#3 Replaced ar with tool object.

source/fab/newtools/__init__.py

@@ -7,6 +7,7 @@
 '''A simple init file to make it shorter to import tools.
 '''
 
+from fab.newtools.ar import Ar
 from fab.newtools.categories import Categories
 from fab.newtools.compiler import (CCompiler, Compiler, FortranCompiler, Gcc,
                                    Gfortran, Icc, Ifort)
@@ -19,7 +20,8 @@
 from fab.newtools.tool_box import ToolBox
 from fab.newtools.versioning import Fcm, Git, Subversion, Versioning
 
-__all__ = ["Categories",
+__all__ = ["Ar",
+           "Categories",
            "CCompiler",
            "Compiler",
            "Cpp",

source/fab/newtools/ar.py

@@ -0,0 +1,46 @@
+##############################################################################
+# (c) Crown copyright Met Office. All rights reserved.
+# For further details please refer to the file COPYRIGHT
+# which you should have received as part of this distribution
+##############################################################################
+
+"""This file contains the base class for any preprocessor, and two derived
+classes for cpp and fpp.
+
+"""
+
+from pathlib import Path
+from typing import List, Union
+
+from fab.newtools.categories import Categories
+from fab.newtools.tool import Tool
+
+
+class Ar(Tool):
+    '''This is the base class for `ar`.
+    '''
+
+    def __init__(self):
+        super().__init__("ar", "ar", Categories.AR)
+
+    def check_available(self):
+        '''Checks if the compiler is available. We do this by requesting the
+        compiler version.
+        '''
+        try:
+            self.run("--version")
+        except (RuntimeError, FileNotFoundError):
+            return False
+        return True
+
+    def create(self, output_fpath: Path,
+               members: List[Union[Path, str]]):
+        '''Create the archive with the specified name, containing the
+        listed members.
+        :param output_fpath: the output path.
+        :param members: the list of objects to be added to the archive.
+        '''
+        print("XX", type(members), type(map(str, members)))
+        parameters = ["cr", str(output_fpath)]
+        parameters.extend(map(str, members))
+        return self.run(additional_parameters=parameters)

source/fab/newtools/categories.py

@@ -22,6 +22,7 @@ class Categories(Enum):
     FCM = auto()
     GIT = auto()
     SUBVERSION = auto()
+    AR = auto()
 
     def __str__(self):
         '''Simplify the str output by using only the name (e.g. `C_COMPILER`

source/fab/newtools/tool_repository.py

@@ -14,7 +14,7 @@
 import logging
 from typing import Any, Type
 
-from fab.newtools import (Categories, Cpp, CppFortran, Gcc, Gfortran,
+from fab.newtools import (Ar, Categories, Cpp, CppFortran, Gcc, Gfortran,
                           Icc, Ifort, Linker)
 from fab.newtools.versioning import Fcm, Git, Subversion
 
@@ -56,7 +56,7 @@ def __init__(self):
         # TODO: sort the defaults so that they actually work (since not all
         # tools FAB knows about are available). For now, disable Fpp:
         for cls in [Gcc, Icc, Gfortran, Ifort, Cpp, CppFortran,
-                    Fcm, Git, Subversion]:
+                    Fcm, Git, Subversion, Ar]:
             self.add_tool(cls)
 
     def add_tool(self, cls: Type[Any]):

source/fab/steps/archive_objects.py

@@ -16,7 +16,7 @@
 from fab.constants import OBJECT_FILES, OBJECT_ARCHIVES
 from fab.steps import step
 from fab.util import log_or_dot
-from fab.tools import run_command
+from fab.newtools import Categories
 from fab.artefacts import ArtefactsGetter, CollectionGetter
 
 logger = logging.getLogger(__name__)
@@ -30,8 +30,10 @@
 # todo: all this documentation for such a simple step - should we split it up somehow?
 
 @step
-def archive_objects(config: BuildConfig, source: Optional[ArtefactsGetter] = None, archiver='ar',
-                    output_fpath=None, output_collection=OBJECT_ARCHIVES):
+def archive_objects(config: BuildConfig,
+                    source: Optional[ArtefactsGetter] = None,
+                    output_fpath=None,
+                    output_collection=OBJECT_ARCHIVES):
     """
     Create an object archive for every build target, from their object files.
 
