Add option to pin packages considered unsafe in pip-compile

piptools/scripts/compile.py

@@ -53,10 +53,12 @@ class PipCommand(pip.basecommand.Command):
 @click.option('-o', '--output-file', nargs=1, type=str, default=None,
               help=('Output file name. Required if more than one input file is given. '
                     'Will be derived from input file otherwise.'))
+@click.option('--allow-unsafe', is_flag=True, default=False,
+              help="Pin packages considered unsafe: pip, setuptools & distribute")
 @click.argument('src_files', nargs=-1, type=click.Path(exists=True, allow_dash=True))
 def cli(verbose, dry_run, pre, rebuild, find_links, index_url, extra_index_url,
         client_cert, trusted_host, header, index, annotate, upgrade,
-        output_file, src_files):
+        output_file, allow_unsafe, src_files):
     """Compiles requirements.txt from requirements.in specs."""
     log.verbose = verbose
 
@@ -200,7 +202,8 @@ def cli(verbose, dry_run, pre, rebuild, find_links, index_url, extra_index_url,
                           default_index_url=repository.DEFAULT_INDEX_URL,
                           index_urls=repository.finder.index_urls,
                           trusted_hosts=pip_options.trusted_hosts,
-                          format_control=repository.finder.format_control)
+                          format_control=repository.finder.format_control,
+                          allow_unsafe=allow_unsafe)
     writer.write(results=results,
                  reverse_dependencies=reverse_dependencies,
                  primary_packages={key_from_req(ireq.req) for ireq in constraints})

piptools/writer.py

@@ -9,8 +9,9 @@
 
 
 class OutputWriter(object):
-    def __init__(self, src_files, dst_file, dry_run, emit_header, emit_index, annotate,
-                 default_index_url, index_urls, trusted_hosts, format_control):
+    def __init__(self, src_files, dst_file, dry_run, emit_header, emit_index,
+                 annotate, default_index_url, index_urls, trusted_hosts,
+                 format_control, allow_unsafe=False):
         self.src_files = src_files
         self.dst_file = dst_file
         self.dry_run = dry_run
@@ -21,6 +22,7 @@ def __init__(self, src_files, dst_file, dry_run, emit_header, emit_index, annota
         self.index_urls = index_urls
         self.trusted_hosts = trusted_hosts
         self.format_control = format_control
+        self.allow_unsafe = allow_unsafe
 
     def _sort_key(self, ireq):
         return (not ireq.editable, str(ireq.req).lower())
@@ -88,12 +90,16 @@ def _iter_lines(self, results, reverse_dependencies, primary_packages):
 
         if unsafe_packages:
             yield ''
-            yield comment('# The following packages are commented out because they are')
-            yield comment('# considered to be unsafe in a requirements file:')
+            yield comment('# The following packages are considered to be unsafe in a requirements file:')
 
             for ireq in unsafe_packages:
-                line = self._format_requirement(ireq, reverse_dependencies, primary_packages, include_specifier=False)
-                yield comment('# ' + line)
+                line = self._format_requirement(
+                    ireq, reverse_dependencies, primary_packages,
+                    include_specifier=self.allow_unsafe)
+                if self.allow_unsafe:
+                    yield line
+                else:
+                    yield comment('# ' + line)
 
     def write(self, results, reverse_dependencies, primary_packages):
         with ExitStack() as stack: