From the analyzer log, it seems there was an error.
[16:39:23] [Analyzer] [Info] ==> {"jsonrpc":"2.0","method":"textDocument/didClose","params":{"textDocument":{"uri":"file:///D%3A/dev/clones/dart-sdk/sdk/pkg/analysis_server/test/src/services/correction/fix/merge_combinators_test.dart"}},"clientRequestTime":1741808363525}
[16:39:24] [Analyzer] [Info] <== Content-Length: 70464
Content-Type: application/vscode-jsonrpc; charset=utf-8
[16:39:24] [Analyzer] [Info] <== {"jsonrpc":"2.0","method":"textDocument/publishDiagnostics","params":{"diagnostics":[{"code":"extends_non_class","codeDescription":{"href":"https://dart.dev/diagnostics/extends_non_class"},"message":"Classes can only extend other classes.\nTry specifying a different superclass, or removing the extends clause.","range":{"end":{"character":69,"line":510},"start":{"character":44,"line":510}},"severity":1,"source":"dart"},{"code":"undefined_getter","codeDescription":{"href":"https://dart.dev/diagnostics/undefined_getter"},"message":"The getter 'MERGE_COMBINATORS_HIDE_HIDE' isn't defined for the type 'DartFixKind'.\nTry importing the library that defines 'MERGE_COMBINATORS_HIDE_HIDE', correcting the name to the name of an existing getter, or defining a getter or field named 'MERGE_COMBINATORS_HIDE_HIDE'.","range":{"end":{"character":61,"line":28},"start":{"character":34,"line":28}},"severity":1,"source":"dart"},{"code":"undefined_method","codeDescription":{"href":"https://dart.dev/diagnostics/undefined_method"},"message":"The method 'resolveTestCode' isn't defined for the type 'MergeHideUsingHideTest'.\nTry correcting the name to the name of an existing method, or defining a method named 'resolveTestCode'.","range":{"end":{"character":25,"line":31},"start":{"character":10,"line":31}},"severity":1,"source":"dart"},{"code":"undefined_method","codeDescription":{"href":"https://dart.dev/diagnostics/undefined_method"},"message":"The method 'assertHasFix' isn't defined for the type 'MergeHideUsingHideTest'.\nTry correcting the name to the name of an existing method, or defining a method named 'assertHasFix'.","range":{"end":{"character":22,"line":34},"start":{"character":10,"line":34}},"severity":1,"source":"dart"},{"code":"undefined_method","codeDescription":{"href":"https://dart.dev/diagnostics/undefined_method"},"message":"The method 'createAnalysisOptionsFile' isn't defined for the type 'MergeHideUsingHideTest'.\nTry correcting the name to the name of an existing metho…
[16:39:24] [Analyzer] [Info] <== Content-Length: 214
Content-Type: application/vscode-jsonrpc; charset=utf-8
{"jsonrpc":"2.0","method":"dart/textDocument/publishClosingLabels","params":{"labels":[],"uri":"file:///D:/dev/clones/dart-sdk/sdk/pkg/analysis_server/test/src/services/correction/fix/merge_combinators_test.dart"}}Content-Length: 23909
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{"jsonrpc":"2.0","method":"dart/textDocument/publishOutline","params":{"outline":{"children":[{"codeRange":{"end":{"character":1,"line":20},"start":{"character":0,"line":13}},"element":{"kind":"FUNCTION","name":"main","parameters":"()","range":{"end":{"character":9,"line":13},"start":{"character":5,"line":13}},"returnType":"void"},"range":{"end":{"character":1,"line":20},"start":{"character":0,"line":13}}},{"children":[{"codeRange":{"end":{"character":62,"line":25},"start":{"character":2,"line":25}},"element":{"kind":"GETTER","name":"errorCode","range":{"end":{"character":25,"line":25},"start":{"character":16,"line":25}},"returnType":"ErrorCode"},"range":{"end":{"character":62,"line":25},"start":{"character":2,"line":24}}},{"codeRange":{"end":{"character":62,"line":28},"start":{"character":2,"line":28}},"element":{"kind":"GETTER","name":"kind","range":{"end":{"character":18,"line":28},"start":{"character":14,"line":28}},"returnType":"FixKind"},"range":{"end":{"character":62,"line":28},"start":{"character":2,"line":27}}},{"codeRange":{"end":{"character":3,"line":37},"start":{"character":2,"line":30}},"element":{"kind":"METHOD","name":"test_export_hide_hide","parameters":"()","range":{"end":{"character":36,"line":30},"start":{"character":15,"line":30}},"returnType":"Future<void>"},"range":{"end":{"character":3,"line":37},"start":{"character":2,"line":30}}},{"codeRange":{"end":{"character":3,"line":47},"start":{"character":2,"line":39}},"element":{"kind":"METHOD","name":"test_export_hide_hide_lint","parameters":"()","range":{"end":{"character":41,"line":39},"start":{"character":15,"line":39}},"re…
