Add support for reading fine-grained source file dependency graphs

Sources/SwiftDriver/CMakeLists.txt

@@ -22,6 +22,7 @@ add_library(SwiftDriver
   "Incremental Compilation/IncrementalCompilation.swift"
   "Incremental Compilation/InputIInfoMap.swift"
   "Incremental Compilation/InputInfo.swift"
+  "Incremental Compilation/SourceFileDependencyGraph.swift"
 
   Jobs/AutolinkExtractJob.swift
   Jobs/CommandLineArguments.swift

Sources/SwiftDriver/Incremental Compilation/SourceFileDependencyGraph.swift

@@ -0,0 +1,113 @@
+//===------- SourceFileDependencyGraph.swift - Read swiftdeps files -------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2020 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
+//
+//===----------------------------------------------------------------------===//
+@_implementationOnly import Yams
+
+public struct SourceFileDependencyGraph: Codable {
+  public static let sourceFileProvidesInterfaceSequenceNumber: Int = 0
+  public static let sourceFileProvidesImplementationSequenceNumber: Int = 1
+
+  private var allNodes: [Node]
+
+  public var sourceFileNodePair: (interface: Node, implementation: Node) {
+    (interface: allNodes[SourceFileDependencyGraph.sourceFileProvidesInterfaceSequenceNumber],
+     implementation: allNodes[SourceFileDependencyGraph.sourceFileProvidesImplementationSequenceNumber])
+  }
+
+  public func forEachNode(_ doIt: (Node)->Void) {
+    allNodes.forEach(doIt)
+  }
+
+  public func forEachDefDependedUpon(by node: Node, _ doIt: (Node)->Void) {
+    for sequenceNumber in node.defsIDependUpon {
+      doIt(allNodes[sequenceNumber])
+    }
+  }
+
+  public func forEachArc(_ doIt: (Node, Node)->Void) {
+    forEachNode { useNode in
+      forEachDefDependedUpon(by: useNode) { defNode in
+        doIt(defNode, useNode)
+      }
+    }
+  }
+
+  @discardableResult public func verify() -> Bool {
+    assert(Array(allNodes.indices) == allNodes.map { $0.sequenceNumber })
+    forEachNode {
+      $0.verify()
+    }
+    return true
+  }
+
+  public init(contents: String) throws {
+    let decoder = YAMLDecoder()
+    self = try decoder.decode(Self.self, from: contents)
+    assert(verify())
+  }
+}
+
+public enum DeclAspect: String, Codable {
+  case interface, implementation
+}
+
+public struct DependencyKey: Codable {
+  public enum Kind: String, Codable {
+    case topLevel
+    case nominal
+    case potentialMember
+    case member
+    case dynamicLookup
+    case externalDepend
+    case sourceFileProvide
+  }
+
+  public var kind: Kind
+  public var aspect: DeclAspect
+  public var context: String
+  public var name: String
+
+  public func verify() {
+    assert(kind != .externalDepend || aspect == .interface, "All external dependencies must be interfaces.")
+    switch kind {
+    case .topLevel, .dynamicLookup, .externalDepend, .sourceFileProvide:
+      assert(context.isEmpty && !name.isEmpty, "Must only have a name")
+    case .nominal, .potentialMember:
+      assert(!context.isEmpty && name.isEmpty, "Must only have a context")
+    case .member:
+      assert(!context.isEmpty && !name.isEmpty, "Must have both")
+    }
+  }
+}
+
+
+extension SourceFileDependencyGraph {
+  public struct Node: Codable {
+    public var key: DependencyKey
+    public var fingerprint: String?
+    public var sequenceNumber: Int
+    public var defsIDependUpon: [Int]
+    public var isProvides: Bool
+
+    public func verify() {
+      key.verify()
+
+      if key.kind == .sourceFileProvide {
+        switch key.aspect {
+        case .interface:
+          assert(sequenceNumber == SourceFileDependencyGraph.sourceFileProvidesInterfaceSequenceNumber)
+        case .implementation:
+          assert(sequenceNumber == SourceFileDependencyGraph.sourceFileProvidesImplementationSequenceNumber)
+        }
+      }
+    }
+  }
+}

Tests/SwiftDriverTests/IncrementalCompilationTests.swift

@@ -15,21 +15,7 @@ import SwiftDriver
 
 final class IncrementalCompilationTests: XCTestCase {
   func testInputInfoMapReading() throws {
-     let contents = """
-    version: "Apple Swift version 5.1 (swiftlang-1100.0.270.13 clang-1100.0.33.7)"
-    options: "abbbfbcaf36b93e58efaadd8271ff142"
-    build_time: [1570318779, 32358000]
-    inputs:
-      "/Volumes/AS/repos/swift-driver/sandbox/sandbox/sandbox/file2.swift": !dirty [1570318778, 0]
-      "/Volumes/AS/repos/swift-driver/sandbox/sandbox/sandbox/main.swift": [1570083660, 0]
-      "/Volumes/gazorp.swift": !private [0,0]
-"""
-
-    let inputInfoMap = try! InputInfoMap(contents: contents)
-    //    print(inputInfoMap.buildTime)
-    //    inputInfoMap.inputs.forEach {
-    //    print($0.key, $0.value)
-    //    }
+    let inputInfoMap = try! InputInfoMap(contents: Inputs.inputInfoMap)
     XCTAssertEqual(inputInfoMap.swiftVersion,
       "Apple Swift version 5.1 (swiftlang-1100.0.270.13 clang-1100.0.33.7)")
     XCTAssertEqual(inputInfoMap.argsHash, "abbbfbcaf36b93e58efaadd8271ff142")
@@ -49,5 +35,34 @@ final class IncrementalCompilationTests: XCTestCase {
                         previousModTime:  Date(legacyDriverSecsAndNanos: [0, 0]))
           ])
   }
+
+  func testReadSourceFileDependencyGraph() throws {
+    let graph = try SourceFileDependencyGraph(contents: Inputs.fineGrainedSourceFileDependencyGraph)
+
+    graph.verify()
+
+    var found = false
+    graph.forEachNode { node in
+      guard node.sequenceNumber == 10 else { return }
+      found = true
+      XCTAssertEqual(node.key.kind, .nominal)
+      XCTAssertEqual(node.key.aspect, .interface)
+      XCTAssertEqual(node.key.context, "5hello3FooV")
+      XCTAssertTrue(node.key.name.isEmpty)
+      XCTAssertEqual(node.fingerprint, "8daabb8cdf69d8e8702b4788be12efd6")
+      XCTAssertTrue(node.isProvides)
+
+      graph.forEachDefDependedUpon(by: node) { def in
+        XCTAssertTrue(def.sequenceNumber == SourceFileDependencyGraph.sourceFileProvidesInterfaceSequenceNumber)
+        XCTAssertEqual(def.key.kind, .sourceFileProvide)
+        XCTAssertEqual(def.key.aspect, .interface)
+        XCTAssertTrue(def.key.context.isEmpty)
+        XCTAssertTrue(def.key.name.hasSuffix("/hello.swiftdeps"))
+        XCTAssertEqual(def.fingerprint, "85188db3503106210367dbcb7f5d1524")
+        XCTAssertTrue(def.isProvides)
+      }
+    }
+    XCTAssertTrue(found)
+  }
 }