Add a Nix flake

.config/dotnet-tools.json

@@ -3,10 +3,16 @@
   "isRoot": true,
   "tools": {
     "fantomas": {
-      "version": "6.0.5",
+      "version": "7.0.3",
       "commands": [
         "fantomas"
       ]
+    },
+    "fsharp-analyzers": {
+      "version": "0.33.1",
+      "commands": [
+        "fsharp-analyzers"
+      ]
     }
   }
 }

.envrc

@@ -0,0 +1,23 @@
+use flake
+DOTNET_PATH=$(readlink "$(which dotnet)")
+SETTINGS_FILE=$(find . -maxdepth 1 -type f -name '*.sln.DotSettings.user')
+MSBUILD=$(realpath "$(find "$(dirname "$DOTNET_PATH")/../share/dotnet/sdk" -maxdepth 2 -type f -name MSBuild.dll)")
+if [ -f "$SETTINGS_FILE" ] ; then
+    xmlstarlet ed --inplace \
+    -N wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation" \
+    -N x="http://schemas.microsoft.com/winfx/2006/xaml" \
+    -N s="clr-namespace:System;assembly=mscorlib" \
+    -N ss="urn:shemas-jetbrains-com:settings-storage-xaml" \
+    --update "//s:String[@x:Key='/Default/Environment/Hierarchy/Build/BuildTool/DotNetCliExePath/@EntryValue']" \
+    --value "$(realpath "$(dirname "$DOTNET_PATH")/../share/dotnet/dotnet")" \
+    "$SETTINGS_FILE"
+
+    xmlstarlet ed --inplace \
+    -N wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation" \
+    -N x="http://schemas.microsoft.com/winfx/2006/xaml" \
+    -N s="clr-namespace:System;assembly=mscorlib" \
+    -N ss="urn:shemas-jetbrains-com:settings-storage-xaml" \
+    --update "//s:String[@x:Key='/Default/Environment/Hierarchy/Build/BuildTool/CustomBuildToolPath/@EntryValue']" \
+    --value "$MSBUILD" \
+    "$SETTINGS_FILE"
+fi

.github/workflows/dotnet.yaml

@@ -0,0 +1,148 @@
+# yaml-language-server: $schema=https://raw.githubusercontent.com/SchemaStore/schemastore/master/src/schemas/json/github-workflow.json
+name: .NET
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+env:
+  DOTNET_NOLOGO: true
+  DOTNET_CLI_TELEMETRY_OPTOUT: true
+  DOTNET_SKIP_FIRST_TIME_EXPERIENCE: true
+  NUGET_XMLDOC_MODE: ''
+  DOTNET_MULTILEVEL_LOOKUP: 0
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0 # so that NerdBank.GitVersioning has access to history
+    - name: Install Nix
+      uses: cachix/install-nix-action@v30
+      with:
+        extra_nix_config: |
+          access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+    - name: Restore dependencies
+      run: nix develop --command dotnet restore
+    - name: Build
+      run: nix develop --command dotnet build --no-restore --configuration Release
+    - name: Test
+      run: nix develop --command dotnet test
+
+  build-nix:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v30
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Build
+        run: nix build
+      - name: Reproducibility check
+        run: nix build --rebuild
+
+  check-dotnet-format:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v30
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Run Fantomas
+        run: nix run .#fantomas -- --check .
+
+  check-nix-format:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v30
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Run Alejandra
+        run: nix develop --command alejandra --check .
+
+  flake-check:
+    name: Check flake
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+      - name: Install Nix
+        uses: cachix/install-nix-action@v30
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Flake check
+        run: nix flake check
+
+  linkcheck:
+    name: Check links
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+      - name: Install Nix
+        uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+      - name: Run link checker
+        run: nix develop --command markdown-link-check README.md
+
+  nuget-pack:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0 # so that NerdBank.GitVersioning has access to history
+    - name: Install Nix
+      uses: cachix/install-nix-action@v31
+      with:
+        extra_nix_config: |
+          access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+    - name: Restore dependencies
+      run: nix develop --command dotnet restore
+    - name: Build
+      run: nix develop --command dotnet build --no-restore --configuration Release
+    - name: Pack
+      run: nix develop --command dotnet pack --configuration Release
+    - name: Upload NuGet artifact
+      uses: actions/upload-artifact@v4
+      with:
+        name: nuget-package
+        path: FicroKanSharp/bin/Release/FicroKanSharp.*.nupkg
+
+  expected-pack:
+    needs: [nuget-pack]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download NuGet artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: nuget-package
+          path: packed
+      - name: Check NuGet contents
+        # Verify that there is exactly one nupkg in the artifact that would be NuGet published
+        run: if [[ $(find packed -maxdepth 1 -name 'FicroKanSharp.*.nupkg' -printf c | wc -c) -ne "1" ]]; then exit 1; fi
+
+  all-required-checks-complete:
+    if: ${{ always() }}
+    needs: [check-dotnet-format, check-nix-format, build, build-nix, flake-check, nuget-pack, expected-pack]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: G-Research/common-actions/check-required-lite@2b7dc49cb14f3344fbe6019c14a31165e258c059
+        with:
+          needs-context: ${{ toJSON(needs) }}
+