[16:39:27] [General] [Error] Unexpected token '/', "/*error: e"... is not valid JSON
SyntaxError: Unexpected token '/', "/*error: e"... is not valid JSON
at JSON.parse (<anonymous>)
at PackageConfigJsonPackageMap.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13921:28)
at new PackageConfigJsonPackageMap (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13914:14)
at Function.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13826:24)
at Function.loadForProject (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13816:20)
at c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:28591:76
[16:39:27] [General] [Error] Unexpected token '/', "/*error: e"... is not valid JSON
SyntaxError: Unexpected token '/', "/*error: e"... is not valid JSON
at JSON.parse (<anonymous>)
at PackageConfigJsonPackageMap.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13921:28)
at new PackageConfigJsonPackageMap (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13914:14)
at Function.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13826:24)
at Function.loadForProject (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13816:20)
at c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:28591:76
[16:39:27] [General] [Error] Unexpected token '/', "/*error: e"... is not valid JSON
SyntaxError: Unexpected token '/', "/*error: e"... is not valid JSON
at JSON.parse (<anonymous>)
at PackageConfigJsonPackageMap.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13921:28)
at new PackageConfigJsonPackageMap (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13914:14)
at Function.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13826:24)
at Function.loadForProject (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13816:20)
at c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:28591:76
[16:39:27] [General] [Error] Unexpected token '/', "/*error: e"... is not valid JSON
SyntaxError: Unexpected token '/', "/*error: e"... is not valid JSON
at JSON.parse (<anonymous>)
at PackageConfigJsonPackageMap.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13921:28)
at new PackageConfigJsonPackageMap (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13914:14)
at Function.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13826:24)
at Function.loadForProject (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13816:20)
at c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:28591:76
[16:39:27] [General] [Error] Unexpected token '/', "/*error: e"... is not valid JSON
SyntaxError: Unexpected token '/', "/*error: e"... is not valid JSON
at JSON.parse (<anonymous>)
at PackageConfigJsonPackageMap.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13921:28)
at new PackageConfigJsonPackageMap (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13914:14)
at Function.load (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13826:24)
at Function.loadForProject (c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:13816:20)
at c:\Users\felip_0vh5fa6\.vscode\extensions\dart-code.dart-code-3.107.20250311\out\dist\extension.js:28591:76
[16:39:30] [Analyzer] [Info] <== Content-Length: 212
Content-Type: application/vscode-jsonrpc; charset=utf-8
[16:39:30] [Analyzer] [Info] <== {"jsonrpc":"2.0","method":"textDocument/publishDiagnostics","params":{"diagnostics":[],"uri":"file:///D:/dev/clones/dart-sdk/sdk/pkg/analysis_server/test/src/services/correction/fix/merge_combinators_test.dart"}}
[16:39:38] [Analyzer] [Info] <== Content-Length: 93