# YAML Test Matrix

--- &test-2JQS
  Title: Block Mapping with Missing Keys
  Tags: [ duplicate-key, empty-key, mapping ]

YAML

: a
: b

Expected Events

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

Expected JSON



c-libfyaml-event

 ok

cpp-rapidyaml-event

 ok

cpp-yamlcpp-event

 ok

dotnet-yamldotnet-event

 ok

hs-hsyaml-event

 ok

nim-nimyaml-event

 ok

perl-pp-event

 ok

perl-refparser-event

 ok

py-ruamel-event

 ok

rust-yamlrust-event

 ok

perl-pp-perl

 error
Duplicate key '' at /perl5/lib/perl5/YAML/PP/Parser.pm line 61.
 at /perl5/lib/perl5/YAML/PP/Loader.pm line 94.

perl-syck-perl

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

py-ruamel-py

 error
Traceback (most recent call last):
  File "/yaml/bin/py-ruamel-py", line 38, in <module>
    for doc in yaml.load_all(sys.stdin.read()):
  File "/python/lib/python3.12/site-packages/ruamel/yaml/main.py", line 476, in load_all
    yield constructor.get_data()
          ^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 110, in get_data
    return self.construct_document(self.composer.get_node())
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 125, in construct_document
    for _dummy in generator:
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 633, in construct_yaml_map
    value = self.construct_mapping(node)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 429, in construct_mapping
    return BaseConstructor.construct_mapping(self, node, deep=deep)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 246, in construct_mapping
    if self.check_mapping_key(node, key_node, mapping, key, value):
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 278, in check_mapping_key
    raise DuplicateKeyError(*args)
ruamel.yaml.constructor.DuplicateKeyError: while constructing a mapping
  in "<unicode string>", line 1, column 1:
    : a
    ^ (line: 1)
found duplicate key "None" with value "b" (original value: "a")
  in "<unicode string>", line 2, column 1:
    : b
    ^ (line: 2)

To suppress this check see:
    http://yaml.readthedocs.io/en/latest/api.html#duplicate-keys

c-libfyaml-json

 na


 

dotnet-yamldotnet-json

 na
Unhandled exception. YamlDotNet.Core.YamlException: (Line: 1, Col: 1, Idx: 0) - (Line: 1, Col: 1, Idx: 0): Exception during deserialization
 ---> System.ArgumentNullException: Value cannot be null. (Parameter 'key')
   at System.Collections.Generic.Dictionary`2.System.Collections.IDictionary.set_Item(Object key, Object value)
   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)
   --- End of inner exception stack trace ---
   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

 na
yaml: did not find expected key

hs-hsyaml-json

 na
{"":"b"}

hs-reference-yeast

 na
Line  Col Char Byte Token|Content
   1    0    0    0 +DOC |
   1    0    0    0 +NODE|
   1    0    0    0 +MAP |
   1    0    0    0 +PAIR|
   1    0    0    0 +NODE|
   1    0    0    0 +VAL |
   1    0    0    0 -VAL |
   1    0    0    0 -NODE|
   1    0    0    0 =SYNX|:
   1    1    1    1 =WSPC|.
   1    2    2    2 +NODE|
   1    2    2    2 +VAL |
   1    2    2    2 =TEXT|a
   1    3    3    3 -VAL |
   1    3    3    3 -NODE|
   1    3    3    3 =EOL |\x0a
   2    0    4    4 -PAIR|
   2    0    4    4 +PAIR|
   2    0    4    4 +NODE|
   2    0    4    4 +VAL |
   2    0    4    4 -VAL |
   2    0    4    4 -NODE|
   2    0    4    4 =SYNX|:
   2    1    5    5 =WSPC|.
   2    2    6    6 +NODE|
   2    2    6    6 +VAL |
   2    2    6    6 =TEXT|b
   2    3    7    7 -VAL |
   2    3    7    7 -NODE|
   2    3    7    7 =EOL |\x0a
   3    0    8    8 -PAIR|
   3    0    8    8 -MAP |
   3    0    8    8 -NODE|
   3    0    8    8 -DOC |

js-jsyaml-json

 na
/node/node_modules/js-yaml/lib/loader.js:187
  throw generateError(state, message);
  ^
YAMLException: incomplete explicit mapping pair; a key node is missed; or followed by a non-tabulated empty line (1:1)

 1 | : a
-----^
 2 | : b
    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:1090:9)
    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 (node:internal/modules/cjs/loader:1358:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1416:10) {
  reason: 'incomplete explicit mapping pair; a key node is missed; or followed by a non-tabulated empty line',
  mark: {
    name: null,
    buffer: ': a\n: b\n',
    position: 0,
    line: 0,
    column: 0,
    snippet: ' 1 | : a\n-----^\n 2 | : b'
  }
}

Node.js v20.13.1

js-yaml-json

 na
/yaml/bin/js-yaml-json:9
    if (doc.errors.length !== 0) throw doc.errors[0]
                                 ^

YAMLParseError: Map keys must be unique at line 2, column 1:

: a
: b
^

    at Composer.onError (/node/node_modules/yaml/dist/compose/composer.js:69:34)
    at Object.resolveBlockMap (/node/node_modules/yaml/dist/compose/resolve-block-map.js:62:13)
    at resolveCollection (/node/node_modules/yaml/dist/compose/compose-collection.js:13:27)
    at Object.composeCollection (/node/node_modules/yaml/dist/compose/compose-collection.js:47:16)
    at Object.composeNode (/node/node_modules/yaml/dist/compose/compose-node.js:31:38)
    at Object.composeDoc (/node/node_modules/yaml/dist/compose/compose-doc.js:34:23)
    at Composer.next (/node/node_modules/yaml/dist/compose/composer.js:149:40)
    at next (<anonymous>)
    at Composer.compose (/node/node_modules/yaml/dist/compose/composer.js:131:25)
    at compose.next (<anonymous>) {
  code: 'DUPLICATE_KEY',
  pos: [ 4, 5 ],
  linePos: [ { line: 2, col: 1 }, { line: 2, col: 2 } ]
}

