Add API approvals to tests

.gitignore

@@ -219,3 +219,6 @@ pip-log.txt
 *.userprefs
 
 QRCoder/PortabilityAnalysis.html
+
+# Unaccepted approval files
+*.received.txt

QRCoder.sln

@@ -15,6 +15,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "QRCoderTests", "QRCoderTest
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "QRCoder.Xaml", "QRCoder.Xaml\QRCoder.Xaml.csproj", "{A7A7E073-2504-4BA2-A63B-87AC34174789}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "QRCoderApiTests", "QRCoderApiTests\QRCoderApiTests.csproj", "{5FACE5F6-53C9-4B89-91D4-162677893574}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -119,6 +121,22 @@ Global
 		{A7A7E073-2504-4BA2-A63B-87AC34174789}.Release|x64.Build.0 = Release|Any CPU
 		{A7A7E073-2504-4BA2-A63B-87AC34174789}.Release|x86.ActiveCfg = Release|Any CPU
 		{A7A7E073-2504-4BA2-A63B-87AC34174789}.Release|x86.Build.0 = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|ARM.ActiveCfg = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|ARM.Build.0 = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|x64.Build.0 = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Debug|x86.Build.0 = Debug|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|Any CPU.Build.0 = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|ARM.ActiveCfg = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|ARM.Build.0 = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|x64.ActiveCfg = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|x64.Build.0 = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|x86.ActiveCfg = Release|Any CPU
+		{5FACE5F6-53C9-4B89-91D4-162677893574}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

QRCoderApiTests/ApiApprovalTests.cs

@@ -0,0 +1,80 @@
+using PublicApiGenerator;
+using Shouldly;
+using System.Diagnostics;
+using System.Reflection;
+using System.Xml.Linq;
+using Xunit;
+
+namespace QRCoderApiTests;
+
+/// <summary>
+/// See more info about API approval tests here <see href="https://github.com/JakeGinnivan/ApiApprover"/>.
+/// </summary>
+public class ApiApprovalTests
+{
+    [Theory]
+    [InlineData(typeof(QRCoder.QRCodeData))]
+    [InlineData(typeof(QRCoder.Xaml.XamlQRCode))]
+    public void PublicApi(Type type)
+    {
+        string baseDir = AppDomain.CurrentDomain.BaseDirectory;
+        string projectName = type.Assembly.GetName().Name!;
+        string testDir = Path.Combine(baseDir, $"..{Path.DirectorySeparatorChar}..{Path.DirectorySeparatorChar}..");
+        string projectDir = Path.Combine(testDir, "..");
+        string buildDir = Path.Combine(projectDir, projectName, "bin", "Debug");
+        Debug.Assert(Directory.Exists(buildDir), $"Directory '{buildDir}' doesn't exist");
+        string csProject = Path.Combine(projectDir, projectName, projectName + ".csproj");
+        var project = XDocument.Load(csProject);
+        string[] tfms = project.Descendants("TargetFrameworks").Union(project.Descendants("TargetFramework")).First().Value.Split(";", StringSplitOptions.RemoveEmptyEntries);
+
+        // There may be old stuff from earlier builds like net45, netcoreapp3.0, etc. so filter it out
+        string[] actualTfmDirs = Directory.GetDirectories(buildDir).Where(dir => tfms.Any(tfm => dir.EndsWith(tfm))).ToArray();
+        Debug.Assert(actualTfmDirs.Length > 0, $"Directory '{buildDir}' doesn't contain subdirectories matching {string.Join(";", tfms)}");
+
+        (string tfm, string content)[] publicApi = actualTfmDirs.Select(tfmDir => (new DirectoryInfo(tfmDir).Name.Replace(".", ""), Assembly.LoadFile(Path.Combine(tfmDir, projectName + ".dll")).GeneratePublicApi(new ApiGeneratorOptions
+        {
+            IncludeAssemblyAttributes = false,
+            //AllowNamespacePrefixes = new[] { "Microsoft.Extensions.DependencyInjection" },
+            ExcludeAttributes = new[] { "System.Diagnostics.DebuggerDisplayAttribute", "System.Diagnostics.CodeAnalysis.AllowNullAttribute" }
+        }) + Environment.NewLine)).ToArray();
+
+        if (publicApi.DistinctBy(item => item.content).Count() == 1)
+        {
+            AutoApproveOrFail(publicApi[0].content, "");
+        }
+        else
+        {
+            foreach (var item in publicApi.ToLookup(item => item.content))
+            {
+                AutoApproveOrFail(item.Key, string.Join("+", item.Select(x => x.tfm).OrderBy(x => x)));
+            }
+        }
+
+        // Approval test should (re)generate approved.txt files locally if needed.
+        // Approval test should fail on CI.
+        // https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables
+        void AutoApproveOrFail(string publicApi, string folder)
+        {
+            string file = null!;
+
+            try
+            {
+                publicApi.ShouldMatchApproved(options => options.SubFolder(folder).NoDiff().WithFilenameGenerator((testMethodInfo, discriminator, fileType, fileExtension) => file = $"{type.Assembly.GetName().Name}.{fileType}.{fileExtension}"));
+            }
+            catch (ShouldMatchApprovedException) when (Environment.GetEnvironmentVariable("CI") == null)
+            {
+                string? received = Path.Combine(testDir, folder, file);
+                string? approved = received.Replace(".received.txt", ".approved.txt");
+                if (File.Exists(received) && File.Exists(approved))
+                {
+                    File.Copy(received, approved, overwrite: true);
+                    File.Delete(received);
+                }
+                else
+                {
+                    throw;
+                }
+            }
+        }
+    }
+}

