Bug - Problem when using typescript ESNext + babel and nullish coalescing operator when assigning a property from this with a default value

[fdeslandes-wk]

Issue description or question

When using typescript configured with ESNext and babel as a preprocessor, the nullish coalescing operator causes problems when used to assign a value from the current object to an object property.

ex:
const obj = { a: 'test', get b() { return { val: this.a ?? 'other', } } };

This was working with the previous Wallaby version.

You can test with the following minimal-ish example from a previous bug report, which I extended with the new case:
wallaby-typescript-babel.zip

You will get this error:
[Error] Postprocessor run failure: Failed to run preprocessors on src/file.js, SyntaxError: unknown: Unexpected keyword 'this' (12:60) 
[Error]  
[Error] 10 | get b() { 
[Error] 11 | var $$c = $$wf(1); 
[Error] > 12 | return $$w(1, 13, $$c), { val: $$w(1, 14, $$c), this.a ?? $$w(1, 15, $$c), 'test' }; 
[Error] | ^ 
[Error] 13 | } 
[Error] 14 | }); 
[Error] 15 | $_$wpe(1); 
[Error] at Parser.raise (.\node_modules@babel\parser\lib\index.js:7012:17) 
[Error] at Parser.checkReservedWord (.\node_modules@babel\parser\lib\index.js:10397:12) 
[Error] at Parser.parseObjectProperty (.\node_modules@babel\parser\lib\index.js:10118:12) 
[Error] at Parser.parseObjPropValue (.\node_modules@babel\parser\lib\index.js:10138:101) 
[Error] at Parser.parseObjectMember (.\node_modules@babel\parser\lib\index.js:10062:10) 
[Error] at Parser.parseObj (.\node_modules@babel\parser\lib\index.js:9982:25) 
[Error] at Parser.parseExprAtom (.\node_modules@babel\parser\lib\index.js:9604:28) 
[Error] at Parser.parseExprSubscripts (.\node_modules@babel\parser\lib\index.js:9237:23) 
[Error] at Parser.parseMaybeUnary (.\node_modules@babel\parser\lib\index.js:9217:21) 
[Error] at Parser.parseExprOps (.\node_modules@babel\parser\lib\index.js:9083:23) 
[Error] at Parser.parseMaybeConditional (.\node_modules@babel\parser\lib\index.js:9056:23) 
[Error] at Parser.parseMaybeAssign (.\node_modules@babel\parser\lib\index.js:9015:21) 
[Error] at Parser.parseExpression (.\node_modules@babel\parser\lib\index.js:8972:36) 
[Error] at Parser.parseReturnStatement (.\node_modules@babel\parser\lib\index.js:11059:28) 
[Error] at Parser.parseStatementContent (.\node_modules@babel\parser\lib\index.js:10738:21) 
[Error] at Parser.parseStatement (.\node_modules@babel\parser\lib\index.js:10690:17) 
[Error] at Parser.parseBlockOrModuleBlockBody (.\node_modules@babel\parser\lib\index.js:11266:25) 
[Error] at Parser.parseBlockBody (.\node_modules@babel\parser\lib\index.js:11253:10) 
[Error] at Parser.parseBlock (.\node_modules@babel\parser\lib\index.js:11237:10) 
[Error] at Parser.parseFunctionBody (.\node_modules@babel\parser\lib\index.js:10256:24) 
[Error] at Parser.parseFunctionBodyAndFinish (.\node_modules@babel\parser\lib\index.js:10226:10) 
