cliutil: Take on --jobs support from audit_report.

conservancy_beancount/cliutil.py

@@ -59,6 +59,7 @@ from .beancount_types import (
 
 OutputFile = Union[int, IO]
 
+CPU_COUNT = len(os.sched_getaffinity(0))
 STDSTREAM_PATH = Path('-')
 VERSION = pkg_resources.require(PKGNAME)[0].version
 
@@ -241,6 +242,15 @@ class SearchTerm(NamedTuple):
             postings, self.meta_key, re.compile(self.pattern),
         )
 
+def add_jobs_argument(parser: argparse.ArgumentParser) -> argparse.Action:
+    return parser.add_argument(
+        '--jobs', '-j',
+        metavar='NUM',
+        type=jobs_arg,
+        default=CPU_COUNT,
+        help="""Maximum number of processes to run concurrently.
+Can specify a positive integer or a percentage of CPU cores. Default all cores.
+""")
 
 def add_loglevel_argument(parser: argparse.ArgumentParser,
                           default: LogLevel=LogLevel.INFO) -> argparse.Action:
@@ -306,6 +316,16 @@ def year_or_date_arg(arg: str) -> Union[int, datetime.date]:
     else:
         return date_arg(arg)
 
+def jobs_arg(arg: str) -> int:
+    if arg.endswith('%'):
+        arg_n = round(CPU_COUNT * 100 / int(arg[:-1]))
+    else:
+        arg_n = int(arg)
+    if arg_n < 1:
+        raise ValueError("--jobs argument must be a positive integer or percentage")
+    else:
+        return arg_n
+
 def make_entry_point(mod_name: str, prog_name: str=sys.argv[0]) -> Callable[[], int]:
     """Create an entry_point function for a tool
 

conservancy_beancount/tools/audit_report.py

@@ -52,17 +52,9 @@ from beancount.scripts import check as bc_check
 ArgList = List[str]
 ReportFunc = Callable[[ArgList, TextIO, TextIO, configmod.Config], int]
 
-CPU_COUNT = len(os.sched_getaffinity(0))
 PROGNAME = 'audit-report'
 logger = logging.getLogger('conservancy_beancount.tools.audit_report')
 
-def jobs_arg(arg: str) -> int:
-    if arg.endswith('%'):
-        arg_n = round(CPU_COUNT * 100 / int(arg[:-1]))
-    else:
-        arg_n = int(arg)
-    return max(1, arg_n)
-
 def parse_arguments(arglist: Optional[Sequence[str]]=None) -> argparse.Namespace:
     parser = argparse.ArgumentParser(prog=PROGNAME)
     cliutil.add_version_argument(parser)
@@ -72,14 +64,7 @@ def parse_arguments(arglist: Optional[Sequence[str]]=None) -> argparse.Namespace
         action='store_true',
         help="""Display progress information
 """)
-    parser.add_argument(
-        '--jobs', '-j',
-        metavar='NUM',
-        type=jobs_arg,
-        default=CPU_COUNT,
-        help="""Maximum number of processes to run concurrently.
-Can specify a positive integer or a percentage of CPU cores. Default all cores.
-""")
+    cliutil.add_jobs_argument(parser)
     parser.add_argument(
         '--output-directory', '-O',
         metavar='DIR',