QRCoderApiTests/QRCoder.Xaml.approved.txt

@@ -0,0 +1,18 @@
+namespace QRCoder.Xaml
+{
+    public class XamlQRCode : QRCoder.AbstractQRCode, System.IDisposable
+    {
+        public XamlQRCode() { }
+        public XamlQRCode(QRCoder.QRCodeData data) { }
+        public System.Windows.Media.DrawingImage GetGraphic(int pixelsPerModule) { }
+        public System.Windows.Media.DrawingImage GetGraphic(int pixelsPerModule, bool drawQuietZones) { }
+        public System.Windows.Media.DrawingImage GetGraphic(System.Windows.Size viewBox, bool drawQuietZones = true) { }
+        public System.Windows.Media.DrawingImage GetGraphic(int pixelsPerModule, string darkColorHex, string lightColorHex, bool drawQuietZones = true) { }
+        public System.Windows.Media.DrawingImage GetGraphic(System.Windows.Size viewBox, System.Windows.Media.Brush darkBrush, System.Windows.Media.Brush lightBrush, bool drawQuietZones = true) { }
+        public double GetUnitsPerModule(System.Windows.Size viewBox, bool drawQuietZones = true) { }
+    }
+    public static class XamlQRCodeHelper
+    {
+        public static System.Windows.Media.DrawingImage GetQRCode(string plainText, int pixelsPerModule, string darkColorHex, string lightColorHex, QRCoder.QRCodeGenerator.ECCLevel eccLevel, bool forceUtf8 = false, bool utf8BOM = false, QRCoder.QRCodeGenerator.EciMode eciMode = 0, int requestedVersion = -1, bool drawQuietZones = true) { }
+    }
+}

QRCoderApiTests/QRCoderApiTests.csproj

@@ -0,0 +1,23 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\QRCoder.Xaml\QRCoder.Xaml.csproj" />
+    <ProjectReference Include="..\QRCoder\QRCoder.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="PublicApiGenerator" Version="11.1.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="xunit" Version="2.4.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
+    <PackageReference Include="shouldly" Version="4.0.3" />
+  </ItemGroup>
+
+</Project>