[Error] at Parser.parseMethod (.\node_modules@babel\parser\lib\index.js:10180:10) 
[Error] at Parser.parseObjectMethod (.\node_modules@babel\parser\lib\index.js:10103:12) 
[Error] at Parser.parseObjPropValue (.\node_modules@babel\parser\lib\index.js:10138:23) 
[Error] at Parser.parseObjectMember (.\node_modules@babel\parser\lib\index.js:10062:10) 
[Error] at Parser.parseObj (.\node_modules@babel\parser\lib\index.js:9982:25) 
[Error] at Parser.parseExprAtom (.\node_modules@babel\parser\lib\index.js:9604:28) 
[Error] at Parser.parseExprSubscripts (.\node_modules@babel\parser\lib\index.js:9237:23) 
[Error] at Parser.parseMaybeUnary (.\node_modules@babel\parser\lib\index.js:9217:21) 
[Error] at Parser.parseExprOps (.\node_modules@babel\parser\lib\index.js:9083:23) 
[Error] at Parser.parseMaybeConditional (.\node_modules@babel\parser\lib\index.js:9056:23) 
[Error] at Parser.parseMaybeAssign (.\node_modules@babel\parser\lib\index.js:9015:21) 
[Error] at Parser.parseParenAndDistinguishExpression (.\node_modules@babel\parser\lib\index.js:9799:28) 
[Error] at Parser.parseExprAtom (.\node_modules@babel\parser\lib\index.js:9582:21) 
[Error] at Parser.parseExprSubscripts (.\node_modules@babel\parser\lib\index.js:9237:23) 
[Error] at Parser.parseMaybeUnary (.\node_modules@babel\parser\lib\index.js:9217:21) 
[Error] at Parser.parseExprOps (.\node_modules@babel\parser\lib\index.js:9083:23) 
[Error] at Parser.parseMaybeConditional (.\node_modules@babel\parser\lib\index.js:9056:23) 
[Error] at Parser.parseMaybeAssign (.\node_modules@babel\parser\lib\index.js:9015:21) 
[Error] at Parser.parseVar (.\node_modules@babel\parser\lib\index.js:11341:26) 
[Error] at Parser.parseVarStatement (.\node_modules@babel\parser\lib\index.js:11160:10) 
[Error] at Parser.parseStatementContent (.\node_modules@babel\parser\lib\index.js:10757:21) 
[Error] at Parser.parseStatement (.\node_modules@babel\parser\lib\index.js:10690:17) 
[Error] at Parser.parseBlockOrModuleBlockBody (.\node_modules@babel\parser\lib\index.js:11266:25) 
[Error] at Parser.parseBlockBody (.\node_modules@babel\parser\lib\index.js:11253:10) 
[Error] at Parser.parseTopLevel (.\node_modules@babel\parser\lib\index.js:10621:10) 
[Error] at Parser.parse (.\node_modules@babel\parser\lib\index.js:12131:10) 
[Error] at parse (.\node_modules@babel\parser\lib\index.js:12182:38) 
[Error] at parser (.\node_modules@babel\core\lib\transformation\normalize-file.js:187:34) 
[Error] at normalizeFile (.\node_modules@babel\core\lib\transformation\normalize-file.js:113:11) 
[Error] at runSync (.\node_modules@babel\core\lib\transformation\index.js:44:43) 
[Error] at transformSync (.\node_modules@babel\core\lib\transform.js:43:38) 
[Error] at Object.transform (.\node_modules@babel\core\lib\transform.js:22:38) 
[Error] at src/**/*.js (.\wallaby.js:45:36) 
[Error] at process._tickCallback (internal/process/next_tick.js:61:11) 

