# YAML Test Matrix

--- &test-BF9H
  Title: Trailing comment in multiline plain scalar
  Tags: [ comment, error, scalar ]

YAML

---
plain: a
       b # end of scalar
       c

Expected Events

+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

Expected JSON



hs-reference-yeast

 invalid_incorrect
Line  Col Char Byte Token|Content
   1    0    0    0 +DOC |
   1    0    0    0 =HEAD|---
   1    3    3    3 +NODE|
   1    3    3    3 =EOL |\x0a
   2    0    4    4 +MAP |
   2    0    4    4 +PAIR|
   2    0    4    4 +NODE|
   2    0    4    4 +VAL |
   2    0    4    4 =TEXT|plain
   2    5    9    9 -VAL |
   2    5    9    9 -NODE|
   2    5    9    9 =SYNX|:
   2    6   10   10 =WSPC|.
   2    7   11   11 +NODE|
   2    7   11   11 +VAL |
   2    7   11   11 =TEXT|a
   2    8   12   12 =FOLD|\x0a
   3    0   13   13 =DENT|.
   3    1   14   14 =WSPC|......
   3    7   20   20 =TEXT|b
   3    8   21   21 -VAL |
   3    8   21   21 -NODE|
   3    8   21   21 =WSPC|.
   3    9   22   22 +COMM|
   3    9   22   22 =SYNX|#
   3   10   23   23 =META|.end.of.scalar
   3   24   37   37 -COMM|
   3   24   37   37 =EOL |\x0a
   4    0   38   38 -PAIR|
   4    0   38   38 -MAP |
   4    0   38   38 -NODE|
   4    0   38   38 -DOC |
   4    0   38   38 =ERR |Unexpected.'.'

raku-yamlish-json

 invalid_incorrect
{ "plain" : "a b  c" }

raku-yamlish-raku

 invalid_incorrect
{
  plain => "a b  c".Str,
}

c-libfyaml-event

 invalid_correct
stdin:4:8: error: invalid value after mapping
       c
       ^
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

c-libfyaml-json

 invalid_correct
stdin:4:8: error: invalid value after mapping
       c
       ^

c-libyaml-event

 invalid_correct
Parse error: did not find expected key
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

cpp-rapidyaml-event

 invalid_correct
-:4:1: (38B): ERROR: parse error - indentation should not increase at this point
-:4:1:        c  (size=8)
       ^~~~~~~~  (cols 1-9)

cpp-yamlcpp-event

 invalid_correct
Exception:
yaml-cpp: error at line 4, column 8: end of map not found
+STR
+DOC
+MAP
=VAL :plain
=VAL :a b

dotnet-yamldotnet-event

 invalid_correct
Unhandled exception. YamlDotNet.Core.SemanticErrorException: (Line: 4, Col: 8, Idx: 45) - (Line: 4, Col: 9, Idx: 46): While parsing a block mapping, did not find expected key.
   at YamlDotNet.Core.Parser.ParseBlockMappingKey(Boolean isFirst)
   at YamlDotNet.Core.Parser.StateMachine()
   at YamlDotNet.Core.Parser.MoveNext()
   at YamlDotNet.RepresentationModel.LibYamlEventStream.WriteTo(TextWriter textWriter)
   at Program.Main(String[] commandLineArguments)
Aborted (core dumped)
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

