Revert "Revert "Fix syntax and semantic error detection in yaml_edit. (#2284)""

[jonasfj]

Reverts #2295 which reverted #2284

Before we can land this we need to fix/disable/skip the test in analysis_server that this caused when rolling into Dart SDK, see #2289

test logs

/=================================================================================================================================================================\
| analyzer-unittest-asserts-release-linux:pkg/analysis_server/test/src/services/correction/fix/ignore_diagnostic_test broke (Pass -> RuntimeError, expected Pass) |
\=================================================================================================================================================================/

--- Command "vm" (took 28.000868s):
DART_CONFIGURATION=ReleaseX64 out/ReleaseX64/dart-sdk/bin/dart --enable_asserts -Dtest_runner.configuration=analyzer-unittest-asserts-release-linux --ignore-unrecognized-flags --packages=/b/s/w/ir/.dart_tool/package_config.json /b/s/w/ir/pkg/analysis_server/test/src/services/correction/fix/ignore_diagnostic_test.dart

exit code:
255

stdout:
00:00 �[32m+0�[0m: IgnoreDiagnosticAnalysisOptionFileTest | test_addFixToExistingErrorMap�[0m

00:01 �[32m+1�[0m: IgnoreDiagnosticAnalysisOptionFileTest | test_emptyAnalysisOptionsFile�[0m

00:01 �[32m+2�[0m: IgnoreDiagnosticAnalysisOptionFileTest | test_invalidAnalysisOptionsFormat�[0m

00:02 �[32m+2�[0m�[31m -1�[0m: IgnoreDiagnosticAnalysisOptionFileTest | test_invalidAnalysisOptionsFormat �[1m�[31m[E]�[0m�[0m

  Assertion failed: (package:yaml_edit) Failed to produce valid YAML after modification.
  
  # YAML before edit:
  > analyzer:
  >   linter:
  > 
  
  # YAML after edit:
  > analyzer:
  >   errors:
  >     unused_local_variable: ignore:
  > 
  
  Please file an issue at:
  https://github.com/dart-lang/yaml_edit/issues/new?labels=bug
  

  package:yaml_edit/src/editor.dart 576:7                                                YamlEditor._performEdit
  package:yaml_edit/src/editor.dart 272:14                                               YamlEditor.update
  package:analysis_server_plugin/src/correction/ignore_diagnostic.dart 98:16             IgnoreDiagnosticInAnalysisOptionsFile.compute.<fn>
  package:analyzer_plugin/src/utilities/change_builder/change_builder_core.dart 264:18   ChangeBuilderImpl.addYamlFileEdit
  package:analysis_server_plugin/src/correction/ignore_diagnostic.dart 72:19             IgnoreDiagnosticInAnalysisOptionsFile.compute
  package:analysis_server_plugin/src/correction/fix_processor.dart 93:24                 FixProcessor._addFromProducer
  package:analysis_server_plugin/src/correction/fix_processor.dart 171:15                FixProcessor._addFromProducers
  ===== asynchronous gap ===========================
  package:analysis_server_plugin/src/correction/fix_processor.dart 65:5                  FixProcessor.compute
  ===== asynchronous gap ===========================
  package:analysis_server_plugin/src/correction/fix_processor.dart 23:8                  computeFixes
  ===== asynchronous gap ===========================
  pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart 656:12         FixProcessorTest._computeFixes
  ===== asynchronous gap ===========================
  pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart 604:17         FixProcessorTest._assertNoFix
  ===== asynchronous gap ===========================
  pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart 482:5          FixProcessorTest.assertNoFix
  ===== asynchronous gap ===========================
  pkg/analysis_server/test/src/services/correction/fix/ignore_diagnostic_test.dart 73:5  IgnoreDiagnosticAnalysisOptionFileTest.test_invalidAnalysisOptionsFormat
  ===== asynchronous gap ===========================
  package:test_reflective_loader/test_reflective_loader.dart 281:5                       _runTest
  ===== asynchronous gap ===========================
  package:test_reflective_loader/test_reflective_loader.dart 164:19                      _addTestsIfTopLevelSuite.runTests.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/declarer.dart 253:15                                      Declarer.test.<fn>.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/declarer.dart 250:11                                      Declarer.test.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/invoker.dart 318:9                                        Invoker._waitForOutstandingCallbacks.<fn>
  

00:02 �[32m+2�[0m�[31m -1�[0m: IgnoreDiagnosticAnalysisOptionFileTest | test_noAnalysisOptionsFile�[0m

[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:bazel_worker	1.1.5	already published at pub.dev
package:benchmark_harness	2.4.0	already published at pub.dev
package:boolean_selector	2.1.2	already published at pub.dev
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package:stack_trace	1.12.2-wip	(error) pubspec version (1.12.2-wip) and changelog (1.12.2-dev) don't agree
package:stream_channel	2.1.4	already published at pub.dev
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[gemini-code-assist]

Code Review

This pull request reverts a previous revert, re-introducing a fix for syntax and semantic error detection in yaml_edit. The changes in _performEdit are a significant improvement. The previous implementation had several issues: it mutated the editor's state before validation, didn't correctly handle parsing errors for invalid YAML modifications, and failed to update alias tracking information after a change. The new implementation fixes all these issues by using a temporary variable for the updated YAML, validating both syntax and semantic correctness within try-catch blocks, and only updating the internal state after all checks have passed. This makes the editing process much more robust and reliable. The code is clean, well-commented, and follows Dart best practices. The change looks great.

[github-actions]

PR Health

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pkgs/bazel_worker/benchmark/benchmark.dart
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pkgs/pubspec_parse/test/git_uri_test.dart
pkgs/stack_trace/example/example.dart
pkgs/watcher/test/custom_watcher_factory_test.dart
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yaml_edit	None	2.2.3	2.2.3	2.2.3	✔️

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