ninja/win: Put common msvs_system_include_dirs into %INCLUDE%

pylib/gyp/msvs_emulation.py

Index: pylib/gyp/msvs_emulation.py
diff --git a/pylib/gyp/msvs_emulation.py b/pylib/gyp/msvs_emulation.py
index 63593a424d8a792fca896b025cd8e674c438c439..1b82adba16364fd2efd13c62ae5447d35bca22ff 100644
--- a/pylib/gyp/msvs_emulation.py
+++ b/pylib/gyp/msvs_emulation.py
@@ -12,6 +12,7 @@ import re
 import subprocess
 import sys
 
+from gyp.common import OrderedSet
 import gyp.MSVSVersion
 
 windows_quoter_regex = re.compile(r'(\\*)"')
@@ -131,6 +132,54 @@ def _FindDirectXInstallation():
   return dxsdk_dir
 
 
+def GetGlobalVSMacroEnv(vs_version):
+  """Get a dict of variables mapping internal VS macro names to their gyp
+  equivalents. Returns all variables that are independent of the target."""
+  env = {}
+  # '$(VSInstallDir)' and '$(VCInstallDir)' are available when and only when
+  # Visual Studio is actually installed.
+  if vs_version.Path():
+    env['$(VSInstallDir)'] = vs_version.Path()
+    env['$(VCInstallDir)'] = os.path.join(vs_version.Path(), 'VC') + '\\'
+  # Chromium uses DXSDK_DIR in include/lib paths, but it may or may not be
+  # set. This happens when the SDK is sync'd via src-internal, rather than
+  # by typical end-user installation of the SDK. If it's not set, we don't
+  # want to leave the unexpanded variable in the path, so simply strip it.
+  dxsdk_dir = _FindDirectXInstallation()
+  env['$(DXSDK_DIR)'] = dxsdk_dir if dxsdk_dir else ''
+  # Try to find an installation location for the Windows DDK by checking
+  # the WDK_DIR environment variable, may be None.
+  env['$(WDK_DIR)'] = os.environ.get('WDK_DIR', '')
+  return env
+
+def ExtractSharedMSVSSystemIncludes(configs, generator_flags):
+  """Finds msvs_system_include_dirs that are common to all targets, removes
+  them from all targets, and returns an OrderedSet containing them."""
+  all_system_includes = OrderedSet(
+      configs[0].get('msvs_system_include_dirs', []))
+  for config in configs[1:]:
+    system_includes = config.get('msvs_system_include_dirs', [])
+    all_system_includes = all_system_includes & OrderedSet(system_includes)
+  if not all_system_includes:
+    return None
+  # Expand macros in all_system_includes.
+  env = GetGlobalVSMacroEnv(GetVSVersion(generator_flags))
+  expanded_system_includes = OrderedSet([ExpandMacros(include, env)
+                                         for include in all_system_includes])
+  if any(['$' in include for include in expanded_system_includes]):
+    # Some path relies on target-specific variables, bail.
+    return None
+
+  # Remove system includes shared by all targets from the targets.
+  for config in configs:
+    includes = config.get('msvs_system_include_dirs', [])
+    if includes:  # Don't insert a msvs_system_include_dirs key if not needed.
+      # This must check the unexpanded includes list:
+      new_includes = [i for i in includes if i not in all_system_includes]
+      config['msvs_system_include_dirs'] = new_includes
+  return expanded_system_includes
+
+
 class MsvsSettings(object):
   """A class that understands the gyp 'msvs_...' values (especially the
   msvs_settings field). They largely correpond to the VS2008 IDE DOM. This
@@ -139,11 +188,6 @@ class MsvsSettings(object):
   def __init__(self, spec, generator_flags):
     self.spec = spec
     self.vs_version = GetVSVersion(generator_flags)
-    self.dxsdk_dir = _FindDirectXInstallation()
-
-    # Try to find an installation location for the Windows DDK by checking
-    # the WDK_DIR environment variable, may be None.
-    self.wdk_dir = os.environ.get('WDK_DIR')
 
     supported_fields = [
         ('msvs_configuration_attributes', dict),
@@ -194,18 +238,7 @@ class MsvsSettings(object):
         '$(PlatformName)': target_platform,
         '$(ProjectDir)\\': '',
     }
-    # '$(VSInstallDir)' and '$(VCInstallDir)' are available when and only when
-    # Visual Studio is actually installed.
-    if self.vs_version.Path():
-      replacements['$(VSInstallDir)'] = self.vs_version.Path()
-      replacements['$(VCInstallDir)'] = os.path.join(self.vs_version.Path(),
-                                                     'VC') + '\\'
-    # Chromium uses DXSDK_DIR in include/lib paths, but it may or may not be
-    # set. This happens when the SDK is sync'd via src-internal, rather than
-    # by typical end-user installation of the SDK. If it's not set, we don't
-    # want to leave the unexpanded variable in the path, so simply strip it.
-    replacements['$(DXSDK_DIR)'] = self.dxsdk_dir if self.dxsdk_dir else ''
-    replacements['$(WDK_DIR)'] = self.wdk_dir if self.wdk_dir else ''
+    replacements.update(GetGlobalVSMacroEnv(self.vs_version))
     return replacements
 
   def ConvertVSMacros(self, s, base_to_build=None, config=None):
@@ -897,7 +930,8 @@ def _ExtractCLPath(output_of_where):
     if line.startswith('LOC:'):
       return line[len('LOC:'):].strip()
 
-def GenerateEnvironmentFiles(toplevel_build_dir, generator_flags, open_out):
+def GenerateEnvironmentFiles(toplevel_build_dir, generator_flags,
+                             system_includes, open_out):
   """It's not sufficient to have the absolute path to the compiler, linker,
   etc. on Windows, as those tools rely on .dlls being in the PATH. We also
   need to support both x86 and x64 compilers within the same build (to support
@@ -928,6 +962,13 @@ def GenerateEnvironmentFiles(toplevel_build_dir, generator_flags, open_out):
         args, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     variables, _ = popen.communicate()
     env = _ExtractImportantEnvironment(variables)
+
+    # Inject system includes from gyp files into INCLUDE.
+    if system_includes:
+      system_includes = system_includes | OrderedSet(
+                                              env.get('INCLUDE', '').split(';'))
+      env['INCLUDE'] = ';'.join(system_includes)
+
     env_block = _FormatAsEnvironmentBlock(env)
     f = open_out(os.path.join(toplevel_build_dir, 'environment.' + arch), 'wb')
     f.write(env_block)