dotnet-yamldotnet-json

 invalid_correct
Unhandled exception. YamlDotNet.Core.SemanticErrorException: (Line: 4, Col: 8, Idx: 45) - (Line: 4, Col: 9, Idx: 46): While parsing a block mapping, did not find expected key.
   at YamlDotNet.Core.Parser.ParseBlockMappingKey(Boolean isFirst)
   at YamlDotNet.Core.Parser.StateMachine()
   at YamlDotNet.Core.Parser.MoveNext()
   at YamlDotNet.Core.ParserExtensions.TryConsume[T](IParser parser, T& event)
   at YamlDotNet.Serialization.NodeDeserializers.ScalarNodeDeserializer.YamlDotNet.Serialization.INodeDeserializer.Deserialize(IParser parser, Type expectedType, Func`3 nestedObjectDeserializer, Object& value)
   at YamlDotNet.Serialization.ValueDeserializers.NodeValueDeserializer.DeserializeValue(IParser parser, Type expectedType, SerializerState state, IValueDeserializer nestedObjectDeserializer)
   at YamlDotNet.Serialization.ValueDeserializers.AliasValueDeserializer.DeserializeValue(IParser parser, Type expectedType, SerializerState state, IValueDeserializer nestedObjectDeserializer)
   at YamlDotNet.Serialization.ValueDeserializers.NodeValueDeserializer.<>c__DisplayClass3_0.<DeserializeValue>b__0(IParser r, Type t)
   at YamlDotNet.Serialization.NodeDeserializers.DictionaryNodeDeserializer.DeserializeHelper(Type tKey, Type tValue, IParser parser, Func`3 nestedObjectDeserializer, IDictionary result)
   at YamlDotNet.Serialization.NodeDeserializers.DictionaryNodeDeserializer.YamlDotNet.Serialization.INodeDeserializer.Deserialize(IParser parser, Type expectedType, Func`3 nestedObjectDeserializer, Object& value)
   at YamlDotNet.Serialization.ValueDeserializers.NodeValueDeserializer.DeserializeValue(IParser parser, Type expectedType, SerializerState state, IValueDeserializer nestedObjectDeserializer)
   at YamlDotNet.Serialization.ValueDeserializers.AliasValueDeserializer.DeserializeValue(IParser parser, Type expectedType, SerializerState state, IValueDeserializer nestedObjectDeserializer)
   at YamlDotNet.Serialization.Deserializer.Deserialize(IParser parser, Type type)
   at YamlDotNet.Serialization.Deserializer.Deserialize(TextReader input, Type type)
   at YamlDotNet.Serialization.Deserializer.Deserialize(TextReader input)
   at Program.Main(String[] commandLineArguments)
Aborted (core dumped)

go-yaml-json

 invalid_correct
yaml: line 3: did not find expected key

hs-hsyaml-event

 invalid_correct
Parsing error near byte offset Pos {posByteOffset = 38, posCharOffset = 38, posLine = 4, posColumn = 0} (Unexpected ' ')
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b
-MAP
-DOC

hs-hsyaml-json

 invalid_correct
hsyaml-parser: user error (Unexpected ' ')

java-snakeengine-event

 invalid_correct
Exception in thread "main" while parsing a block mapping
 in reader, line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
 in reader, line 4, column 8:
           c
           ^

	at org.snakeyaml.engine.v2.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:689)
	at org.snakeyaml.engine.v2.parser.ParserImpl.lambda$produce$0(ParserImpl.java:185)
	at java.util.Optional.ifPresent(Optional.java:159)
	at org.snakeyaml.engine.v2.parser.ParserImpl.produce(ParserImpl.java:185)
	at org.snakeyaml.engine.v2.parser.ParserImpl.hasNext(ParserImpl.java:210)
	at org.yaml.editor.SnakeEngine2Events.yamlToEvents(SnakeEngine2Events.java:15)
	at org.yaml.editor.SnakeEngine2Events.main(SnakeEngine2Events.java:23)

java-snakeengine-json

 invalid_correct
Exception in thread "main" while parsing a block mapping
 in 'reader', line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
 in 'reader', line 4, column 8:
           c
           ^

	at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:660)
	at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:166)
	at org.yaml.snakeyaml.comments.CommentEventsCollector$1.peek(CommentEventsCollector.java:59)
	at org.yaml.snakeyaml.comments.CommentEventsCollector$1.peek(CommentEventsCollector.java:45)
	at org.yaml.snakeyaml.comments.CommentEventsCollector.collectEvents(CommentEventsCollector.java:140)
	at org.yaml.snakeyaml.comments.CommentEventsCollector.collectEvents(CommentEventsCollector.java:119)
	at org.yaml.snakeyaml.composer.Composer.composeScalarNode(Composer.java:217)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:187)
	at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:317)
	at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:308)
	at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:289)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:191)
	at org.yaml.snakeyaml.composer.Composer.getNode(Composer.java:116)
	at org.yaml.snakeyaml.constructor.BaseConstructor.getData(BaseConstructor.java:135)
	at org.yaml.snakeyaml.Yaml$1.next(Yaml.java:514)
	at org.yaml.editor.Snake2Json.yamlToJson(Snake2Json.java:20)
	at org.yaml.editor.Snake2Json.main(Snake2Json.java:27)

java-snakeyaml-event

 invalid_correct
Exception in thread "main" while parsing a block mapping
 in 'reader', line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
 in 'reader', line 4, column 8:
           c
           ^

	at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:660)
	at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:166)
	at org.yaml.snakeyaml.Yaml$3.hasNext(Yaml.java:677)
	at org.yaml.editor.Snake2Events.yamlToEvents(Snake2Events.java:134)
	at org.yaml.editor.Snake2Events.main(Snake2Events.java:142)

java-snakeyaml-json

 invalid_correct
Exception in thread "main" while parsing a block mapping
 in 'reader', line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
 in 'reader', line 4, column 8:
           c
           ^

	at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:660)
	at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:166)
	at org.yaml.snakeyaml.comments.CommentEventsCollector$1.peek(CommentEventsCollector.java:59)
	at org.yaml.snakeyaml.comments.CommentEventsCollector$1.peek(CommentEventsCollector.java:45)
	at org.yaml.snakeyaml.comments.CommentEventsCollector.collectEvents(CommentEventsCollector.java:140)
	at org.yaml.snakeyaml.comments.CommentEventsCollector.collectEvents(CommentEventsCollector.java:119)
	at org.yaml.snakeyaml.composer.Composer.composeScalarNode(Composer.java:217)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:187)
	at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:317)
	at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:308)
	at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:289)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:191)
	at org.yaml.snakeyaml.composer.Composer.getNode(Composer.java:116)
	at org.yaml.snakeyaml.constructor.BaseConstructor.getData(BaseConstructor.java:135)
	at org.yaml.snakeyaml.Yaml$1.next(Yaml.java:514)
	at org.yaml.editor.Snake2Json.yamlToJson(Snake2Json.java:20)
	at org.yaml.editor.Snake2Json.main(Snake2Json.java:27)

js-jsyaml-json

 invalid_correct
/node/node_modules/js-yaml/lib/loader.js:187
  throw generateError(state, message);
  ^
YAMLException: bad indentation of a mapping entry (4:8)

 1 | ---
 2 | plain: a
 3 |        b # end of scalar
 4 |        c
------------^
    at generateError (/node/node_modules/js-yaml/lib/loader.js:183:10)
    at throwError (/node/node_modules/js-yaml/lib/loader.js:187:9)
    at readBlockMapping (/node/node_modules/js-yaml/lib/loader.js:1182:7)
    at composeNode (/node/node_modules/js-yaml/lib/loader.js:1441:12)
    at readDocument (/node/node_modules/js-yaml/lib/loader.js:1625:3)
    at loadDocuments (/node/node_modules/js-yaml/lib/loader.js:1688:5)
    at Object.loadAll (/node/node_modules/js-yaml/lib/loader.js:1701:19)
    at Object.<anonymous> (/yaml/bin/js-jsyaml-json:7:13)
    at Module._compile (internal/modules/cjs/loader.js:778:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)

js-yaml-event

 invalid_correct
All mapping items must start at the same column at line 4, column 1:

       b # end of scalar
       c
^
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

js-yaml-json

 invalid_correct
/yaml/bin/js-yaml-json:8
  if (doc.errors.length !== 0) throw doc.errors[0]
                               ^

YAMLParseError: All mapping items must start at the same column at line 4, column 1:

       b # end of scalar
       c
^

    at Composer.onError (/node/node_modules/yaml/dist/compose/composer.js:71:34)
    at Object.resolveBlockMap (/node/node_modules/yaml/dist/compose/resolve-block-map.js:33:21)
    at Object.composeCollection (/node/node_modules/yaml/dist/compose/compose-collection.js:13:36)
    at Object.composeNode (/node/node_modules/yaml/dist/compose/compose-node.js:30:38)
    at Object.composeDoc (/node/node_modules/yaml/dist/compose/compose-doc.js:32:23)
    at Composer.next (/node/node_modules/yaml/dist/compose/composer.js:152:40)
    at next (<anonymous>)
    at Composer.compose (/node/node_modules/yaml/dist/compose/composer.js:134:25)
    at compose.next (<anonymous>)
    at Function.from (<anonymous>)

lua-lyaml-json

 invalid_correct
luajit: 2:8: did not find expected key
stack traceback:
	[C]: in function 'error'
	/usr/local/share/lua/5.1/lyaml/init.lua:306: in function 'error'
	/usr/local/share/lua/5.1/lyaml/init.lua:325: in function 'parse'
	/usr/local/share/lua/5.1/lyaml/init.lua:443: in function 'load_node'
	/usr/local/share/lua/5.1/lyaml/init.lua:340: in function 'load_node'
	/usr/local/share/lua/5.1/lyaml/init.lua:497: in function 'load'
	/yaml/bin/lua-lyaml-json:6: in main chunk
	[C]: at 0x556e1bd76f97