Wallaby diagnostics report

{ editorVersion: '1.46.1',
  pluginVersion: '1.0.215',
  editorType: 'VSCode',
  osVersion: 'win32 10.0.18363',
  nodeVersion: 'v10.19.0',
  coreVersion: '1.0.922',
  config:
   { files: [ { pattern: 'src/**/*.ts', ignore: false, trigger: true, load: true, instrument: true, order: 1 } ],
     filesWithNoCoverageCalculated: [ 'node_modules/**/*' ],
     tests: [ { pattern: 'src/**/*spec.ts', ignore: false, trigger: true, load: true, test: true, order: 2 } ],
     testFramework: { version: 'mocha@3.2.0', configurator: 'mocha@2.0.1', reporter: 'mocha@2.0.1', starter: 'mocha@2.0.1' },
     compilers: { '**/*.?(lit)coffee?(.md)': [Function] },
     preprocessors: { 'src/**/*.js': [Function: src/**/*.js] },
     debug: true,
     workers: { initial: 1, regular: 1, recycle: false },
     hints:
      { ignoreCoverage: '__REGEXP /ignore coverage/',
        ignoreCoverageForFile: '__REGEXP /ignore file coverage/',
        commentAutoLog: '?',
        testFileSelection: { include: '__REGEXP /file\\.only/', exclude: '__REGEXP /file\\.skip/' } },
     env: { kind: 'chrome', type: 'browser', params: {}, viewportSize: { width: 800, height: 600 }, options: { width: 800, height: 600 }, bundle: true },
     diagnostics: {},
     runAllTestsInAffectedTestFile: false,
     updateNoMoreThanOneSnapshotPerTestFileRun: false,
     maxConsoleMessagesPerTest: 100,
     autoConsoleLog: true,
     delays: { run: 0, edit: 100, update: 0 },
     teardown: undefined,
     automaticTestFileSelection: true,
     runSelectedTestsOnly: false,
     extensions: {},
     reportUnhandledPromises: false,
     throwOnBeforeUnload: true,
     slowTestThreshold: 75,
     lowCoverageThreshold: 80,
     loose: undefined,
     configCode:
      'const babel = require(\'@babel/core\');\r\n\r\nmodule.exports = (w) => {\r\n  const babelCfg = {\r\n    sourceMap: true,\r\n    presets: [\r\n      [\'@babel/preset-env\', {\r\n        targets: {\r\n          browsers: [\'last 1 Chrome versions\'],\r\n        },\r\n        forceAllTransforms: true,\r\n        // Allow the use of native async await despite forceAllTransforms\r\n        exclude: [\'transform-regenerator\', \'transform-async-to-generator\'],\r\n      }],\r\n    ],\r\n    plugins: [\r\n      \'@babel/plugin-proposal-nullish-coalescing-operator\',\r\n      \'@babel/plugin-proposal-optional-chaining\',\r\n      \'@babel/plugin-proposal-object-rest-spread\',\r\n    ],\r\n  };\r\n\r\n\r\n  return {\r\n    files: [\r\n      \'src/**/*.ts\',\r\n    ],\r\n\r\n    filesWithNoCoverageCalculated: [\r\n      \'node_modules/**/*\',\r\n    ],\r\n\r\n    tests: [\r\n      \'src/**/*spec.ts\',\r\n    ],\r\n\r\n    testFramework: \'mocha\',\r\n\r\n    compilers: {\r\n      \'src/**/*.ts\': w.compilers.typeScript({ orderFilesByReferenceComments: true, noImplicitAny: false }),\r\n    },\r\n\r\n    preprocessors: {\r\n      /* Pre-processor is to late, since wallaby fails in instrumentalization phase*/\r\n      \'src/**/*.js\': file => babel.transform(file.content, babelCfg),\r\n    },\r\n    debug: true,\r\n    workers: {\r\n      initial: 1,\r\n      regular: 1,\r\n    },\r\n\r\n    hints: {\r\n      ignoreCoverage: /ignore coverage/,\r\n    },\r\n\r\n    env: {\r\n      kind: \'chrome\',\r\n    },\r\n  };\r\n};\r\n' },
  packageJSON:
   { dependencies:
      { '@babel/core': '^7.7.0',
        '@babel/plugin-proposal-nullish-coalescing-operator': '^7.7.0',
        '@babel/plugin-proposal-object-rest-spread': '^7.7.0',
