add click option for --safety-ignore instead of parsing it out of args

pipenv/cli.py

@@ -694,6 +694,12 @@ def run(command, args, three=None, python=False):
     default=False,
     help="Given a code path, show potentially unused dependencies.",
 )
+@option(
+    '--safety-ignore',
+    is_flag=True,
+    default=False,
+    help="Ignore specified packages when doing the safety check"
+)
 @argument('args', nargs=-1)
 def check(
     three=None,
@@ -701,12 +707,18 @@ def check(
     system=False,
     unused=False,
     style=False,
+    safety_ignore=False,
     args=None,
 ):
     from .core import do_check
-
+    print(safety_ignore)
     do_check(
-        three=three, python=python, system=system, unused=unused, args=args
+        three=three,
+        python=python,
+        system=system,
+        unused=unused,
+        safety_ignore=safety_ignore,
+        args=args
     )
 
 

pipenv/core.py

@@ -2338,7 +2338,7 @@ def do_run(command, args, three=None, python=False):
         do_run_posix(script, command=command)
 
 
-def do_check(three=None, python=False, system=False, unused=False, args=None):
+def do_check(three=None, python=False, system=False, unused=False, safety_ignore=False,args=None):
     if not system:
         # Ensure that virtualenv is available.
         ensure_project(three=three, python=python, validate=False, warn=False)
@@ -2409,12 +2409,9 @@ def do_check(three=None, python=False, system=False, unused=False, args=None):
         python = which('python')
     else:
         python = system_which('python')
-    try:
-        if '--safety-ignore' in args[0]:
-            ignore = '-i ' + ' -i'.join(args[1:])
-        else:
-            ignore = ''
-    except IndexError:
+    if safety_ignore:
+        ignore = '-i ' + ' -i '.join(args)
+    else:
         ignore = ''
     c = delegator.run(
         '"{0}" {1} check --json --key=1ab8d58f-5122e025-83674263-bc1e79e0 {2}'.format(