nim-nimyaml-event

 invalid_correct
/tmp/NimYAML-0.16.0/yaml/stream.nim(134) nimyaml_event
/tmp/NimYAML-0.16.0/yaml/stream.nim(106) next
Error: unhandled exception: Invalid indentation: got 7, expected 0 [YamlStreamError]
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

perl-pp-event

 invalid_correct
Line      : 4
Column    : 8
Message   : Bad indendation in MAP
Where     : /perl5/lib/perl5/YAML/PP/Parser.pm line 204
YAML      : "c\n"
  at /yaml/bin/perl-pp-event line 25.
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

perl-pp-json

 invalid_correct
Line      : 4
Column    : 8
Message   : Bad indendation in MAP
Where     : /perl5/lib/perl5/YAML/PP/Parser.pm line 204
YAML      : "c\n"
  at /perl5/lib/perl5/YAML/PP/Loader.pm line 94.

perl-pp-perl

 invalid_correct
Line      : 4
Column    : 8
Message   : Bad indendation in MAP
Where     : /perl5/lib/perl5/YAML/PP/Parser.pm line 204
YAML      : "c\n"
  at /perl5/lib/perl5/YAML/PP/Loader.pm line 94.

perl-pplibyaml-json

 invalid_correct
YAML::PP::LibYAML Error: The problem:

    did not find expected key

was found at , line: 4, column: 8
while parsing a block mapping at line: 2, column: 1

perl-pplibyaml-perl

 invalid_correct
YAML::PP::LibYAML Error: The problem:

    did not find expected key

was found at , line: 4, column: 8
while parsing a block mapping at line: 2, column: 1

perl-refparser-event

 invalid_correct
Parser finished before end of input at /perl5/lib/perl5/YAML/Parser.pm line 4056, <> line 1.

perl-syck-json

 invalid_correct
Syck parser (line 4, column 7): syntax error at /perl5/lib/perl5/x86_64-linux-thread-multi/YAML/Syck.pm line 60, <> line 1.

perl-syck-perl

 invalid_correct
Syck parser (line 4, column 7): syntax error at /perl5/lib/perl5/x86_64-linux-thread-multi/YAML/Syck.pm line 60, <> line 1.

perl-tiny-json

 invalid_correct
YAML::Tiny found bad indenting in line '       b # end of scalar' at /yaml/bin/perl-tiny-json line 12.

perl-tiny-perl

 invalid_correct
YAML::Tiny found bad indenting in line '       b # end of scalar' at /yaml/bin/perl-tiny-perl line 15.

perl-xs-json

 invalid_correct
YAML::XS::Load Error: The problem:

    did not find expected key

was found at document: 1, line: 4, column: 8
while parsing a block mapping at line: 2, column: 1

perl-xs-perl

 invalid_correct
YAML::XS::Load Error: The problem:

    did not find expected key

was found at document: 1, line: 4, column: 8
while parsing a block mapping at line: 2, column: 1

perl-yaml-json

 invalid_correct
YAML Error: Inconsistent indentation level
   Code: YAML_PARSE_ERR_INCONSISTENT_INDENTATION
   Line: 3
   Document: 1
 at /perl5/lib/perl5/YAML/Loader.pm line 804.

perl-yaml-perl

 invalid_correct
YAML Error: Inconsistent indentation level
   Code: YAML_PARSE_ERR_INCONSISTENT_INDENTATION
   Line: 3
   Document: 1
 at /perl5/lib/perl5/YAML/Loader.pm line 804.

py-pyyaml-event

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-pyyaml-event", line 7, in <module>
    for event in yaml.parse(sys.stdin.read()):
  File "/python/lib/python3.7/site-packages/yaml/__init__.py", line 46, in parse
    while loader.check_event():
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 439, in parse_block_mapping_key
    "expected <block end>, but found %r" % token.id, token.start_mark)
yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

py-pyyaml-json

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-pyyaml-json", line 19, in <module>
    for doc in yaml.load_all(sys.stdin.read(), Loader=yaml.FullLoader):
  File "/python/lib/python3.7/site-packages/yaml/__init__.py", line 93, in load_all
    yield loader.get_data()
  File "/python/lib/python3.7/site-packages/yaml/constructor.py", line 45, in get_data
    return self.construct_document(self.get_node())
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 27, in get_node
    return self.compose_document()
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 55, in compose_document
    node = self.compose_node(None, None)
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 127, in compose_mapping_node
    while not self.check_event(MappingEndEvent):
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 439, in parse_block_mapping_key
    "expected <block end>, but found %r" % token.id, token.start_mark)
yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^

