[Dependency scanning] Parse JSON output into Swift data structures.

Author: DougGregor

test/ScanDependencies/Inputs/ModuleDependencyGraph.swift

@@ -0,0 +1,147 @@
+//===--------------- ModuleDependencyGraph.swift --------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2019 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+import Foundation
+
+enum ModuleDependencyId: Hashable {
+  case swift(String)
+  case clang(String)
+
+  var moduleName: String {
+    switch self {
+      case .swift(let name): return name
+      case .clang(let name): return name
+    }
+  }
+}
+
+extension ModuleDependencyId: Codable {
+  enum CodingKeys: CodingKey {
+    case swift
+    case clang
+  }
+
+  init(from decoder: Decoder) throws {
+    let container = try decoder.container(keyedBy: CodingKeys.self)
+    do {
+      let moduleName =  try container.decode(String.self, forKey: .swift)
+      self = .swift(moduleName)
+    } catch {
+      let moduleName =  try container.decode(String.self, forKey: .clang)
+      self = .clang(moduleName)
+    }
+  }
+
+  func encode(to encoder: Encoder) throws {
+    var container = encoder.container(keyedBy: CodingKeys.self)
+    switch self {
+      case .swift(let moduleName):
+        try container.encode(moduleName, forKey: .swift)
+      case .clang(let moduleName):
+        try container.encode(moduleName, forKey: .clang)
+    }
+  }
+}
+
+/// Bridging header
+struct BridgingHeader: Codable {
+  var path: String
+  var sourceFiles: [String]
+  var moduleDependencies: [String]
+}
+
+/// Details specific to Swift modules.
+struct SwiftModuleDetails: Codable {
+  /// The module interface from which this module was built, if any.
+  var moduleInterfacePath: String?
+
+  /// The bridging header, if any.
+  var bridgingHeader: BridgingHeader?
+}
+
+/// Details specific to Clang modules.
+struct ClangModuleDetails: Codable {
+  /// The path to the module map used to build this module.
+  var moduleMapPath: String
+}
+
+struct ModuleDependencies: Codable {
+  /// The path for the module.
+  var modulePath: String
+
+  /// The source files used to build this module.
+  var sourceFiles: [String] = []
+
+  /// The set of direct module dependencies of this module.
+  var directDependencies: [ModuleDependencyId] = []
+
+  /// Specific details of a particular kind of module.
+  var details: Details
+
+  /// Specific details of a particular kind of module.
+  enum Details {
+    /// Swift modules may be built from a module interface, and may have
+    /// a bridging header.
+    case swift(SwiftModuleDetails)
+
+    /// Clang modules are built from a module map file.
+    case clang(ClangModuleDetails)
+  }
+}
+
+extension ModuleDependencies.Details: Codable {
+  enum CodingKeys: CodingKey {
+    case swift
+    case clang
+  }
+
+  init(from decoder: Decoder) throws {
+    let container = try decoder.container(keyedBy: CodingKeys.self)
+    do {
+      let details = try container.decode(SwiftModuleDetails.self, forKey: .swift)
+      self = .swift(details)
+    } catch {
+      let details = try container.decode(ClangModuleDetails.self, forKey: .clang)
+      self = .clang(details)
+    }
+  }
+
+  func encode(to encoder: Encoder) throws {
+    var container = encoder.container(keyedBy: CodingKeys.self)
+    switch self {
+      case .swift(let details):
+        try container.encode(details, forKey: .swift)
+      case .clang(let details):
+        try container.encode(details, forKey: .clang)
+    }
+  }
+}
+
+/// Describes the complete set of dependencies for a Swift module, including
+/// all of the Swift and C modules and source files it depends on.
+struct ModuleDependencyGraph: Codable {
+  /// The name of the main module.
+  var mainModuleName: String
+
+  /// The complete set of modules discovered
+  var modules: [ModuleDependencyId: ModuleDependencies] = [:]
+
+  /// Information about the main module.
+  var mainModule: ModuleDependencies { modules[.swift(mainModuleName)]! }
+}
+
+let fileName = CommandLine.arguments[1]
+let data = try! Data(contentsOf: URL(fileURLWithPath: fileName))
+
+let decoder = JSONDecoder()
+let moduleDependencyGraph = try! decoder.decode(
+  ModuleDependencyGraph.self, from: data)
+print(moduleDependencyGraph)

test/ScanDependencies/module_deps.swift

@@ -2,9 +2,22 @@
 // RUN: mkdir -p %t/clang-module-cache
 // RUN: %target-swift-frontend -scan-dependencies -module-cache-path %t/clang-module-cache %s -o %t/deps.json -I %S/Inputs/CHeaders -I %S/Inputs/Swift -emit-dependencies -emit-dependencies-path %t/deps.d -import-objc-header %S/Inputs/CHeaders/Bridging.h
 
+// Check the contents of the JSON output
 // RUN: %FileCheck %s < %t/deps.json
+
+// Check the make-style dependencies file
 // RUN: %FileCheck %s -check-prefix CHECK-MAKE-DEPS < %t/deps.d
 
+// Check that the JSON parses correctly into the canonical Swift data
+// structures.
+
+// RUN: %target-build-swift %S/Inputs/ModuleDependencyGraph.swift -o %t/main
+// RUN: %target-codesign %t/main
+// RUN: %target-run %t/main %t/deps.json
+
+// REQUIRES: executable_test
+// REQUIRES: objc_interop
+
 import C
 import E