script-docs.py: add support for printing errors in GitHub actions format

travis/lint.py

@@ -105,7 +105,7 @@ class TabLinter(Linter):
 linters = [cls() for cls in Linter.__subclasses__() if not cls.ignore]
 
 def main():
-    is_github_actions = os.environ.get('GITHUB_ACTIONS')
+    is_github_actions = bool(os.environ.get('GITHUB_ACTIONS'))
     root_path = os.path.abspath(sys.argv[1] if len(sys.argv) > 1 else '.')
     if not os.path.exists(root_path):
         print('Nonexistent path: %s' % root_path)

travis/script-docs.py

@@ -1,11 +1,10 @@
 #!/usr/bin/env python3
-from __future__ import print_function
-from io import open
 import os
 from os.path import basename, dirname, join, splitext
 import sys
 
 SCRIPT_PATH = sys.argv[1] if len(sys.argv) > 1 else 'scripts'
+IS_GITHUB_ACTIONS = bool(os.environ.get('GITHUB_ACTIONS'))
 
 def expected_cmd(path):
     """Get the command from the name of a script."""
@@ -20,42 +19,61 @@ def check_ls(fname, line):
     line = line.strip()
     comment = '--' if fname.endswith('.lua') else '#'
     if '[====[' in line or not line.startswith(comment):
-        print('Error: no leading comment in ' + fname)
+        print_error('missing leading comment (requred for `ls`)', fname)
         return 1
     return 0
 
 
+def print_error(message, filename, line=None):
+    if not isinstance(line, int):
+        line = 1
+    print('Error: %s:%i: %s' % (filename, line, message))
+    if IS_GITHUB_ACTIONS:
+        print('::error file=%s,line=%i::%s' % (filename, line, message))
+
+
 def check_file(fname):
     errors, doclines = 0, []
     tok1, tok2 = ('=begin', '=end') if fname.endswith('.rb') else \
         ('[====[', ']====]')
+    doc_start_line = None
     with open(fname, errors='ignore') as f:
         lines = f.readlines()
+        if not lines:
+            print_error('empty file', fname)
+            return 1
         errors += check_ls(fname, lines[0])
-        for l in lines:
+        for i, l in enumerate(lines):
             if doclines or l.strip().endswith(tok1):
+                if not doclines:
+                    doc_start_line = i + 1
                 doclines.append(l.rstrip())
             if l.startswith(tok2):
                 break
         else:
             if doclines:
-                print('Error: docs start but not end: ' + fname)
+                print_error('docs start but do not end', fname, doc_start_line)
             else:
-                print('Error: no documentation in: ' + fname)
+                print_error('no documentation found', fname)
             return 1
 
     if not doclines:
-        print('Error: missing or malformed documentation in: ' + fname)
+        print_error('missing or malformed documentation', fname)
         return 1
 
     title, underline = [d for d in doclines
                         if d and '=begin' not in d and '[====[' not in d][:2]
-    if underline != '=' * len(title):
-        print('Error: title/underline mismatch:', fname, title, underline)
+    title_line = doc_start_line + doclines.index(title)
+    expected_underline = '=' * len(title)
+    if underline != expected_underline:
+        print_error('title/underline mismatch: expected {!r}, got {!r}'.format(
+                expected_underline, underline),
+            fname, title_line + 1)
         errors += 1
     if title != expected_cmd(fname):
-        print('Warning: expected script title {}, got {}'.format(
-              expected_cmd(fname), title))
+        print_error('expected script title {!r}, got {!r}'.format(
+                expected_cmd(fname), title),
+            fname, title_line)
         errors += 1
     return errors