I have the following code that update the yaml content:

final editor = YamlEditor(mppm.toString());
  editor.appendToList(['packages'], "*");
  print(editor);

Output is:

{name: mppm, packages: [packages/*, "*"]}

But I am curious how can I add this content back to the yaml file?

If I use the following code to update the yaml file. It just add it as a normal string without any proper formatting:

File("pubspec-output.yaml").writeAsStringSync(editor.toString());

Bumps actions/checkout from 3.1.0 to 3.2.0.

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

See this example:

import 'package:yaml_edit/yaml_edit.dart';

void main() {
  final yamlEditor = YamlEditor('''
analyzer:
  a:
    b: true
''');
  yamlEditor.update(['analyzer', 'language'], {'strict-casts': true});
  var lines = yamlEditor.toString().split('\n');
  print(lines.map((l) => "'$l'").join('\n'));
}

This results in this output, note the trailing space after language::

'analyzer:'
'  a:'
'    b: true'
'  language: '
'    strict-casts: true'
''

in the readme.md

import 'package:yaml_edit/yaml_edit.dart';

void main() {
  final yamlEditor = YamlEditor('{YAML: YAML}');
  yamlEditor.assign(['YAML'], "YAML Ain't Markup Language");
  print(yamlEditor);
  // Expected output:
  // {YAML: YAML Ain't Markup Language}
}

https://github.com/dart-lang/yaml_edit/blob/0ae689745e5796e12d77f93f7c2b2bfff7310489/README.md?plain=1#L14 but YamlEditor does not contains this method

This probably needs some test cases, and I'm sure the code can be improved further!

void main() {
  final doc = YamlEditor('');
  doc.update(
      [],
      wrapAsCustomStyledYamlNode({
        'title': 'Short string as title',
        'description': [
          'Multiple lines with losts of text',
          'that you really makes you want',
          'the YAML to be written with literal strings',
        ].join('\n'),
      }));
  print(doc.toString());
}

YamlNode wrapAsCustomStyledYamlNode(
  Object? value, {
  CollectionStyle Function(Map map, int depth) styleMap = _defaultMapStyle,
  CollectionStyle Function(List list, int depth) styleList = _defaultListStyle,
  ScalarStyle Function(String string, int depth) styleString =
      _defaultStringStyle,
}) {
  YamlNode wrap(Object? value, int depth) {
    if (value is YamlScalar) {
      wrapAsYamlNode(value); // assert valid scalar
      return value;
    } else if (value is YamlList) {
      for (final item in value.nodes) {
        wrapAsYamlNode(item); // assert valid scalar
      }
      return value;
    } else if (value is YamlMap) {
      /// Both [entry.key] and [entry.values] are guaranteed to be [YamlNode]s,
      /// so running this will just assert that they are valid scalars.
      for (final entry in value.nodes.entries) {
        wrapAsYamlNode(entry.key);
        wrapAsYamlNode(entry.value);
      }
      return value;
    } else if (value is Map) {
      return wrapAsYamlNode({
        for (final kv in value.entries)
          wrap(kv.key, depth + 1): wrap(kv.value, depth + 1),
      }, collectionStyle: styleMap(value, depth));
    } else if (value is List) {
      return wrapAsYamlNode({
        for (final v in value) wrap(v, depth + 1),
      }, collectionStyle: styleList(value, depth));
    } else if (value is String) {
      return wrapAsYamlNode(value, scalarStyle: styleString(value, depth));
    } else {
      return wrapAsYamlNode(value);
    }
  }

  return wrap(value, 0);
}

int _sizeOfScalar(dynamic value) => value == null ? 4 : '$value'.length;

CollectionStyle _defaultMapStyle(Map map, int depth) {
  if (map.values.any((value) => value is Map || value is List)) {
    return CollectionStyle.BLOCK;
  }
  final size = map.entries.fold<int>(
    0,
    (sum, entry) => sum + _sizeOfScalar(entry.key) + _sizeOfScalar(entry.value),
  );
  if (size < 80) {
    return CollectionStyle.FLOW;
  }
  return CollectionStyle.BLOCK;
}

CollectionStyle _defaultListStyle(List list, int depth) {
  if (list.any((value) => value is Map || value is List)) {
    return CollectionStyle.BLOCK;
  }
  final size = list.fold<int>(
    0,
    (sum, value) => sum + _sizeOfScalar(value),
  );
  if (size < 80) {
    return CollectionStyle.FLOW;
  }
  return CollectionStyle.BLOCK;
}

ScalarStyle _defaultStringStyle(String string, int depth) {
  if (string.contains('\n')) {
    return ScalarStyle.LITERAL;
  }
  if (string.length > 80) {
    return ScalarStyle.FOLDED;
  }
  if (!string.contains('\'')) {
    if (!string.contains('"')) {
      return ScalarStyle.PLAIN;
    }
    return ScalarStyle.SINGLE_QUOTED;
  }
  return ScalarStyle.DOUBLE_QUOTED;
}

https://pub.dev/documentation/yaml_edit/latest/yaml_edit/wrapAsYamlNode.html

Should this wrap recursively?

input (lists, strings, maps):

[{name: bla, packaging: dynamic, path: {path_type: absolute, uri: path/with spaces/bla.dll}, target: windows_x64}]

output:

- name: bla
  packaging: dynamic
  path:
    path_type: absolute
    uri: path/with spaces/bla.dll
  target: windows_x64

conversion

String _toYamlString(Object yamlEncoding) => (YamlEditor('')
      ..update(
          [],
          wrapAsYamlNode(
            yamlEncoding,
            collectionStyle: CollectionStyle.BLOCK,
            scalarStyle: ScalarStyle.DOUBLE_QUOTED,
          )))
    .toString();

Asked for quotes, but didn't get any.

