Improve usability of -l flag

Sources/SwiftDriver/Jobs/CommandLineArguments.swift

@@ -149,6 +149,17 @@ extension Array where Element == Job.ArgTemplate {
     }
   }
 
+  /// Append all parsed options from the given groups except from excludeList to this command line.
+  mutating func appendAllExcept(includeList: [Option.Group], excludeList: [Option], from parsedOptions: inout ParsedOptions) throws {
+    for group in includeList{
+      for optGroup in parsedOptions.arguments(in: group){
+        if !excludeList.contains(where: {$0 == optGroup.option}) {
+          try append(optGroup)
+        }
+      }
+    }
+  }
+
   /// Append the last of the given flags that appears in the parsed options,
   /// or the flag that corresponds to the default value if neither
   /// appears.

Sources/SwiftDriver/Jobs/DarwinToolchain+LinkerSupport.swift

@@ -422,9 +422,12 @@ extension DarwinToolchain {
 
     // These custom arguments should be right before the object file at the
     // end.
-    try commandLine.append(
-      contentsOf: parsedOptions.arguments(in: .linkerOption)
+    try commandLine.appendAllExcept(
+      includeList: [.linkerOption],
+      excludeList: [.l],
+      from: &parsedOptions
     )
+    addLinkedLibArgs(to: &commandLine, parsedOptions: &parsedOptions)
     try commandLine.appendAllArguments(.Xlinker, from: &parsedOptions)
   }
 }

Sources/SwiftDriver/Jobs/GenericUnixToolchain+LinkerSupport.swift

@@ -274,9 +274,12 @@ extension GenericUnixToolchain {
 
       // These custom arguments should be right before the object file at the
       // end.
-      try commandLine.append(
-        contentsOf: parsedOptions.arguments(in: .linkerOption)
+      try commandLine.appendAllExcept(
+        includeList: [.linkerOption],
+        excludeList: [.l],
+        from: &parsedOptions
       )
+      addLinkedLibArgs(to: &commandLine, parsedOptions: &parsedOptions)
       // Because we invoke `clang` as the linker executable, we must still
       // use `-Xlinker` for linker-specific arguments.
       for linkerOpt in parsedOptions.arguments(for: .Xlinker) {

Sources/SwiftDriver/Jobs/InterpretJob.swift

@@ -31,7 +31,8 @@ extension Driver {
     // FIXME: MSVC runtime flags
 
     try commandLine.appendLast(.parseSil, from: &parsedOptions)
-    try commandLine.appendAll(.l, .framework, from: &parsedOptions)
+    toolchain.addLinkedLibArgs(to: &commandLine, parsedOptions: &parsedOptions)
+    try commandLine.appendAll(.framework, from: &parsedOptions)
 
     // The immediate arguments must be last.
     try commandLine.appendLast(.DASHDASH, from: &parsedOptions)

Sources/SwiftDriver/Jobs/ReplJob.swift

@@ -19,7 +19,11 @@ extension Driver {
     // FIXME: MSVC runtime flags
 
     try commandLine.appendLast(.importObjcHeader, from: &parsedOptions)
-    try commandLine.appendAll(.l, .framework, .L, from: &parsedOptions)
+    toolchain.addLinkedLibArgs(
+      to: &commandLine,
+      parsedOptions: &parsedOptions
+    )
+    try commandLine.appendAll(.framework, .L, from: &parsedOptions)
 
     // Squash important frontend options into a single argument for LLDB.
     let lldbCommandLine: [Job.ArgTemplate] = [.squashedArgumentList(option: "--repl=", args: commandLine)]

Sources/SwiftDriver/Jobs/Toolchain+LinkerSupport.swift

@@ -86,6 +86,15 @@ extension Toolchain {
     ).appending(component: runtimeName)
     return try fileSystem.exists(path)
   }
+
+  func addLinkedLibArgs(
+    to commandLine: inout [Job.ArgTemplate],
+    parsedOptions: inout ParsedOptions
+  ) {
+    for match in parsedOptions.arguments(for: .l) {
+      commandLine.appendFlag(match.option.spelling + match.argument.asSingle)
+    }
+  }
 }
 
 // MARK: - Common argument routines

Sources/SwiftDriver/Jobs/WebAssemblyToolchain+LinkerSupport.swift

@@ -139,9 +139,12 @@ extension WebAssemblyToolchain {
 
       // These custom arguments should be right before the object file at the
       // end.
-      try commandLine.append(
-        contentsOf: parsedOptions.arguments(in: .linkerOption)
+      try commandLine.appendAllExcept(
+        includeList: [.linkerOption],
+        excludeList: [.l],
+        from: &parsedOptions
       )
+      addLinkedLibArgs(to: &commandLine, parsedOptions: &parsedOptions)
       try commandLine.appendAllArguments(.Xlinker, from: &parsedOptions)
       try commandLine.appendAllArguments(.XclangLinker, from: &parsedOptions)
 

