Add best-practice analyzers for nuget packaging

.netconfig

@@ -117,3 +117,8 @@
 	sha = 43712304cdfff2c34ba01197cc2ccc0e16e7af08
 	etag = 045b9e458f11f846ae9a3979b8122c68173405fb5451083d4993f94004e60e76
 	weak
+[file "src/NuGetizer.Tasks/System/Dynamic/DynamicReflection.cs"]
+	url = https://github.com/devlooped/catbag/blob/main/System/Dynamic/DynamicReflection.cs
+	sha = 8cfabc25a6e5d58aedf59364d1d8c26e64024dd2
+	etag = 2067e8993f995b6627a93438e0d97f8a6daa59bc2b3a2b0216899525c9c43edd
+	weak

src/CodeAnalysis/CodeAnalysis.csproj

@@ -11,6 +11,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="all" Visible="false" />
     <PackageReference Include="ThisAssembly.AssemblyInfo" Version="1.2.9" PrivateAssets="all" />
+    <PackageReference Include="ThisAssembly.Strings" Version="1.2.9" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1" Pack="false" />
     <PackageReference Include="Devlooped.SponsorLink" Version="0.9.9" />
   </ItemGroup>

src/CodeAnalysis/MetadataAnalyzer.cs

@@ -0,0 +1,235 @@
+using System;
+using System.Collections.Immutable;
+using System.Diagnostics;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+using static ThisAssembly;
+using static ThisAssembly.Strings;
+
+namespace NuGetizer;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp, LanguageNames.VisualBasic, LanguageNames.FSharp)]
+class MetadataAnalyzer : DiagnosticAnalyzer
+{
+    class Descriptors
+    {
+        public static readonly DiagnosticDescriptor DefaultDescription = new(
+            Strings.DefaultDescription.ID,
+            Strings.DefaultDescription.Title,
+            Strings.DefaultDescription.Message,
+            "Design",
+            DiagnosticSeverity.Warning,
+            true,
+            description: Strings.DefaultDescription.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#description");
+
+        public static readonly DiagnosticDescriptor LongDescription = new(
+            Strings.LongDescription.ID,
+            Strings.LongDescription.Title,
+            Strings.LongDescription.Message,
+            "Design",
+            DiagnosticSeverity.Error,
+            true,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#description");
+
+        public static readonly DiagnosticDescriptor MissingIcon = new(
+            Strings.MissingIcon.ID,
+            Strings.MissingIcon.Title,
+            Strings.MissingIcon.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: Strings.MissingIcon.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#icon");
+
+        public static readonly DiagnosticDescriptor MissingReadme = new(
+            Strings.MissingReadme.ID,
+            Strings.MissingReadme.Title,
+            Strings.MissingReadme.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: Strings.MissingReadme.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/NuGet/nuget-org/package-readme-on-nuget-org");
+
+        public static readonly DiagnosticDescriptor MissingLicense = new(
+            Strings.MissingLicense.ID,
+            Strings.MissingLicense.Title,
+            Strings.MissingLicense.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: Strings.MissingLicense.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#license");
+
+        public static readonly DiagnosticDescriptor DuplicateLicense = new(
+            Strings.DuplicateLicense.ID,
+            Strings.DuplicateLicense.Title,
+            Strings.DuplicateLicense.Message,
+            "Design",
+            DiagnosticSeverity.Error,
+            true,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#license");
+
+        public static readonly DiagnosticDescriptor MissingRepositoryCommit = new(
+            RepositoryCommit.ID,
+            RepositoryCommit.Title,
+            RepositoryCommit.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: RepositoryCommit.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/dotnet/standard/library-guidance/sourcelink");
+
+        public static readonly DiagnosticDescriptor MissingRepositoryUrl = new(
+            RepositoryUrl.ID,
+            RepositoryUrl.Title,
+            RepositoryUrl.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: RepositoryUrl.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/reference/nuspec#repository");
+
+        public static readonly DiagnosticDescriptor MissingProjectUrl = new(
+            ProjectUrl.ID,
+            ProjectUrl.Title,
+            ProjectUrl.MessageString,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: ProjectUrl.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/nuget/create-packages/package-authoring-best-practices#package-metadata");
+
+        public static readonly DiagnosticDescriptor MissingSourceLink = new(
+            SourceLink.ID,
+            SourceLink.Title,
+            SourceLink.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: SourceLink.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/dotnet/standard/library-guidance/sourcelink");
+
+        public static readonly DiagnosticDescriptor MissingSourceEmbed = new(
+            SourceLinkEmbed.ID,
+            SourceLinkEmbed.Title,
+            SourceLinkEmbed.Message,
+            "Design",
+            DiagnosticSeverity.Info,
+            true,
+            description: SourceLinkEmbed.Description,
+            helpLinkUri: "https://learn.microsoft.com/en-us/dotnet/standard/library-guidance/sourcelink");
+    }
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics { get; } = ImmutableArray.Create(
