correctly handle whitespace-only lines

Author: boegel

easybuild/framework/easyconfig/format/one.py

@@ -391,7 +391,7 @@ def grab_more_comment_lines(lines, param_key):
                 line = lines.pop(0)
                 _, actual_comment = split_on_comment_hash(line, param_key)
                 # prefix comment with '#' unless line was empty
-                if line:
+                if line.strip():
                     actual_comment = '# ' + actual_comment
                 comment_lines.append(actual_comment.strip())
 

test/framework/easyconfig.py

@@ -1900,7 +1900,7 @@ def test_dump_comments(self):
             "#",
             "# which may include empty comment lines",
             "    # weirdly indented lines",
-            '',
+            '  ',  # whitespace-only line, should get stripped (but no # added)
             "# or flat out empty lines",
             '',
             "easyblock = 'ConfigureMake'",