Add ability to build sourcekit-lsp in a unified build

Author: ahoppen

Utilities/build-script-helper.py

@@ -73,6 +73,9 @@ def get_swiftpm_options(swift_exec: str, args: argparse.Namespace) -> List[str]:
         '--configuration', args.configuration,
     ]
 
+    if args.multiroot_data_file:
+        swiftpm_args += ['--multiroot-data-file', args.multiroot_data_file]
+
     if args.verbose:
         swiftpm_args += ['--verbose']
 
@@ -157,13 +160,13 @@ def get_swiftpm_environment_variables(swift_exec: str, args: argparse.Namespace)
     return env
 
 
-def build(swift_exec: str, args: argparse.Namespace) -> None:
+def build_single_product(product: str, swift_exec: str, args: argparse.Namespace) -> None:
     """
     Build one product in the package
     """
     swiftpm_args = get_swiftpm_options(swift_exec, args)
     env = get_swiftpm_environment_variables(swift_exec, args)
-    cmd = [swift_exec, 'build'] + swiftpm_args
+    cmd = [swift_exec, 'build', '--product', product] + swiftpm_args
     check_call(cmd, env=env, verbose=args.verbose)
 
 
@@ -215,7 +218,11 @@ def handle_invocation(swift_exec: str, args: argparse.Namespace) -> None:
     Depending on the action in 'args', build the package, installs the package or run tests.
     """
     if args.action == 'build':
-        build(swift_exec, args)
+        # These products are listed in dependency order. Lower-level targets are listed first.
+        products = ["LSPBindings", "_SourceKitLSP", "sourcekit-lsp"]
+        # Build in reverse dependency order so we can build lower-level targets in parallel.
+        for product in reversed(products):
+            build_single_product(product, swift_exec, args)
     elif args.action == 'test':
         run_tests(swift_exec, args)
     elif args.action == 'install':
@@ -243,6 +250,7 @@ def add_common_args(parser: argparse.ArgumentParser) -> None:
         parser.add_argument('--verbose', '-v', action='store_true', help='enable verbose output')
         parser.add_argument('--cross-compile-host', help='cross-compile for another host instead')
         parser.add_argument('--cross-compile-config', help='an SPM JSON destination file containing Swift cross-compilation flags')
+        parser.add_argument('--multiroot-data-file', help='path to an Xcode workspace to create a unified build of all of Swift\'s SwiftPM projects')
 
     if sys.version_info >= (3, 7, 0):
         subparsers = parser.add_subparsers(title='subcommands', dest='action', required=True, metavar='action')