+        Descriptors.DefaultDescription,
+        Descriptors.LongDescription,
+        Descriptors.MissingIcon,
+        Descriptors.MissingReadme,
+        Descriptors.MissingLicense,
+        Descriptors.DuplicateLicense,
+        Descriptors.MissingRepositoryCommit,
+        Descriptors.MissingRepositoryUrl,
+        Descriptors.MissingProjectUrl,
+        Descriptors.MissingSourceLink,
+        Descriptors.MissingSourceEmbed);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.EnableConcurrentExecution();
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+
+        context.RegisterCompilationAction(ctx =>
+        {
+            var options = ctx.Options.AnalyzerConfigOptionsProvider.GlobalOptions;
+
+            // If the project isn't packable, don't issue any warnings.
+            if (!options.TryGetValue("build_property.PackageId", out var packageId) ||
+                string.IsNullOrEmpty(packageId))
+                return;
+
+            var isPacking = options.TryGetValue("build_property.IsPacking", out var packingProp) &&
+                "true".Equals(packingProp, StringComparison.OrdinalIgnoreCase);
+
+            var sourceLinkEnabled = options.TryGetValue("build_property.EnableSourceLink", out var enableSLProp) &&
+                "true".Equals(enableSLProp, StringComparison.OrdinalIgnoreCase);
+
+            if (options.TryGetValue("build_property.Description", out var description))
+            {
+                if (description == DefaultDescription.DefaultValue)
+                    ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.DefaultDescription, null));
+                // There is really no way of getting such a long text in the diagnostic. We actually get an empty string.
+                else if (description.Length > 4000)
+                    ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.LongDescription, null));
+            }
+
+            string? packageIcon = default;
+            string? packageIconUrl = default;
+
+            if (!options.TryGetValue("build_property.PackageIcon", out packageIcon) &&
+                !options.TryGetValue("build_property.PackageIconUrl", out packageIconUrl))
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingIcon, null));
+            else if (string.IsNullOrWhiteSpace(packageIcon) && string.IsNullOrWhiteSpace(packageIconUrl))
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingIcon, null));
+
+            if (!options.TryGetValue("build_property.PackageReadmeFile", out var readme) ||
+                string.IsNullOrWhiteSpace(readme))
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingReadme, null));
+
+            string? licenseExpr = default;
+            string? licenseFile = default;
+            string? licenseUrl = default;
+
+            options.TryGetValue("build_property.PackageLicenseExpression", out licenseExpr);
+            options.TryGetValue("build_property.PackageLicenseFile", out licenseFile);
+            options.TryGetValue("build_property.PackageLicenseUrl", out licenseUrl);
+
+            var specified =
+                (!string.IsNullOrWhiteSpace(licenseExpr) ? 1 : 0) +
+                (!string.IsNullOrWhiteSpace(licenseFile) ? 1 : 0) +
+                (!string.IsNullOrWhiteSpace(licenseUrl) ? 1 : 0);
+
+            if (specified == 0)
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingLicense, null));
+
+            // if two or more of the license types are specified, report
+            if (specified > 1)
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.DuplicateLicense, null));
+
+            // Source control properties
+            if (options.TryGetValue("build_property.SourceControlInformationFeatureSupported", out var sccSupported) &&
+                "true".Equals(sccSupported, StringComparison.OrdinalIgnoreCase))
+            {
+                string? repoCommit = default;
+
+                if (!options.TryGetValue("build_property.RepositoryCommit", out repoCommit) ||
+                    string.IsNullOrWhiteSpace(repoCommit))
+                {
+                    ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingRepositoryCommit, null));
+                    repoCommit = default;
+                }
+
+                if (isPacking)
+                {
+                    if (!sourceLinkEnabled)
+                        ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingSourceLink, null));
+                    // When packing, suggest reproducible builds by embedding untrack sources
+                    else if (!options.TryGetValue("build_property.EmbedUntrackedSources", out var embedUntracked) ||
+                             !"true".Equals(embedUntracked, StringComparison.OrdinalIgnoreCase))
+                        ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingSourceEmbed, null));
+                }
+            }
+
+            if (!options.TryGetValue("build_property.RepositoryUrl", out var repoUrl) ||
+                string.IsNullOrWhiteSpace(repoUrl))
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingRepositoryUrl, null));
+
+            if (!options.TryGetValue("build_property.PackageProjectUrl", out var projectUrl) ||
+                string.IsNullOrWhiteSpace(projectUrl) ||
+                projectUrl == repoUrl)
+                ctx.ReportDiagnostic(Diagnostic.Create(Descriptors.MissingProjectUrl, null, repoUrl));
+
+        });
+    }
+}