py-pyyaml-py

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-pyyaml-py", line 36, in <module>
    for doc in yaml.load_all(sys.stdin.read(), Loader=yaml.FullLoader):
  File "/python/lib/python3.7/site-packages/yaml/__init__.py", line 93, in load_all
    yield loader.get_data()
  File "/python/lib/python3.7/site-packages/yaml/constructor.py", line 45, in get_data
    return self.construct_document(self.get_node())
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 27, in get_node
    return self.compose_document()
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 55, in compose_document
    node = self.compose_node(None, None)
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
  File "/python/lib/python3.7/site-packages/yaml/composer.py", line 127, in compose_mapping_node
    while not self.check_event(MappingEndEvent):
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/yaml/parser.py", line 439, in parse_block_mapping_key
    "expected <block end>, but found %r" % token.id, token.start_mark)
yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^

py-ruamel-event

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-ruamel-event", line 7, in <module>
    for event in ruamel.yaml.parse(sys.stdin.read()):
  File "/python/lib/python3.7/site-packages/ruamel/yaml/main.py", line 1024, in parse
    while loader._parser.check_event():
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 146, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 616, in parse_block_mapping_key
    token.start_mark,
ruamel.yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^ (line: 2)
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^ (line: 4)
+STR
+DOC ---
+MAP
=VAL :plain
=VAL :a b

py-ruamel-json

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-ruamel-json", line 19, in <module>
    for doc in ruamel.yaml.load_all(sys.stdin.read(), Loader=ruamel.yaml.Loader):
  File "/python/lib/python3.7/site-packages/ruamel/yaml/main.py", line 1097, in load_all
    yield loader._constructor.get_data()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/constructor.py", line 114, in get_data
    return self.construct_document(self.composer.get_node())
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 66, in get_node
    return self.compose_document()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 99, in compose_document
    node = self.compose_node(None, None)
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 143, in compose_node
    node = self.compose_mapping_node(anchor)
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 216, in compose_mapping_node
    while not self.parser.check_event(MappingEndEvent):
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 146, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 616, in parse_block_mapping_key
    token.start_mark,
ruamel.yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^ (line: 2)
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^ (line: 4)

py-ruamel-py

 invalid_correct
Traceback (most recent call last):
  File "/yaml/bin/py-ruamel-py", line 36, in <module>
    for doc in ruamel.yaml.load_all(sys.stdin.read(), Loader=ruamel.yaml.Loader):
  File "/python/lib/python3.7/site-packages/ruamel/yaml/main.py", line 1097, in load_all
    yield loader._constructor.get_data()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/constructor.py", line 114, in get_data
    return self.construct_document(self.composer.get_node())
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 66, in get_node
    return self.compose_document()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 99, in compose_document
    node = self.compose_node(None, None)
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 143, in compose_node
    node = self.compose_mapping_node(anchor)
  File "/python/lib/python3.7/site-packages/ruamel/yaml/composer.py", line 216, in compose_mapping_node
    while not self.parser.check_event(MappingEndEvent):
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 146, in check_event
    self.current_event = self.state()
  File "/python/lib/python3.7/site-packages/ruamel/yaml/parser.py", line 616, in parse_block_mapping_key
    token.start_mark,
ruamel.yaml.parser.ParserError: while parsing a block mapping
  in "<unicode string>", line 2, column 1:
    plain: a
    ^ (line: 2)
expected <block end>, but found '<scalar>'
  in "<unicode string>", line 4, column 8:
           c
           ^ (line: 4)

ruby-psych-json

 invalid_correct
/ruby/gems/psych/lib/psych.rb:459:in `parse': (<unknown>): did not find expected key while parsing a block mapping at line 2 column 1 (Psych::SyntaxError)
	from /ruby/gems/psych/lib/psych.rb:459:in `parse_stream'
	from /ruby/gems/psych/lib/psych.rb:565:in `load_stream'
	from /yaml/bin/ruby-psych-json:6:in `<main>'

rust-yamlrust-event

 invalid_correct
Error: ScanError { mark: Marker { index: 45, line: 4, col: 7 }, info: "while parsing a block mapping, did not find expected key" }
+STR
+DOC
+MAP
=VAL :plain
=VAL :a b