Preserve line breaks in comments before test functions

This way line numbers match better in error messages.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/scripts/generate_test_code.py b/tests/scripts/generate_test_code.py
index c1d1c1c..b7c8e28 100755
--- a/tests/scripts/generate_test_code.py
+++ b/tests/scripts/generate_test_code.py
@@ -552,14 +552,12 @@
         pos = closing + 2
         # Replace inner comment by spaces. There needs to be at least one space
         # for things like 'int/*ihatespaces*/foo'. Go further and preserve the
-        # width of the comment, this way column positions in error messages
-        # remain correct.
-        # TODO: It would be better to preserve line breaks, to get accurate
-        # line numbers if there's something interesting after a comment on
-        # the same line.
+        # width of the comment and line breaks, this way positions in error
+        # messages remain correct.
         line = (line[:opening.start(0)] +
-                ' ' * (pos - opening.start(0)) +
+                re.sub(r'.', r' ', line[opening.start(0):pos]) +
                 line[pos:])
+    # Strip whitespace at the end of lines (it's irrelevant to error messages).
     return re.sub(r' +(\n|\Z)', r'\1', line)
 
 def parse_function_code(funcs_f, dependencies, suite_dependencies):