@@ -91,9 +93,8 @@ def archive_objects(config: BuildConfig, source: Optional[ArtefactsGetter] = Non
     # todo: the output path should not be an abs fpath, it should be relative to the proj folder
 
     source_getter = source or DEFAULT_SOURCE_GETTER
-    archiver = archiver
+    ar = config.tool_box[Categories.AR]
     output_fpath = str(output_fpath) if output_fpath else None
-    output_collection = output_collection
 
     target_objects = source_getter(config.artefact_store)
     assert target_objects.keys()
@@ -114,14 +115,11 @@ def archive_objects(config: BuildConfig, source: Optional[ArtefactsGetter] = Non
             output_fpath = Template(str(output_fpath)).substitute(
                 output=config.build_output)
 
-        command = [archiver]
-        command.extend(['cr', output_fpath])
-        command.extend(map(str, sorted(objects)))
-
-        log_or_dot(logger, 'CreateObjectArchive running command: ' + ' '.join(command))
+        log_or_dot(logger, f"CreateObjectArchive running archiver for "
+                           f"'{output_fpath}'.")
         try:
-            run_command(command)
-        except Exception as err:
-            raise Exception(f"error creating object archive:\n{err}")
+            ar.create(output_fpath, sorted(objects))
+        except RuntimeError as err:
+            raise RuntimeError(f"error creating object archive:\n{err}") from err
 
         output_archives[root] = [output_fpath]

tests/unit_tests/steps/test_archive_objects.py

@@ -1,3 +1,12 @@
+##############################################################################
+# (c) Crown copyright Met Office. All rights reserved.
+# For further details please refer to the file COPYRIGHT
+# which you should have received as part of this distribution
+##############################################################################
+"""
+Test for the archive step.
+"""
+
 from unittest import mock
 from unittest.mock import call
 
@@ -9,22 +18,31 @@
 import pytest
 
 
-class Test_archive_objects(object):
+class TestArchiveObjects():
+    '''Test the achive step.
+    '''
 
     def test_for_exes(self):
-        # as used when archiving before linking exes
+        '''As used when archiving before linking exes.
+        '''
         targets = ['prog1', 'prog2']
 
         config = BuildConfig('proj', ToolBox())
-        config._artefact_store = {OBJECT_FILES: {target: [f'{target}.o', 'util.o'] for target in targets}}
+        config._artefact_store = {OBJECT_FILES: {target: [f'{target}.o', 'util.o']
+                                  for target in targets}}
 
-        with mock.patch('fab.steps.archive_objects.run_command') as mock_run_command, \
-             pytest.warns(UserWarning, match="_metric_send_conn not set, cannot send metrics"):
+        mock_result = mock.Mock(returncode=0, return_value=123)
+        with mock.patch('fab.newtools.tool.subprocess.run',
+                        return_value=mock_result) as mock_run_command, \
+                pytest.warns(UserWarning, match="_metric_send_conn not set, "
+                                                "cannot send metrics"):
             archive_objects(config=config)
 
         # ensure the correct command line calls were made
         expected_calls = [
-            call(['ar', 'cr', str(config.build_output / f'{target}.a'), f'{target}.o', 'util.o'])
+            call(['ar', 'cr', str(config.build_output / f'{target}.a'),
+                  f'{target}.o', 'util.o'],
+                 capture_output=True, env=None, cwd=None, check=False)
             for target in targets
         ]
         mock_run_command.assert_has_calls(expected_calls)
@@ -34,19 +52,23 @@ def test_for_exes(self):
             target: [str(config.build_output / f'{target}.a')] for target in targets}
 
     def test_for_library(self):
-        # as used when building an object archive or archiving before linking a shared library
-        pass
+        '''As used when building an object archive or archiving before linking
+        a shared library.
+        '''
 
         config = BuildConfig('proj', ToolBox())
         config._artefact_store = {OBJECT_FILES: {None: ['util1.o', 'util2.o']}}
 
-        with mock.patch('fab.steps.archive_objects.run_command') as mock_run_command, \
-             pytest.warns(UserWarning, match="_metric_send_conn not set, cannot send metrics"):
+        mock_result = mock.Mock(returncode=0, return_value=123)
+        with mock.patch('fab.newtools.tool.subprocess.run',
+                        return_value=mock_result) as mock_run_command, \
+                pytest.warns(UserWarning, match="_metric_send_conn not set, cannot send metrics"):
             archive_objects(config=config, output_fpath=config.build_output / 'mylib.a')
 
         # ensure the correct command line calls were made
         mock_run_command.assert_called_once_with([
-            'ar', 'cr', str(config.build_output / 'mylib.a'), 'util1.o', 'util2.o'])
+            'ar', 'cr', str(config.build_output / 'mylib.a'), 'util1.o', 'util2.o'],
+            capture_output=True, env=None, cwd=None, check=False)
 
         # ensure the correct artefacts were created
         assert config.artefact_store[OBJECT_ARCHIVES] == {