Sources/SwiftOptions/Options.swift

@@ -389,7 +389,7 @@ extension Option {
   public static let ltoLibrary: Option = Option("-lto-library", .separate, attributes: [.frontend, .argumentIsPath], metaVar: "<lto-library>", helpText: "Perform LTO with <lto-library>")
   public static let lto: Option = Option("-lto=", .joined, attributes: [.frontend, .noInteractive], helpText: "Specify the LTO type to either 'llvm-thin' or 'llvm-full'")
   public static let L: Option = Option("-L", .joinedOrSeparate, attributes: [.frontend, .doesNotAffectIncrementalBuild, .argumentIsPath], helpText: "Add directory to library link search path", group: .linkerOption)
-  public static let l: Option = Option("-l", .joined, attributes: [.frontend, .doesNotAffectIncrementalBuild], helpText: "Specifies a library which should be linked against", group: .linkerOption)
+  public static let l: Option = Option("-l", .joinedOrSeparate, attributes: [.frontend, .doesNotAffectIncrementalBuild], helpText: "Specifies a library which should be linked against", group: .linkerOption)
   public static let mergeModules: Option = Option("-merge-modules", .flag, attributes: [.frontend, .noDriver], helpText: "Merge the input modules without otherwise processing them", group: .modes)
   public static let migrateKeepObjcVisibility: Option = Option("-migrate-keep-objc-visibility", .flag, attributes: [.frontend, .noInteractive], helpText: "When migrating, add '@objc' to declarations that would've been implicitly visible in Swift 3")
   public static let migratorUpdateSdk: Option = Option("-migrator-update-sdk", .flag, attributes: [.frontend, .noInteractive], helpText: "Does nothing. Temporary compatibility flag for Xcode.")

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -1016,6 +1016,7 @@ final class SwiftDriverTests: XCTestCase {
     env["SWIFT_DRIVER_DSYMUTIL_EXEC"] = "/garbage/dsymutil"
 
     let commonArgs = ["swiftc", "foo.swift", "bar.swift",  "-module-name", "Test"]
+
     do {
       // macOS target
       var driver = try Driver(args: commonArgs + ["-emit-library", "-target", "x86_64-apple-macosx10.15"], env: env)
@@ -1456,6 +1457,16 @@ final class SwiftDriverTests: XCTestCase {
         XCTAssertFalse(cmd.contains(.flag("-shared")))
       }
     }
+
+    do {
+      // Linker flags with and without space
+      var driver = try Driver(args: commonArgs + ["-lsomelib","-l","otherlib"], env: env)
+      let plannedJobs = try driver.planBuild()
+      let cmd = plannedJobs.last!.commandLine
+      XCTAssertTrue(cmd.contains(.flag("-lsomelib")))
+      XCTAssertTrue(cmd.contains(.flag("-lotherlib")))
+    }
+
   }
 
   func testWebAssemblyUnsupportedFeatures() throws {
@@ -2346,6 +2357,20 @@ final class SwiftDriverTests: XCTestCase {
         XCTAssertEqual(error as? PlanningError, .replReceivedInput)
       }
     }
+
+    do {
+      // Linked library arguments with space
+      var driver = try Driver(args: ["swift", "-repl", "-l", "somelib", "-lotherlib"])
+      let plannedJobs = try driver.planBuild()
+      XCTAssertEqual(plannedJobs.count, 1)
+      let cmd = plannedJobs.first!.commandLine
+      guard case let .squashedArgumentList(option: _, args: args) = cmd[0] else {
+        XCTFail()
+        return
+      }
+      XCTAssertTrue(args.contains(.flag("-lsomelib")))
+      XCTAssertTrue(args.contains(.flag("-lotherlib")))
+    }
   }
 
   func testInstallAPI() throws {
@@ -2411,7 +2436,7 @@ final class SwiftDriverTests: XCTestCase {
     }
 
     do {
-      var driver = try Driver(args: ["swift", "-L/path/to/lib", "-F/path/to/framework", "foo.swift"])
+      var driver = try Driver(args: ["swift", "-L/path/to/lib", "-F/path/to/framework", "-lsomelib", "-l", "otherlib", "foo.swift"])
       let plannedJobs = try driver.planBuild()
       XCTAssertEqual(plannedJobs.count, 1)
       let job = plannedJobs[0]
@@ -2425,6 +2450,9 @@ final class SwiftDriverTests: XCTestCase {
       if driver.targetTriple.isDarwin {
         XCTAssertTrue(job.extraEnvironment.contains { $0 == "DYLD_FRAMEWORK_PATH" && $1.contains("/path/to/framework") })
       }
+
+      XCTAssertTrue(job.commandLine.contains(.flag("-lsomelib")))
+      XCTAssertTrue(job.commandLine.contains(.flag("-lotherlib")))
     }
   }