#421 Some EOL comments are not preserved

[Jacob Floyd]

These EOL comments disappear on round-trip (which I found while coming up with some tests for my ruamel.yaml-based re-formatter):

---
string_next_line: # EOL comment before string gets lost
  "this is a string bla bla
  more text"

# this is a comment
folded_block_scalar_with_octothorpe: > # > EOL comment gets lost
  # this is not a comment

# this is a comment
folded_chomp_strip_block_scalar_with_octothorpe: >- # > EOL comment gets lost
  # this is not a comment

# this is a comment
folded_chomp_keep_block_scalar_with_octothorpe: >+ # > EOL comment gets lost
  # this is not a comment

[Anthon van der Neut]

That first one is a known issue: you cannot have a comment between a key and its value.

The other three I can only explain as that I did forget folded scalar comment handling when I implemented the handling for literal scalar. I am not sure though if I push an extra release for that.

[Anthon van der Neut]

As I expected the last three only require minor changes, available in the handling of literal scalars with minor adjustments. They will be in 0.18 but if you can't wait it only affects two methods in emitter.py:

--- a/emitter.py
+++ b/emitter.py
@@ -874,7 +874,11 @@
         elif self.style == "'":
             self.write_single_quoted(self.analysis.scalar, split)
         elif self.style == '>':
-            self.write_folded(self.analysis.scalar)
+            try:
+                cmx = self.event.comment[1][0]
+            except (IndexError, TypeError):
+                cmx = ""
+            self.write_folded(self.analysis.scalar, cmx)
             if (
                 self.event.comment
                 and self.event.comment[0]
@@ -1440,9 +1444,11 @@
         hints += indicator
         return hints, indent, indicator

-    def write_folded(self, text: Any) -> None:
+    def write_folded(self, text: Any, comment: Any) -> None:
         hints, _indent, _indicator = self.determine_block_hints(text)
-        self.write_indicator('>' + hints, True)
+        if not isinstance(comment, str):
+            comment = ''
+        self.write_indicator('>' + hints + comment, True)
         if _indicator == '+':
             self.open_ended = True
         self.write_line_break()

[Anthon van der Neut]

See e.g. 418 for a duplicate of the first issue

[Anthon van der Neut]

The fix for folded scalars should be in 0.17.22+