Potential fix for issue #4

 * workaround pallets/click#365
   by suclassing click.Command.main() to force the prog_name
   to self.name.
 * also refactored the usage display for
   pallets/click#393

src/scancode/cli.py

@@ -205,19 +205,29 @@ def print_version(ctx, param, value):
 '''
 
 
-short_help = '''Usage: scancode [OPTIONS] <input> <output_file>
+short_help = '''
 Try 'scancode --help' for help on options and arguments.'''
 
 
 formats = ['json', 'html', 'html-app']
 
 
 class ScanCommand(click.Command):
-    """
-    Workaround click 4.0 bug https://github.com/mitsuhiko/click/issues/365
-    """
     def get_usage(self, ctx):
-        return short_help
+        """
+        Ensure that usage points to the --help option explicitly.
+        Workaround click issue https://github.com/mitsuhiko/click/issues/393
+        """
+        return click.Command.get_usage(self, ctx) + short_help
+
+    def main(self, args=None, prog_name=None, complete_var=None,
+             standalone_mode=True, **extra):
+        """
+        Workaround click 4.0 bug https://github.com/mitsuhiko/click/issues/365
+        """
+        return click.Command.main(self, args=args, prog_name=self.name,
+                                  complete_var=complete_var,
+                                  standalone_mode=standalone_mode, **extra)
 
 
 @click.command(name='scancode', epilog=epilog_text, cls=ScanCommand)
@@ -240,7 +250,7 @@ def get_usage(self, ctx):
               help=('Show information about ScanCode and licensing and exit.'))
 @click.option('--version', is_flag=True, is_eager=True, callback=print_version,
               help=('Show the version and exit.'))
-def scancode(ctx, input, output_file, extract, copyright, license, format, verbose, *args, **kwargs):
+def scancode(ctx, input, output_file, extract, copyright, license, format, verbose, *args, **kwargs):  # @ReservedAssignment
     """scan the <input> file or directory for origin and license and save results to the <output_file>.
 
     The scan results are printed on terminal if <output_file> is not provided.
@@ -263,8 +273,8 @@ def scancode(ctx, input, output_file, extract, copyright, license, format, verbo
 
     # Default scan when no options is provided
     if not any(scans):
-        copyright = True
-        license = True
+        copyright = True  # @ReservedAssignment
+        license = True  # @ReservedAssignment
 
     if copyright or license:
         click.secho('Scanning files...', fg='green')
@@ -309,7 +319,7 @@ def scancode(ctx, input, output_file, extract, copyright, license, format, verbo
         click.secho('Scanning done.', fg='green')
 
 
-def scan_one(input_file, copyright, license, verbose=False):
+def scan_one(input_file, copyright, license, verbose=False):  # @ReservedAssignment
     """
     Scan one file and return scanned data.
     """
@@ -329,7 +339,7 @@ def scan_one(input_file, copyright, license, verbose=False):
     return data
 
 
-def extract_with_progress(input, verbose=False):
+def extract_with_progress(input, verbose=False):  # @ReservedAssignment
     """
     Extract archives and display progress.
     """

tests/scancode/test_cli.py

@@ -135,3 +135,19 @@ def test_scancode_skip_vcs_files_and_dirs_by_default(self):
         assert 1 == scan_result['count']
         scan_loc = as_posixpath(scan_result['results'][0]['location'])
         assert scan_loc.endswith('vcs.tgz/vcs/test.txt')
+
+    def test_usage_and_help_return_a_correct_script_name_on_all_platforms(self):
+        runner = CliRunner()
+        result = runner.invoke(cli.scancode, ['--help'])
+        assert 'Usage: scancode [OPTIONS]' in result.output
+        # this was showing up on Windows
+        assert 'scancode-script.py' not in result.output
+
+        result = runner.invoke(cli.scancode, [])
+        assert 'Usage: scancode [OPTIONS]' in result.output
+        # this was showing up on Windows
+        assert 'scancode-script.py' not in result.output
+
+        result = runner.invoke(cli.scancode, ['-xyz'])
+        # this was showing up on Windows
+        assert 'scancode-script.py' not in result.output