[build-script.py] Provide an option to pass a custom path to the gyb tool

Author: akyrtzi

build-script.py

@@ -15,7 +15,6 @@
 
 INCR_TRANSFER_ROUNDTRIP_EXEC = \
     WORKSPACE_DIR + '/swift/utils/incrparse/incr_transfer_round_trip.py'
-GYB_EXEC = WORKSPACE_DIR + '/swift/utils/gyb'
 LIT_EXEC = WORKSPACE_DIR + '/llvm-project/llvm/utils/lit/lit.py'
 GROUP_INFO_PATH = PACKAGE_DIR + '/utils/group.json'
 
@@ -84,16 +83,16 @@ def realpath(path):
 
 ## Generating gyb files
 
-def check_gyb_exec():
-    if not os.path.exists(GYB_EXEC):
+def check_gyb_exec(gyb_exec):
+    if not os.path.exists(gyb_exec):
         fatal_error('''
 Error: Could not find gyb.
 Looking at '%s'.
 
 Make sure you have the main swift repo checked out next to the swift-syntax
 repository.
 Refer to README.md for more information.
-''' % GYB_EXEC)
+''' % gyb_exec)
 
 
 def check_rsync():
@@ -102,7 +101,7 @@ def check_rsync():
             fatal_error('Error: Could not find rsync.')
 
 
-def generate_single_gyb_file(gyb_file, output_file_name, destination,
+def generate_single_gyb_file(gyb_exec, gyb_file, output_file_name, destination,
                              temp_files_dir, add_source_locations,
                              additional_gyb_flags, verbose):
   # Source locations are added by default by gyb, and cleared by passing
@@ -112,7 +111,7 @@ def generate_single_gyb_file(gyb_file, output_file_name, destination,
                             else ['--line-directive=']
 
   # Generate the new file
-  check_call([GYB_EXEC] +
+  check_call([gyb_exec] +
              [gyb_file] +
              ['-o', temp_files_dir + '/' + output_file_name] +
              line_directive_flags +
@@ -127,10 +126,10 @@ def generate_single_gyb_file(gyb_file, output_file_name, destination,
              [destination + '/' + output_file_name],
              verbose=verbose)
 
-def generate_gyb_files(verbose, add_source_locations, destination=None):
+def generate_gyb_files(gyb_exec, verbose, add_source_locations, destination=None):
     print('** Generating gyb Files **')
 
-    check_gyb_exec()
+    check_gyb_exec(gyb_exec)
     check_rsync()
 
     swiftsyntax_sources_dir = os.path.join(PACKAGE_DIR, 'Sources',
@@ -175,7 +174,8 @@ def generate_gyb_files(verbose, add_source_locations, destination=None):
         # Slice off the '.gyb' to get the name for the output file
         output_file_name = gyb_file[:-4]
 
-        generate_single_gyb_file(swiftsyntax_sources_dir + '/' + gyb_file,
+        generate_single_gyb_file(gyb_exec,
+                                 swiftsyntax_sources_dir + '/' + gyb_file,
                                  output_file_name, destination,
                                  temp_files_dir, add_source_locations,
                                  additional_gyb_flags=[],
@@ -186,7 +186,7 @@ def generate_gyb_files(verbose, add_source_locations, destination=None):
 
         gyb_file = swiftsyntax_sources_dir + '/SyntaxNodes.swift.gyb.template'
 
-        generate_single_gyb_file(gyb_file, output_file_name,
+        generate_single_gyb_file(gyb_exec, gyb_file, output_file_name,
                                  template_destination, temp_files_dir,
                                  add_source_locations,
                                  additional_gyb_flags=[
@@ -246,11 +246,11 @@ def build(self, product_name, module_group_path=''):
 
 
 ## Testing
-def verify_generated_files(verbose):
+def verify_generated_files(gyb_exec, verbose):
     user_generated_dir = os.path.join(PACKAGE_DIR, 'Sources', 'SwiftSyntax',
                                       'gyb_generated')
     self_generated_dir = tempfile.mkdtemp()
-    generate_gyb_files(verbose=verbose,
+    generate_gyb_files(gyb_exec, verbose=verbose,
                        add_source_locations=False,
                        destination=self_generated_dir)
 
@@ -438,6 +438,8 @@ def main():
 section for arguments that need to be specified for this.
 ''')
 
+    default_gyb_exec = WORKSPACE_DIR + '/swift/utils/gyb'
+
     basic_group = parser.add_argument_group('Basic')
 
     basic_group.add_argument('--build-dir', default=None, help='''
@@ -507,6 +509,9 @@ def main():
       Path to the FileCheck executable that was built as part of the LLVM
       repository. If not specified, it will be looked up from PATH.
       ''')
+    testing_group.add_argument('--gyb-exec', default=default_gyb_exec, help='''
+      Path to the gyb tool. (default: '%s').
+      ''' % (default_gyb_exec) )
     testing_group.add_argument('--verify-generated-files', action='store_true',
                                help='''
       Instead of generating files using gyb, verify that the files which
@@ -533,7 +538,7 @@ def main():
 
     try:
         if not args.verify_generated_files:
-            generate_gyb_files(verbose=args.verbose,
+            generate_gyb_files(args.gyb_exec, verbose=args.verbose,
                                add_source_locations=args.add_source_locations)
         # Skip the rest of the build if we should perform degyb only
         if args.degyb_only:
@@ -546,7 +551,7 @@ def main():
 
     if args.verify_generated_files:
         try:
-            success = verify_generated_files(verbose=args.verbose)
+            success = verify_generated_files(args.gyb_exec, verbose=args.verbose)
         except subprocess.CalledProcessError as e:
             printerr('FAIL: Gyb-generated files committed to repository do '
                      'not match generated ones. Please re-generate the '