Does a better job about getting timing for installing generated heade…

…rs by throwing it out on a thread.

DELTA=20 (4 added, 8 deleted, 8 changed)
DELTA_BY_EXTENSION=py=12
PiperOrigin-RevId: 203025058

src/TulsiGenerator/Bazel/tulsi/tulsi_aspects.bzl

@@ -494,7 +494,8 @@ def _minimum_os_for_platform(ctx, platform_type_str):
         return min_os
 
     platform_type = getattr(apple_common.platform_type, platform_type_str)
-    min_os = (ctx.attr._tulsi_xcode_config[apple_common.XcodeVersionConfig].minimum_os_for_platform_type(platform_type))
+    min_os = (ctx.attr._tulsi_xcode_config[apple_common.XcodeVersionConfig]
+        .minimum_os_for_platform_type(platform_type))
 
     if not min_os:
         return None

src/TulsiGenerator/Scripts/bazel_build.py

@@ -28,6 +28,7 @@
 import subprocess
 import sys
 import textwrap
+import threading
 import time
 import zipfile
 
@@ -680,25 +681,18 @@ def Run(self, args):
     if exit_code:
       return exit_code
 
-    # We expect artifact installation to take longer than header installation,
-    # so we spawn the genfiles installation subprocess first, spawn and wait on
-    # artifact installation, and then finally wait on genfiles installation
-    # (which is hopefully already done). Note that this makes the timer for
-    # genfiles installation inaccurate (it will always be longer than the
-    # artifact installation timer).
-    genfiles_timer = Timer('Installing generated headers',
-                           'installing_generated_headers').Start()
-    genfiles_process = self._StartInstallingGeneratedHeaders(outputs)
-
+    # Generated headers are installed on a thread since we are launching
+    # a separate process to do so. This gives us clean timings.
+    install_thread = threading.Thread(
+        target=self._StartInstallingGeneratedHeaders, args=(outputs,))
+    install_thread.start()
     timer = Timer('Installing artifacts', 'installing_artifacts').Start()
     exit_code = self._InstallArtifact(outputs_data)
     timer.End()
+    install_thread.join()
     if exit_code:
       return exit_code
 
-    genfiles_process.wait()
-    genfiles_timer.End()
-
     exit_code, dsym_paths = self._InstallDSYMBundles(
         self.built_products_dir, outputs_data)
     if exit_code:
@@ -1147,9 +1141,10 @@ def _FindEmbeddedBundle(self, bundle_name, bundle_extension, bundle_path):
         return path
     return None
 
-  def _StartInstallingGeneratedHeaders(self, outputs):
+  def _InstallGeneratedHeaders(self, outputs):
     """Invokes install_genfiles.py to install generated Bazel files."""
-
+    genfiles_timer = Timer('Installing generated headers',
+                           'installing_generated_headers').Start()
     # Resolve the path to the install_genfiles.py script.
     # It should be in the same directory as this script.
     path = os.path.join(os.path.dirname(os.path.realpath(__file__)),
@@ -1161,7 +1156,8 @@ def _StartInstallingGeneratedHeaders(self, outputs):
     self._PrintVerbose('Spawning subprocess install_genfiles.py to copy '
                        'generated files in the background...')
     process = subprocess.Popen(args)
-    return process
+    process.wait()
+    genfiles_timer.End()
 
   def _InstallBundle(self, source_path, output_path):
     """Copies the bundle at source_path to output_path."""