feat: inventory #:sdk and #:package from C# file-based apps

README.md

@@ -26,6 +26,7 @@ The NuGet branch of commands have recursively from given path inventories packag
 * packages.config
 * .NET Tool manifests
 * Cake build script files
+* C# file-based apps (`*.cs` files that start with `#!/usr/bin/env dotnet`, inventorying `#:sdk` and `#:package`; omitted `#:sdk` versions are taken from `msbuild-sdks` in `global.json`)
 
 #### analyze
 

resources/src/FileBasedApp/app.cs

@@ -0,0 +1,3 @@
+#!/usr/bin/env dotnet
+#:sdk Cake.Sdk
+#:package Spectre.Console

resources/src/FileBasedApp/global.json

@@ -0,0 +1,8 @@
+{
+  "sdk": {
+    "version": "10.0.401"
+  },
+  "msbuild-sdks": {
+    "Cake.Sdk": "6.3.0"
+  }
+}

src/DPI/Commands/NuGet/NuGetAnalyzeCommand.cs

@@ -19,7 +19,7 @@ namespace DPI.Commands.NuGet
     // ReSharper disable once ClassNeverInstantiated.Global
     public class NuGetAnalyzeCommand<TSettings> : NuGetCommand<TSettings> where TSettings : NuGetAnalyzeSettings
     {
-        private const string NuGetPackagesFilePattern = "{.csproj,dotnet-tools.json,packages.config,.cake}";
+        private const string NuGetPackagesFilePattern = "{.csproj,dotnet-tools.json,packages.config,.cake,.cs}";
 
         private NuGetParsers NuGetParsers { get; }
 
@@ -141,6 +141,12 @@ NuGetAnalyzeSettings settings
                             gitFolder,
                             filePackageReference
                         ),
+                        (_, ".cs") => NuGetParsers.FileBasedAppParser.Parse(
+                            settings,
+                            filePath,
+                            gitFolder,
+                            filePackageReference
+                        ),
                         _ => AsyncEnumerable.Empty<PackageReference>()
                     })
                 {

src/DPI/Models/NuGet/GlobalJson.cs

@@ -0,0 +1,5 @@
+namespace DPI.Models.NuGet;
+
+public record GlobalJson(
+    [property: JsonPropertyName("msbuild-sdks")] Dictionary<string, string>? MsBuildSdks
+);

src/DPI/Models/NuGet/GlobalJsonSerializerContext.cs

@@ -0,0 +1,6 @@
+using System.Text.Json.Serialization;
+
+namespace DPI.Models.NuGet;
+
+[JsonSerializable(typeof(GlobalJson))]
+internal partial class GlobalJsonSerializerContext : JsonSerializerContext;

src/DPI/Models/NuGet/NuGetSourceType.cs

@@ -8,6 +8,7 @@ public enum NuGetSourceType
         PackagesConfig,
         DotNetToolsManifest,
         ProjectAssets,
-        Cake
+        Cake,
+        FileBasedApp
     }
 }

