Merge pull request #462 from CodaFi/a-serial-case

Serialize Fingerprint Blobs For External Dependencies

Author: CodaFi

Sources/SwiftDriver/IncrementalCompilation/DependencyKey.swift

@@ -4,13 +4,17 @@ import Foundation
 /// A filename from another module
 /*@_spi(Testing)*/ public struct ExternalDependency: Hashable, Comparable, CustomStringConvertible {
   let fileName: String
+  let fingerprint: String?
+
+  /*@_spi(Testing)*/ public init(_ fileName: String, fingerprint: String? = nil) {
+    self.fileName = fileName
+    self.fingerprint = fingerprint
+  }
 
   var file: VirtualPath? {
     try? VirtualPath(path: fileName)
   }
-  /*@_spi(Testing)*/ public init(_ path: String) {
-    self.fileName = path
-  }
+
   public var description: String {
     fileName.description
   }

Sources/SwiftDriver/IncrementalCompilation/ModuleDependencyGraph.swift

@@ -561,13 +561,17 @@ extension ModuleDependencyGraph {
           }
           self.nodeUses[key, default: []].append(Int(record.fields[0]))
         case .externalDepNode:
-          guard record.fields.count == 1,
-                record.fields[0] < identifiers.count
+          guard record.fields.count == 2,
+                record.fields[0] < identifiers.count,
+                case .blob(let fingerprintBlob) = record.payload,
+                let fingerprintStr = String(data: fingerprintBlob, encoding: .utf8)
           else {
             throw ReadError.malformedExternalDepNodeRecord
           }
           let path = identifiers[Int(record.fields[0])]
-          self.graph.externalDependencies.insert(ExternalDependency(path))
+          let hasFingerprint = Int(record.fields[1]) != 0
+          let fingerprint = hasFingerprint ? fingerprintStr : nil
+          self.graph.externalDependencies.insert(ExternalDependency(path, fingerprint: fingerprint))
         case .identifierNode:
           guard record.fields.count == 0,
                 case .blob(let identifierBlob) = record.payload,
@@ -804,6 +808,10 @@ extension ModuleDependencyGraph {
         .literal(RecordID.externalDepNode.rawValue),
         // path ID
         .vbr(chunkBitWidth: 13),
+        // fingerprint?
+        .fixed(bitWidth: 1),
+        // fingerprint bytes
+        .blob
       ])
       self.abbreviate(.identifierNode, [
         .literal(RecordID.identifierNode.rawValue),
@@ -874,10 +882,11 @@ extension ModuleDependencyGraph {
         }
 
         for dep in graph.externalDependencies {
-          serializer.stream.writeRecord(serializer.abbreviations[.externalDepNode]!) {
+          serializer.stream.writeRecord(serializer.abbreviations[.externalDepNode]!, {
             $0.append(RecordID.externalDepNode)
             $0.append(serializer.lookupIdentifierCode(for: dep.fileName))
-          }
+            $0.append((dep.fingerprint != nil) ? UInt32(1) : UInt32(0))
+          }, blob: dep.fingerprint ?? "")
         }
       }
       return ByteString(serializer.stream.data)

Tests/SwiftDriverTests/DependencyGraphSerializationTests.swift

@@ -49,7 +49,7 @@ class DependencyGraphSerializationTests: XCTestCase {
       var commands: [LoadCommand]
 
       enum LoadCommand {
-        case load(index: Int, nodes: [MockDependencyKind: [String]])
+        case load(index: Int, nodes: [MockDependencyKind: [String]], fingerprint: String? = nil)
         case reload(index: Int, nodes: [MockDependencyKind: [String]], fingerprint: String? = nil)
       }
     }
@@ -212,15 +212,19 @@ class DependencyGraphSerializationTests: XCTestCase {
         .load(index: 6, nodes: [.nominal: ["C2->"]]),
         .reload(index: 0, nodes: [.nominal: ["A1@11", "A2@2"]])
       ]),
+      GraphFixture(commands: [
+        .load(index: 0, nodes: [.externalDepend: ["/foo->", "/bar->"]], fingerprint: "ABCDEFG"),
+        .reload(index: 0, nodes: [.externalDepend: ["/foo->", "/bar->"]], fingerprint: "HIJKLMNOP"),
+      ]),
     ]
 
     for fixture in fixtures {
       let de = DiagnosticsEngine()
       let graph = ModuleDependencyGraph(mock: de)
       for loadCommand in fixture.commands {
         switch loadCommand {
-        case .load(index: let index, nodes: let nodes):
-          graph.simulateLoad(index, nodes, nil)
+        case .load(index: let index, nodes: let nodes, fingerprint: let fingerprint):
+          graph.simulateLoad(index, nodes, fingerprint)
         case .reload(index: let index, nodes: let nodes, fingerprint: let fingerprint):
           _ = graph.simulateReload(index, nodes, fingerprint)
         }