Node.js v20.13.1

lua-lyaml-json

 na
luajit: 1:1: 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 0x563b52e82ed0

perl-pp-json

 na
Duplicate key '' at /perl5/lib/perl5/YAML/PP/Parser.pm line 61.
 at /perl5/lib/perl5/YAML/PP/Loader.pm line 94.

perl-pplibyaml-json

 na
YAML::PP::LibYAML Error: The problem:

    did not find expected key

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

perl-syck-json

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

perl-tiny-json

 na
YAML::Tiny failed to classify line ': a' at /yaml/bin/perl-tiny-json line 12.

perl-xs-json

 na
YAML::XS::Load Error: The problem:

    did not find expected key

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

perl-yaml-json

 na
{
   "" : "a"
}

perl-yaml-perl

 na
{
  '' => 'a'
}

py-pyyaml-json

 na
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/python3.12/site-packages/yaml/__init__.py", line 130, in load_all
    yield loader.get_data()
          ^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/constructor.py", line 45, in get_data
    return self.construct_document(self.get_node())
                                   ^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 27, in get_node
    return self.compose_document()
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 55, in compose_document
    node = self.compose_node(None, None)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 127, in compose_mapping_node
    while not self.check_event(MappingEndEvent):
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
                         ^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 425, in parse_block_mapping_first_key
    return self.parse_block_mapping_key()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 438, in parse_block_mapping_key
    raise ParserError("while parsing a block mapping", self.marks[-1],
yaml.parser.ParserError: while parsing a block mapping
expected <block end>, but found ':'
  in "<unicode string>", line 1, column 1:
    : a
    ^

py-ruamel-json

 na
Traceback (most recent call last):
  File "/yaml/bin/py-ruamel-json", line 21, in <module>
    for doc in yaml.load_all(sys.stdin.read()):
  File "/python/lib/python3.12/site-packages/ruamel/yaml/main.py", line 476, in load_all
    yield constructor.get_data()
          ^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 110, in get_data
    return self.construct_document(self.composer.get_node())
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 125, in construct_document
    for _dummy in generator:
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 633, in construct_yaml_map
    value = self.construct_mapping(node)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 429, in construct_mapping
    return BaseConstructor.construct_mapping(self, node, deep=deep)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 246, in construct_mapping
    if self.check_mapping_key(node, key_node, mapping, key, value):
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/ruamel/yaml/constructor.py", line 278, in check_mapping_key
    raise DuplicateKeyError(*args)
ruamel.yaml.constructor.DuplicateKeyError: while constructing a mapping
  in "<unicode string>", line 1, column 1:
    : a
    ^ (line: 1)
found duplicate key "None" with value "b" (original value: "a")
  in "<unicode string>", line 2, column 1:
    : b
    ^ (line: 2)

To suppress this check see:
    http://yaml.readthedocs.io/en/latest/api.html#duplicate-keys

ruby-psych-json

 na
/ruby/gems/psych/lib/psych.rb:458:in `parse': (<unknown>): did not find expected key while parsing a block mapping at line 1 column 1 (Psych::SyntaxError)
	from /ruby/gems/psych/lib/psych.rb:458:in `parse_stream'
	from /ruby/gems/psych/lib/psych.rb:632:in `load_stream'
	from /yaml/bin/ruby-psych-json:6:in `<main>'

c-libyaml-event

 ni
+STR
+DOC
+MAP
Parse error: did not find expected key

js-yaml-event

 ni
+STR
+DOC
+MAP
=VAL :
=VAL :a
Map keys must be unique at line 2, column 1:

: a
: b
^

perl-pplibyaml-perl

 ni
YAML::PP::LibYAML Error: The problem:

    did not find expected key

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

perl-tiny-perl

 ni
YAML::Tiny failed to classify line ': a' at /yaml/bin/perl-tiny-perl line 15.

perl-xs-perl

 ni
YAML::XS::Load Error: The problem:

    did not find expected key

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

py-pyyaml-event

 ni
+STR
+DOC
+MAP
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/python3.12/site-packages/yaml/__init__.py", line 75, in parse
    while loader.check_event():
          ^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
                         ^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 425, in parse_block_mapping_first_key
    return self.parse_block_mapping_key()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 438, in parse_block_mapping_key
    raise ParserError("while parsing a block mapping", self.marks[-1],
yaml.parser.ParserError: while parsing a block mapping
expected <block end>, but found ':'
  in "<unicode string>", line 1, column 1:
    : a
    ^

py-pyyaml-py

 ni
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/python3.12/site-packages/yaml/__init__.py", line 130, in load_all
    yield loader.get_data()
          ^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/constructor.py", line 45, in get_data
    return self.construct_document(self.get_node())
                                   ^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 27, in get_node
    return self.compose_document()
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 55, in compose_document
    node = self.compose_node(None, None)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/composer.py", line 127, in compose_mapping_node
    while not self.check_event(MappingEndEvent):
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
                         ^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 425, in parse_block_mapping_first_key
    return self.parse_block_mapping_key()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/python/lib/python3.12/site-packages/yaml/parser.py", line 438, in parse_block_mapping_key
    raise ParserError("while parsing a block mapping", self.marks[-1],
yaml.parser.ParserError: while parsing a block mapping
expected <block end>, but found ':'
  in "<unicode string>", line 1, column 1:
    : a
    ^