Update help to use multiline strings.

Author: thomasvl

Sources/protoc-gen-swift/main.swift

@@ -79,52 +79,51 @@ struct GeneratorPlugin {
   }
 
   private func showHelp() {
-    print("\(CommandLine.programName): Convert parsed proto definitions into Swift")
-    print("")
-    showVersion()
-    print(Version.copyright)
-    print("")
-
     let version = SwiftProtobuf.Version.self
     let packageVersion = "\(version.major),\(version.minor),\(version.revision)"
 
-    let help = (
-      "Note:  This is a plugin for protoc and should not normally be run\n"
-        + "directly.\n"
-        + "\n"
-        + "If you invoke a recent version of protoc with the --swift_out=<dir>\n"
-        + "option, then protoc will search the current PATH for protoc-gen-swift\n"
-        + "and use it to generate Swift output.\n"
-        + "\n"
-        + "In particular, if you have renamed this program, you will need to\n"
-        + "adjust the protoc command-line option accordingly.\n"
-        + "\n"
-        + "The generated Swift output requires the SwiftProtobuf \(SwiftProtobuf.Version.versionString)\n"
-        + "library be included in your project.\n"
-        + "\n"
-        + "If you use `swift build` to compile your project, add this to\n"
-        + "Package.swift:\n"
-        + "\n"
-        + "   dependencies: [\n"
-        + "     .package(name: \"SwiftProtobuf\", url: \"https://github.com/apple/swift-protobuf.git\", from: \"\(packageVersion)\"),"
-        + "   ]\n"
-        + "\n"
-        + "\n"
-        + "Usage: \(CommandLine.programName) [options] [filename...]\n"
-        + "\n"
-        + " -h|--help:  Print this help message\n"
-        + " --version: Print the program version\n"
-        + "\n"
-        + "Filenames specified on the command line indicate binary-encoded\n"
-        + "google.protobuf.compiler.CodeGeneratorRequest objects that will\n"
-        + "be read and converted to Swift source code.  The source text will be\n"
-        + "written directly to stdout.\n"
-        + "\n"
-        + "When invoked with no filenames, it will read a single binary-encoded\n"
-        + "google.protobuf.compiler.CodeGeneratorRequest object from stdin and\n"
-        + "emit the corresponding CodeGeneratorResponse object to stdout.\n")
-
-    print(help)
+    print("""
+      \(CommandLine.programName): Convert parsed proto definitions into Swift
+
+      """)
+    showVersion()
+    print("""
+      \(Version.copyright)
+
+      Note:  This is a plugin for protoc and should not normally be run
+      directly.
+
+      If you invoke a recent version of protoc with the --swift_out=<dir>
+      option, then protoc will search the current PATH for protoc-gen-swift
+      and use it to generate Swift output.
+
+      In particular, if you have renamed this program, you will need to
+      adjust the protoc command-line option accordingly.
+
+      The generated Swift output requires the SwiftProtobuf \(SwiftProtobuf.Version.versionString)
+      library be included in your project.
+
+      If you use `swift build` to compile your project, add this to
+      Package.swift:
+
+         dependencies: [
+           .package(name: "SwiftProtobuf", url: "https://github.com/apple/swift-protobuf.git", from: "\(packageVersion)"),
+         ]
+
+      Usage: \(CommandLine.programName) [options] [filename...]
+
+        -h|--help:  Print this help message
+        --version: Print the program version
+
+      Filenames specified on the command line indicate binary-encoded
+      google.protobuf.compiler.CodeGeneratorRequest objects that will
+      be read and converted to Swift source code.  The source text will be
+      written directly to stdout.
+
+      When invoked with no filenames, it will read a single binary-encoded
+      google.protobuf.compiler.CodeGeneratorRequest object from stdin and
+      emit the corresponding CodeGeneratorResponse object to stdout.
+      """)
   }
 
   private func showVersion() {