src/DPI/Parsers/NuGet/FileBasedAppParser.cs

@@ -0,0 +1,127 @@
+using System.Text.RegularExpressions;
+using Cake.Common.IO;
+using DPI.Commands.Settings.NuGet;
+using DPI.Models.NuGet;
+
+namespace DPI.Parsers.NuGet;
+
+public partial class FileBasedAppParser : INuGetPackageReferenceParser
+{
+    public NuGetSourceType SourceType { get; } = NuGetSourceType.FileBasedApp;
+
+    [GeneratedRegex(@"^#!/usr/bin/env dotnet(?:\s|$)", RegexOptions.CultureInvariant)]
+    private static partial Regex Shebang();
+
+    [GeneratedRegex(@"^#:(sdk|package)\s+([^@]+?)(?:@(.+))?$", RegexOptions.IgnoreCase | RegexOptions.CultureInvariant)]
+    private static partial Regex PackageOrSdkDirective();
+
+    public async IAsyncEnumerable<PackageReference> Parse(
+        NuGetSettings settings,
+        FilePath filePath,
+        DirectoryPath? repoRootPath,
+        PackageReference basePackageReference
+    )
+    {
+        using (settings.Logger.BeginScope(nameof(FileBasedAppParser)))
+        {
+            await using var file = settings.Context.FileSystem.GetFile(filePath).OpenRead();
+            using var reader = new StreamReader(file, Encoding.UTF8);
+
+            var firstLine = await reader.ReadLineAsync();
+            if (firstLine is null || !Shebang().IsMatch(firstLine.TrimStart()))
+            {
+                yield break;
+            }
+
+            ILookup<string, string>? msBuildSdks = null;
+            string? line;
+            while ((line = await reader.ReadLineAsync()) != null)
+            {
+                var trimmed = line.Trim();
+
+                if (trimmed.Length == 0 || trimmed.StartsWith("//", StringComparison.Ordinal))
+                {
+                    continue;
+                }
+
+                if (!trimmed.StartsWith("#:", StringComparison.Ordinal))
+                {
+                    yield break;
+                }
+
+                var match = PackageOrSdkDirective().Match(trimmed);
+                if (!match.Success)
+                {
+                    continue;
+                }
+
+                var kind = match.Groups[1].Value;
+                var packageId = match.Groups[2].Value.Trim();
+                var version = match.Groups[3].Success
+                    ? match.Groups[3].Value.Trim()
+                    : null;
+
+                if (string.IsNullOrWhiteSpace(packageId))
+                {
+                    continue;
+                }
+
+                if (string.IsNullOrWhiteSpace(version)
+                    && kind.Equals("sdk", StringComparison.OrdinalIgnoreCase))
+                {
+                    msBuildSdks ??= await TryFindMsBuildSdks(settings, filePath, repoRootPath);
+                    version = msBuildSdks[packageId].FirstOrDefault();
+                }
+
+                yield return basePackageReference with
+                {
+                    SourceType = SourceType,
+                    PackageId = packageId,
+                    Version = string.IsNullOrWhiteSpace(version) ? null : version
+                };
+            }
+        }
+    }
+
+    private static async Task<ILookup<string, string>> TryFindMsBuildSdks(
+        NuGetSettings settings,
+        FilePath filePath,
+        DirectoryPath? gitRootPath
+    )
+    {
+        var currentDirectory = settings.Context.MakeAbsolute(filePath.GetDirectory()).Collapse();
+        var stopDir = gitRootPath is { }
+            ? settings.Context.MakeAbsolute(gitRootPath.Combine("../")).Collapse()
+            : null;
+
+        for (
+            var level = byte.MaxValue
+            ; level > 0
+              && currentDirectory.FullPath != string.Empty
+              && currentDirectory.FullPath != stopDir?.FullPath
+            ; level--
+        )
+        {
+            var globalJsonPath = currentDirectory.CombineWithFilePath("global.json");
+
+            if (settings.Context.FileExists(globalJsonPath))
+            {
+                await using var globalJsonFile = settings.Context.FileSystem.GetFile(globalJsonPath).OpenRead();
+                var globalJson = await JsonSerializer.DeserializeAsync(
+                    globalJsonFile,
+                    GlobalJsonSerializerContext.Default.GlobalJson);
+
+                return (globalJson?.MsBuildSdks ?? new Dictionary<string, string>())
+                    .ToLookup(
+                        pair => pair.Key,
+                        pair => pair.Value,
+                        StringComparer.OrdinalIgnoreCase
+                    );
+            }
+
+            currentDirectory = currentDirectory.Combine("../").Collapse();
+        }
+
+        return Array.Empty<(string key, string value)>().ToLookup(pair => pair.key, pair => pair.value);
+    }
+}

src/DPI/Parsers/NuGet/NuGetParsers.cs

@@ -6,17 +6,20 @@ public class NuGetParsers
     public INuGetPackageReferenceParser DotNetToolsManifestParser { get; }
     public INuGetPackageReferenceParser PackageConfigParser { get; }
     public INuGetPackageReferenceParser CakeParser { get; }
+    public INuGetPackageReferenceParser FileBasedAppParser { get; }
 
     public NuGetParsers(
         CsProjParser csProjParser,
         DotNetToolsManifestParser dotNetToolsManifestParser,
         PackageConfigParser packageConfigParser,
-        CakeParser cakeParser
+        CakeParser cakeParser,
+        FileBasedAppParser fileBasedAppParser
     )
     {
         CsProjParser = csProjParser;
         DotNetToolsManifestParser = dotNetToolsManifestParser;
         PackageConfigParser = packageConfigParser;
         CakeParser = cakeParser;
+        FileBasedAppParser = fileBasedAppParser;
     }
 }

src/DPI/Program.cs

@@ -13,6 +13,7 @@ static partial void AddServices(IServiceCollection services)
         .AddSingleton<DotNetToolsManifestParser>()
         .AddSingleton<PackageConfigParser>()
         .AddSingleton<CakeParser>()
+        .AddSingleton<FileBasedAppParser>()
         .AddSingleton<NuGetParsers>()
         .AddSingleton<ProjectsAssetsParser>()
         .AddSingleton<IOutputConverter, JsonOutputConverter>()