Check for blank line after shebang and grab actual comment block instead of hard-coded one

python/tidy/servo_tidy/licenseck.py

@@ -7,11 +7,6 @@
 # option. This file may not be copied, modified, or distributed
 # except according to those terms.
 
-# when wrapped to 80 chars, the longest license is 10 lines.
-# TODO actually grab whatever commented block is before the second blank line
-# of the file instead of hard-coding this.
-MAX_LICENSE_LINESPAN = 12
-
 MPL = """\
 This Source Code Form is subject to the terms of the Mozilla Public \
 License, v. 2.0. If a copy of the MPL was not distributed with this \

python/tidy/servo_tidy/tidy.py

@@ -163,13 +163,23 @@ def licensed_apache(header):
 def check_license(file_name, lines):
     if any(file_name.endswith(ext) for ext in (".toml", ".lock", ".json")):
         raise StopIteration
-    block = min(len(lines), licenseck.MAX_LICENSE_LINESPAN)
+
+    if lines[0].startswith("#!") and lines[1].strip():
+        yield (1, "missing blank line after shebang")
+
+    blank_lines = 0
+    max_blank_lines = 2 if lines[0].startswith("#!") else 1
     license_block = []
-    for l in lines[:block]:
+
+    for l in lines:
         l = l.rstrip('\n')
+        if not l.strip():
+            blank_lines += 1
+        if blank_lines >= max_blank_lines:
+            break
         line = uncomment(l)
         if line is not None:
-            license_block += [line]
+            license_block.append(line)
     contents = " ".join(license_block)
     valid_license = licensed_mpl(contents) or licensed_apache(contents)
     acknowledged_bad_license = "xfail-license" in contents

python/tidy/servo_tidy_tests/shebang_license.py

@@ -0,0 +1,4 @@
+#!/usr/bin/env python
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.

python/tidy/servo_tidy_tests/test_tidy.py

@@ -48,6 +48,11 @@ class CheckTidiness(unittest.TestCase):
         self.assertEqual('incorrect license', errors.next()[2])
         self.assertNoMoreErrors(errors)
 
+    def test_shebang_license(self):
+        errors = tidy.collect_errors_for_files(iterFile('shebang_license.py'), [], [tidy.check_license], print_text=False)
+        self.assertEqual('missing blank line after shebang', errors.next()[2])
+        self.assertNoMoreErrors(errors)
+
     def test_shell(self):
         errors = tidy.collect_errors_for_files(iterFile('shell_tidy.sh'), [], [tidy.check_shell], print_text=False)
         self.assertEqual('script does not have shebang "#!/usr/bin/env bash"', errors.next()[2])