scripts: west-commands: Updates needed when removing ZEPHYR_BASE env

This commit includes the following fixes in order to remove environment
setting of ZEPHYR_BASE is west extension commands.

- Build command
  west build --pristine will now use the ZEPHYR_BASE variable found
  in CMakeCache.txt in the build folder.

  This ensures that the pristine command is executed from the same
  Zephyr that was used for compilation.

- Board command
  The west boards command no longer sets Zephyr base before invoking
  cmake -P cmake/boards.cmake

  Instead boards.cmake uses find_package(Zephyr) to ensure consistent
  behavior with Zephyr samples, so that the detection of Zephyr base is
  uniform across CMake commands.

  It also changes BOARD_ROOT_SPACE_SEPARATED to BOARD_ROOT in order to
  be consistent with existing user documentation.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>

cmake/boards.cmake

@@ -95,18 +95,17 @@ if(CMAKE_SCRIPT_MODE_FILE AND NOT CMAKE_PARENT_LIST_FILE)
 # some other script
 
 # The options available are:
-# BOARD_ROOT_SPACE_SEPARATED: Space-separated board roots
+# BOARD_ROOT: Semi-colon separated board roots
 # FILE_OUT: Set to a file path to save the boards to a file. If not defined the
 #           the contents will be printed to stdout
-if(NOT DEFINED ZEPHYR_BASE)
-  message(FATAL_ERROR "ZEPHYR_BASE not set")
-endif()
+cmake_minimum_required(VERSION 3.13.1)
 
-if (NOT BOARD_ROOT_SPACE_SEPARATED)
-  message(FATAL_ERROR "BOARD_ROOT_SPACE_SEPARATED not defined")
-endif()
+set(NO_BOILERPLATE TRUE)
+find_package(Zephyr HINTS $ENV{ZEPHYR_BASE})
 
-string(REPLACE " " ";" BOARD_ROOT "${BOARD_ROOT_SPACE_SEPARATED}")
+# Appending Zephyr base to list of board roots, as this is also done in boilerplate.cmake.
+# But as this file was executed in script mode, it must also be done here, to give same output.
+list(APPEND BOARD_ROOT ${ZEPHYR_BASE})
 
 if (NOT FILE_OUT)
   set(FILE_OUT FALSE)

scripts/west_commands/boards.py

@@ -4,13 +4,14 @@
 
 import argparse
 import collections
-import os
 import re
 import textwrap
 
 from west import log
 from west.commands import WestCommand
+
 from zcmake import run_cmake
+from zephyr_ext_common import ZEPHYR_CMAKE
 
 class Boards(WestCommand):
 
@@ -54,13 +55,7 @@ class Boards(WestCommand):
         return parser
 
     def do_run(self, args, unknown_args):
-        zb = os.environ.get('ZEPHYR_BASE')
-        if not zb:
-            log.die('Internal error: ZEPHYR_BASE not set in the environment, '
-                    'and should have been by the main script')
-
-        cmake_args = ['-DBOARD_ROOT_SPACE_SEPARATED={}'.format(zb),
-                      '-P', '{}/cmake/boards.cmake'.format(zb)]
+        cmake_args = ['-P', f'{ZEPHYR_CMAKE}/boards.cmake']
         lines = run_cmake(cmake_args, capture_output=True)
         arch_re = re.compile(r'\s*([\w-]+)\:')
         board_re = re.compile(r'\s*([\w-]+)\s*')

scripts/west_commands/build.py

@@ -400,17 +400,12 @@ class Build(Forceable):
 
     def _run_pristine(self):
         _banner('making build dir {} pristine'.format(self.build_dir))
-
-        zb = os.environ.get('ZEPHYR_BASE')
-        if not zb:
-            log.die('Internal error: ZEPHYR_BASE not set in the environment, '
-                    'and should have been by the main script')
-
         if not is_zephyr_build(self.build_dir):
             log.die('Refusing to run pristine on a folder that is not a '
                     'Zephyr build system')
 
-        cmake_args = ['-P', '{}/cmake/pristine.cmake'.format(zb)]
+        cache = CMakeCache.from_build_dir(self.build_dir)
+        cmake_args = ['-P', cache['ZEPHYR_BASE'] + '/cmake/pristine.cmake']
         run_cmake(cmake_args, cwd=self.build_dir, dry_run=self.args.dry_run)
 
     def _run_build(self, target):

scripts/west_commands/sign.py

@@ -18,9 +18,9 @@ from build_helpers import find_build_dir, is_zephyr_build, \
 from runners.core import BuildConfiguration
 from zcmake import CMakeCache
 from zephyr_ext_common import Forceable, cached_runner_config, \
-    zephyr_scripts_path
+    ZEPHYR_SCRIPTS
 
-sys.path.append(os.path.join(zephyr_scripts_path(), 'dts'))
+sys.path.append(str(ZEPHYR_SCRIPTS / 'dts'))
 
 import edtlib
 

scripts/west_commands/zephyr_ext_common.py

@@ -16,6 +16,14 @@ from west.commands import WestCommand
 
 from runners.core import RunnerConfig
 
+# This relies on this file being zephyr/scripts/foo/bar.py.
+# If you move this file, you'll break it, so be careful.
+THIS_ZEPHYR = Path(__file__).parent.parent.parent
+ZEPHYR_BASE = Path(os.environ.get('ZEPHYR_BASE', THIS_ZEPHYR))
+
+# FIXME we need a nicer way to handle imports from scripts and cmake than this.
+ZEPHYR_SCRIPTS = ZEPHYR_BASE / 'scripts'
+ZEPHYR_CMAKE = ZEPHYR_BASE / 'cmake'
 
 class Forceable(WestCommand):
     '''WestCommand subclass for commands with a --force option.'''
@@ -55,12 +63,3 @@ def cached_runner_config(build_dir, cache):
                         elf_file, hex_file, bin_file,
                         gdb=gdb, openocd=openocd,
                         openocd_search=openocd_search)
-
-# FIXME we should think of a nicer way to manage sys.path
-# for shared Zephyr code.
-def zephyr_scripts_path():
-    # This relies on this file being zephyr/scripts/foo/bar.py.
-    zephyr_base = Path(os.environ.get('ZEPHYR_BASE',
-                       Path(__file__).parent.parent.parent))
-
-    return str(zephyr_base / 'scripts')