| Q | A | ---------------- | ----- | Bug report? | yes | Feature request? | no | BC Break report? | no | RFC? | no | Symfony version | 3.4.4 Doing this: Yaml::dump( ["text" => " leading space in first line\nno leading space in last line\n"], 2, 4, Yaml::DUMP_MULTI_LINE_LITERAL_BLOCK ); Will produce this: text: | leading space in first line no leading space in last line Which is invalid YAML because when the first line has leading spaces it needs a [block indentation indicator](http://www.yaml.org/spec/1.2/spec.html#id2793979) like this: text: |4 leading space in first line no leading space in last line