testing: Implement Macros For Cli Testing

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/Macros/Macros.swift

@@ -289,11 +289,95 @@ public struct MustOr: CodeItemMacro {
   }
 }
 
+public struct CliTestDeclarationMacro: PeerMacro, Sendable {
+
+  private static func doc_shrink(_ from: String) -> String {
+    return from.replacing(Regex(#/^.*\/\/\/[\s]+/#), with: "")
+  }
+
+  public static func expansion(
+    of node: AttributeSyntax,
+    providingPeersOf declaration: some DeclSyntaxProtocol,
+    in context: some MacroExpansionContext
+  ) throws -> [DeclSyntax] {
+
+    let cli_test_expected_output = node.leadingTrivia.filter({ $0.isComment }).map({
+      doc_shrink("\($0)")
+    }).joined(separator: "\\n")
+
+    let cli_test_driver_thunk_name = context.makeUniqueName(
+      declaration.cast(FunctionDeclSyntax.self).name.text + "_thunk_")
+    let cli_test_driver_thunk: DeclSyntax = """
+      @Sendable private func \(cli_test_driver_thunk_name)() async throws {
+        let expected = "\(raw: cli_test_expected_output)"
+
+        _ = unsafe try await Testing.__requiringUnsafe(
+          Testing.__requiringTry(
+            Testing.__requiringAwait(swiftCliTestRunner(\(declaration.cast(FunctionDeclSyntax.self).name), expected))))
+      }
+      """
+
+    let cli_test_driver_generator_name = context.makeUniqueName(
+      declaration.cast(FunctionDeclSyntax.self).name.text + "_generator_")
+    let cli_test_driver_generator: DeclSyntax = """
+        @Sendable private func \(cli_test_driver_generator_name)() async -> Testing.Test {
+          return .__function(
+            named: "xxxxxxxx()",
+            in: nil,
+            xcTestCompatibleSelector: Testing.__xcTestCompatibleSelector("xxxxxx:"),
+            traits: [],
+            sourceLocation: Testing.SourceLocation(
+              fileID: "Tests/CliTests/Cli.swift",
+              filePath: "/Users/hawkinsw/code/p4ce/Tests/p4rseTests/CliTests/Cli.swift", line: 359,
+              column: 2),
+            parameters: [],
+            testFunction: \(cli_test_driver_thunk_name)
+          )
+        }
+      """
+
+    let cli_test_driver_accessor_name = context.makeUniqueName(
+      declaration.cast(FunctionDeclSyntax.self).name.text + "_accessor_")
+    let cli_test_driver_accessor: DeclSyntax = """
+        private nonisolated let \(cli_test_driver_accessor_name): Accessor = { outValue, type, _, _ in
+
+          Testing.Test.__store(\(cli_test_driver_generator_name), into: outValue, asTypeAt: type)
+        }
+      """
+
+    let cli_test_driver_content_record_name = context.makeUniqueName(
+      declaration.cast(FunctionDeclSyntax.self).name.text + "_cr_")
+    let cli_test_driver_cr: DeclSyntax = """
+        private nonisolated let \(cli_test_driver_content_record_name): TestContentRecord = (
+          0x7465_7374, /* indicate a test */
+          0,
+          unsafe \(cli_test_driver_accessor_name),
+          0,
+          0
+        )
+      """
+
+    let cli_test_driver_content_container_name = context.makeUniqueName(
+      declaration.cast(FunctionDeclSyntax.self).name.text + "__🟡$_container_")
+    let cli_test_driver_container: DeclSyntax = """
+        struct \(cli_test_driver_content_container_name): Testing.__TestContentRecordContainer {
+          nonisolated static var __testContentRecord: TestContentRecord {
+            unsafe \(cli_test_driver_content_record_name)
+          }
+        }
+      """
+    return [
+      cli_test_driver_thunk, cli_test_driver_generator, cli_test_driver_accessor,
+      cli_test_driver_cr, cli_test_driver_container,
+    ]
+  }
+}
+
 @main
 struct P4Macros: CompilerPlugin {
   var providingMacros: [Macro.Type] = [
     RequireResult.self, RequireErrorResult.self, UseOkResult.self, UseErrorResult.self,
     RequireNodeType.self, SkipUnlessNodeType.self, SkipUnlessNodesTypes.self, RequireNodesType.self,
-    MustOr.self,
+    MustOr.self, CliTestDeclarationMacro.self,
   ]
 }