.gitignore

@@ -7,3 +7,5 @@ riderModule.iml
 *.user
 *.DotSettings
 .DS_Store
+.direnv/
+result

FicroKanSharp.Test/Arithmetic.fs

@@ -2,11 +2,12 @@ namespace FicroKanSharp.Test
 
 open FicroKanSharp
 open FsUnitTyped
-open Xunit
+open NUnit.Framework
 
+[<TestFixture>]
 module Arithmetic =
 
-    [<Fact>]
+    [<Test>]
     let ``Arithmetic example, untyped`` () =
         let zero : Term = Term.Symbol ("zero", [])
 
@@ -76,7 +77,7 @@ module Arithmetic =
         | Zero
         | Succ of TypedTerm<Nat>
 
-    [<Fact>]
+    [<Test>]
     let ``Arithmetic example, typed`` () =
         let rec ofInt (n : int) : TypedTerm<Nat> =
             if n = 0 then

FicroKanSharp.Test/FicroKanSharp.Test.fsproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFramework>net6.0</TargetFramework>
+        <TargetFramework>net9.0</TargetFramework>
     </PropertyGroup>
 
     <ItemGroup>
@@ -14,10 +14,10 @@
     </ItemGroup>
 
     <ItemGroup>
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
-        <PackageReference Include="xunit" Version="2.4.1" />
-        <PackageReference Include="FsUnit" Version="4.1.0" />
-        <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
+        <PackageReference Include="NUnit" Version="4.4.0" />
+        <PackageReference Include="NUnit3TestAdapter" Version="5.2.0" />
+        <PackageReference Include="FsUnit" Version="7.1.1" />
     </ItemGroup>
 
     <ItemGroup>

FicroKanSharp.Test/Geometry.fs

@@ -4,8 +4,9 @@ namespace FicroKanSharp.Test
 
 open FsUnitTyped
 open FicroKanSharp
-open Xunit
+open NUnit.Framework
 
+[<TestFixture>]
 module Geometry =
 
     type Point<'a> = Point of TypedTerm<'a> * TypedTerm<'a>
@@ -34,7 +35,7 @@ module Geometry =
             |> TypedTerm.Goal.callFresh
         |> TypedTerm.Goal.callFresh
 
-    [<Fact>]
+    [<Test>]
     let ``Geometry example from Learn Prolog Now`` () =
         Line (
             TypedTerm.Literal (Point (TypedTerm.Literal 1, TypedTerm.Literal 1)),

FicroKanSharp.Test/Recursive.fs

@@ -1,9 +1,10 @@
 namespace FicroKanSharp.Test
 
-open Xunit
+open NUnit.Framework
 open FsUnitTyped
 open FicroKanSharp
 
+[<TestFixture>]
 module Recursive =
 
     type Entity =
@@ -13,7 +14,7 @@ module Recursive =
         | Blood of TypedTerm<Entity>
         | Name of TypedTerm<string>
 
-    [<Fact>]
+    [<Test>]
     let ``Recursive definitions, example 1`` () : unit =
         let justAte (t1 : TypedTerm<Entity>) (t2 : TypedTerm<Entity>) : Goal =
             Goal.disj
@@ -58,7 +59,7 @@ module Recursive =
 
     type Human = Human of string
 
-    [<Fact>]
+    [<Test>]
     let ``Recursive definitions, example 2`` () : unit =
         let children =
             [

FicroKanSharp.Test/TestCustomUnification.fs

@@ -2,8 +2,9 @@ namespace FicroKanSharp.Test
 
 open FicroKanSharp
 open FsUnitTyped
-open Xunit
+open NUnit.Framework
 
+[<TestFixture>]
 module TestCustomUnification =
 
     [<RequireQualifiedAccess>]
@@ -27,7 +28,7 @@ module TestCustomUnification =
             =
             Some state
 
-    [<Fact>]
+    [<Test>]
     let ``Type with custom unification`` () =
         Goal.equiv (Term.Symbol (Int.Case1, [])) (Term.Symbol (Int.Case2, []))
         |> Goal.evaluate
@@ -94,7 +95,7 @@ module TestCustomUnification =
         else
             Term.Symbol (Peano.Succ, [ toTerm (n - 1) ])
 
-    [<Fact>]
+    [<Test>]
     let ``A custom augmented Peano naturals type`` () =
         Goal.equiv (Term.Symbol (Peano.Pure 5, [])) (toTerm 5)
         |> Goal.evaluate