sourcekit-lsp/Sources/SourceKitLSP/Swift/OpenInterface.swift

//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2022 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
//
//===----------------------------------------------------------------------===//

#if compiler(>=6)
import Foundation
package import LanguageServerProtocol
import SKLogging
import SKSupport
import SourceKitD
#else
import Foundation
import LanguageServerProtocol
import SKLogging
import SKSupport
import SourceKitD
#endif

struct GeneratedInterfaceInfo {
  var contents: String
}

extension SwiftLanguageService {
  package func openGeneratedInterface(
    document: DocumentURI,
    moduleName: String,
    groupName: String?,
    symbolUSR symbol: String?
  ) async throws -> GeneratedInterfaceDetails? {
    // Name of interface module name with group names appended
    let name =
      if let groupName {
        "\(moduleName).\(groupName.replacing("/", with: "."))"
      } else {
        moduleName
      }
    let interfaceFilePath = self.generatedInterfacesPath.appendingPathComponent("\(name).swiftinterface")
    let interfaceDocURI = DocumentURI(interfaceFilePath)
    // has interface already been generated
    if let snapshot = try? await self.latestSnapshot(for: interfaceDocURI) {
      return await self.generatedInterfaceDetails(
        uri: interfaceDocURI,
        snapshot: snapshot,
        symbol: symbol
      )
    } else {
      let interfaceInfo = try await self.generatedInterfaceInfo(
        document: document,
        moduleName: moduleName,
        groupName: groupName,
        interfaceURI: interfaceDocURI
      )
      try interfaceInfo.contents.write(to: interfaceFilePath, atomically: true, encoding: String.Encoding.utf8)
      let snapshot = DocumentSnapshot(
        uri: interfaceDocURI,
        language: .swift,
        version: 0,
        lineTable: LineTable(interfaceInfo.contents)
      )
      let result = await self.generatedInterfaceDetails(
        uri: interfaceDocURI,
        snapshot: snapshot,
        symbol: symbol
      )
      _ = await orLog("Closing generated interface") {
        try await sendSourcekitdRequest(closeDocumentSourcekitdRequest(uri: interfaceDocURI), fileContents: nil)
      }
      return result
    }
  }

  /// Open the Swift interface for a module.
  ///
  /// - Parameters:
  ///   - document: The document whose compiler arguments should be used to generate the interface.
  ///   - moduleName: The module to generate an index for.
  ///   - groupName: The module group name.
  ///   - interfaceURI: The file where the generated interface should be written.
  ///
  /// - Important: This opens a document with name `interfaceURI.pseudoPath` in sourcekitd. The caller is responsible
  ///   for ensuring that the document will eventually get closed in sourcekitd again.
  private func generatedInterfaceInfo(
    document: DocumentURI,
    moduleName: String,
    groupName: String?,
    interfaceURI: DocumentURI
  ) async throws -> GeneratedInterfaceInfo {
    let keys = self.keys
    let skreq = sourcekitd.dictionary([
      keys.request: requests.editorOpenInterface,
      keys.moduleName: moduleName,
      keys.groupName: groupName,
      keys.name: interfaceURI.pseudoPath,
      keys.synthesizedExtension: 1,
      keys.compilerArgs: await self.buildSettings(for: document, fallbackAfterTimeout: false)?.compilerArgs
        as [SKDRequestValue]?,
    ])

    let dict = try await sendSourcekitdRequest(skreq, fileContents: nil)
    return GeneratedInterfaceInfo(contents: dict[keys.sourceText] ?? "")
  }

  private func generatedInterfaceDetails(
    uri: DocumentURI,
    snapshot: DocumentSnapshot,
    symbol: String?
  ) async -> GeneratedInterfaceDetails {
    do {
      guard let symbol = symbol else {
        return GeneratedInterfaceDetails(uri: uri, position: nil)
      }
      let keys = self.keys
      let skreq = sourcekitd.dictionary([
        keys.request: requests.editorFindUSR,
        keys.sourceFile: uri.sourcekitdSourceFile,
        keys.primaryFile: uri.primaryFile?.pseudoPath,
        keys.usr: symbol,
      ])

      let dict = try await sendSourcekitdRequest(skreq, fileContents: snapshot.text)
      if let offset: Int = dict[keys.offset] {
        return GeneratedInterfaceDetails(uri: uri, position: snapshot.positionOf(utf8Offset: offset))
      } else {
        return GeneratedInterfaceDetails(uri: uri, position: nil)
      }
    } catch {
      return GeneratedInterfaceDetails(uri: uri, position: nil)
    }
  }
}