@@ -4,7 +4,7 @@
 
 // F# 4.7 due to https://github.com/fsharp/FAKE/issues/2001
 #r "paket:
-nuget FSharp.Core 4.7.0
+nuget FSharp.Core 6.0.4
 nuget Fake.Core.Target
 nuget Fake.DotNet.Cli
 nuget Fake.DotNet.MSBuild
@@ -129,7 +129,7 @@ Target.create "PackageDescription" (fun _ ->
 
 let doRestore msbParams = { msbParams with DoRestore = true }
 
-let getNupkgPath version projPath =
+let getNupkgPath version (projPath: string) =
     let vstr = match version with Some v -> sprintf ".%s" v | None -> ""
     let projDir = Path.GetDirectoryName projPath
     Path.Combine ([|projDir; "bin"; "Release";