Support activating packages from local paths.

sdk/lib/_internal/pub/lib/src/command/global_activate.dart

Index: sdk/lib/_internal/pub/lib/src/command/global_activate.dart
diff --git a/sdk/lib/_internal/pub/lib/src/command/global_activate.dart b/sdk/lib/_internal/pub/lib/src/command/global_activate.dart
index 6fc25e3020d4978e9b1b39330ec8a50bd12be8e7..98ba40e52d2c9fd87929e3c59cda7827ba8a57c0 100644
--- a/sdk/lib/_internal/pub/lib/src/command/global_activate.dart
+++ b/sdk/lib/_internal/pub/lib/src/command/global_activate.dart
@@ -13,34 +13,56 @@ import '../version.dart';
 /// Handles the `global activate` pub command.
 class GlobalActivateCommand extends PubCommand {
   String get description => "Make a package's executables globally available.";
-  String get usage => "pub global activate <package> [version]";
+  String get usage => "pub global activate <package...>";
   bool get takesArguments => true;
 
+  GlobalActivateCommand() {
+    commandParser.addOption("source",
+        abbr: "s",
+        help: "The source used to find the package.",
+        allowed: ["hosted", "path"],
+        defaultsTo: "hosted");
+  }
+
   Future onRun() {
-    // Make sure there is a package.
-    if (commandOptions.rest.isEmpty) {
-      usageError("No package to activate given.");
+    var args = commandOptions.rest;
+
+    readArg([String error]) {
+      if (args.isEmpty) usageError(error);
+      var arg = args.first;
+      args = args.skip(1);
+      return arg;
     }
 
-    // Don't allow extra arguments.
-    if (commandOptions.rest.length > 2) {
-      var unexpected = commandOptions.rest.skip(2).map((arg) => '"$arg"');
+    validateNoExtraArgs() {
+      if (args.isEmpty) return;
+      var unexpected = args.map((arg) => '"$arg"');
       var arguments = pluralize("argument", unexpected.length);
       usageError("Unexpected $arguments ${toSentence(unexpected)}.");
     }
 
-    var package = commandOptions.rest.first;
+    var package = readArg("No package to activate given.");
+
+    switch (commandOptions["source"]) {
+      case "hosted":
+        // Parse the version constraint, if there is one.
+        var constraint = VersionConstraint.any;
+        if (args.isNotEmpty) {
+          try {
+            constraint = new VersionConstraint.parse(readArg());
+          } on FormatException catch (error) {
+            usageError(error.message);
+          }
+        }
+
+        validateNoExtraArgs();
+        return globals.activateHosted(package, constraint);
 
-    // Parse the version constraint, if there is one.
-    var constraint = VersionConstraint.any;
-    if (commandOptions.rest.length == 2) {
-      try {
-        constraint = new VersionConstraint.parse(commandOptions.rest[1]);
-      } on FormatException catch (error) {
-        usageError(error.message);
-      }
+      case "path":
+        validateNoExtraArgs();
+        return globals.activatePath(package);
     }
 
-    return globals.activate(package, constraint);
+    throw "unreachable";
   }
 }