The following results in an Unhandled Exception "Assertion failed: (package:yaml_edit) Modification did not result in expected result."

import 'dart:io';

import 'package:yaml_edit/yaml_edit.dart';

Future<void> main() async {
  YamlEditor yamlEditorFile =
      YamlEditor(File('test/gh_test.yml').readAsStringSync());

  try {
    // yamlEditorFile.insertIntoList(
    //     ['school'],
    //     3,
    //     {
    //       'student': {'first_name': 'Henry', 'last_name': 'Smith'}
    //     });

    yamlEditorFile.appendToList([
      'school'
    ], {
      'student': {'first_name': 'Henry', 'last_name': 'Smith'}
    });
  } on Exception catch (e) {
    print(e);
  }

  print(yamlEditorFile);
}

gh_test.yml is:

# comment
school:
  - student:
      first_name: Harry
      last_name: "Reynolds"
  - student:
      first_name: "Sally"
      last_name: Rheims
  - student:
      first_name: "George"
      last_name: "Silver"
teachers:
  - english:
      name: "Johnson"
  - science:
      name: "Smith"

The insertIntoList call results in the same if the index is the next one (i.e., 3 - commented code in example above).

Expected behavior in all cases is that it inserts it correctly in the school list after student George Silver.

Instead the result in both examples is that the inserted list item (Henry Smith) is inserted incorrectly as the first item of the next list (i.e., teachers) as shown by the "Modification did not result in expected result" message.":

> teachers:
>   - student:
>       first_name: Henry
>       last_name: Smith
>   - english:
>       name: "Johnson"
>   - science:
>       name: "Smith"

the full error message:

Unhandled exception:
Assertion failed: (package:yaml_edit) Modification did not result in expected result.

# YAML before edit:
> # comment
> school:
>   - student:
>       first_name: Harry
>       last_name: "Reynolds"
>   - student:
>       first_name: "Sally"
>       last_name: Rheims
>   - student:
>       first_name: "George"
>       last_name: "Silver"
> teachers:
>   - english:
>       name: "Johnson"
>   - science:
>       name: "Smith"

# YAML after edit:
> # comment
> school:
>   - student:

>       first_name: Harry
>       last_name: "Reynolds"
>   - student:
>       first_name: "Sally"
>       last_name: Rheims
>   - student:
>       first_name: "George"
>       last_name: "Silver"
> teachers:
>   - student:
>       first_name: Henry
>       last_name: Smith
>   - english:
>       name: "Johnson"
>   - science:
>       name: "Smith"

Please file an issue at:
https://github.com/google/dart-neats/issues/new?labels=pkg%3Ayaml_edit%2C+pending-triage&template=yaml_edit.md

#0      YamlEditor._performEdit
#1      YamlEditor.insertIntoList
#2      YamlEditor.appendToList
#3      main

#4      _delayEntrypointInvocation.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:297:19)
#5      _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:192:12)

Exited (255)

So it appears it can't detect the end of the list. The example yaml is correctly validated. If I insert a non-list in between the two lists in the example yaml file, for example the boolean "public: false", I get "Mapping Values are not allowed here" as it attempts to insert it under the boolean yaml:

Here's that error message:

Error on line 13, column 12: Mapping values are not allowed here. Did you miss a colon earlier?
   ╷
13 │   - student:
   │            ^
   ╵
# comment
school:
  - student:
      first_name: Harry
      last_name: "Reynolds"
  - student:
      first_name: "Sally"
      last_name: Rheims
  - student:
      first_name: "George"
      last_name: "Silver"
public: false
  - student:
      first_name: Henry
      last_name: Smith
teachers:
  - english:
      name: "Johnson"
  - science:
      name: "Smith"
Exited

I'd love an API (replaceMapEntry?) to replace an entire key/value pair:

final yamlEditor = YamlEditor('''
analyzer:
  foo: false
''');
  yamlEditor.replaceMapEntry(['analyzer', 'foo'], {'bar': true});
  print(yamlEditor);

/*
analyzer:
  bar: true
*/

The current methods for doing this don't work well for us:

• add/update bar, remove foo: results in conflicting SourceEdit offsets.
• remove foo, add/update bar: results in a flow-style map: analyzer: {foo: false}.

I'd be happy to contribute this API!

When updating a string value with forward slashes, the resulting string escapes the forward slashes unnecessarily:

final doc = YamlEditor('exampleKey: \${file(../../bar.yml)}');

doc.update(['exampleKey'], '\${file(../../foo.yml)}');

print(doc);
// exampleKey: ${file(..\/..\/bar.yml)}

My current workaround is to modify the resulting string:

doc.toString().replaceAll('\\/', '/')

It would be nice to customize that behaviour.

iam working on CLI features that see the content of the assets directory and add pathes to pubspec.yaml based on that it works with update if there is already a list in pubspec assets

    final doc = YamlEditor(pubspecContent);
    doc.update(['flutter','assets'], assets);

BUT if there is no assets key n the pubspec under flutter

flutter:
  uses-material-design: true

it throws exception

i think this is the expected behavior to throw when updating a null but how could i set value to a key that does not exist+