        '@babel/plugin-proposal-optional-chaining': '^7.7.0',
        '@babel/polyfill': '^7.7.0',
        '@babel/preset-env': '^7.7.0',
        'babel-eslint': '~10.0.2',
        eslint: '~6.8.0',
        'eslint-config-airbnb-base': '~14.0.0',
        'eslint-plugin-import': '^2.14.0',
        tslint: '^5.18.0',
        'tslint-config-airbnb': '^5.11.1',
        typescript: '^3.7.4',
        typings: '^2.1.1' },
     devDependencies: undefined },
  fs: { numberOfFiles: 1 },
  debug:
   [ '2020-07-07T16:44:45.289Z project Wallaby Node version: v10.19.0\n',
     '2020-07-07T16:44:45.290Z project Wallaby config: F:\\fred\\Downloads\\wallaby-typescript-babel\\wallaby.js\n',
     '2020-07-07T16:44:45.922Z project File cache: C:\\Users\\frede\\.vscode\\extensions\\wallabyjs.wallaby-vscode-1.0.215\\projects\\bcd04bbc7f2799e5\n',
     '2020-07-07T16:44:45.967Z uiService Listening port 51236\n',
     '2020-07-07T16:44:45.984Z project package.json file change detected, invalidating local cache\n',
     '2020-07-07T16:44:46.020Z workers Parallelism for initial run: 1, for regular run: 1\n',
     '2020-07-07T16:44:46.020Z workers Starting run worker instance #0\n',
     '2020-07-07T16:44:46.022Z workers Web server is listening at 54911\n',
     '2020-07-07T16:44:46.035Z project File cache requires some updates, waiting required files from IDE\n',
     '2020-07-07T16:44:46.538Z workers Started run worker instance (immediate) #0\n',
     '2020-07-07T16:44:46.578Z project Stopping process pool\n',
     '2020-07-07T16:44:46.579Z project Running postprocessor\n',
     '2020-07-07T16:44:46.581Z postprocessor New TypeScript language service is required\n',
     '2020-07-07T16:44:47.287Z project Error: Failed to run preprocessors on src/file.js, SyntaxError: unknown: Unexpected keyword \'this\' (12:60)\n\n  10 |     get b() {\n  11 |         var $_$c = $_$wf(1);\n> 12 |         return $_$w(1, 13, $_$c), { val: $_$w(1, 14, $_$c), this.a ?? $_$w(1, 15, $_$c), \'test\' };\n     |                                                             ^\n  13 |     }\n  14 | });\n  15 | $_$wpe(1);\n    at Parser.raise (.\\node_modules\\@babel\\parser\\lib\\index.js:7012:17)\n    at Parser.checkReservedWord (.\\node_modules\\@babel\\parser\\lib\\index.js:10397:12)\n    at Parser.parseObjectProperty (.\\node_modules\\@babel\\parser\\lib\\index.js:10118:12)\n    at Parser.parseObjPropValue (.\\node_modules\\@babel\\parser\\lib\\index.js:10138:101)\n    at Parser.parseObjectMember (.\\node_modules\\@babel\\parser\\lib\\index.js:10062:10)\n    at Parser.parseObj (.\\node_modules\\@babel\\parser\\lib\\index.js:9982:25)\n    at Parser.parseExprAtom (.\\node_modules\\@babel\\parser\\lib\\index.js:9604:28)\n    at Parser.parseExprSubscripts (.\\node_modules\\@babel\\parser\\lib\\index.js:9237:23)\n    at Parser.parseMaybeUnary (.\\node_modules\\@babel\\parser\\lib\\index.js:9217:21)\n    at Parser.parseExprOps (.\\node_modules\\@babel\\parser\\lib\\index.js:9083:23)\n    at Parser.parseMaybeConditional (.\\node_modules\\@babel\\parser\\lib\\index.js:9056:23)\n    at Parser.parseMaybeAssign (.\\node_modules\\@babel\\parser\\lib\\index.js:9015:21)\n    at Parser.parseExpression (.\\node_modules\\@babel\\parser\\lib\\index.js:8972:36)\n    at Parser.parseReturnStatement (.\\node_modules\\@babel\\parser\\lib\\index.js:11059:28)\n    at Parser.parseStatementContent (.\\node_modules\\@babel\\parser\\lib\\index.js:10738:21)\n    at Parser.parseStatement (.\\node_modules\\@babel\\parser\\lib\\index.js:10690:17)\n    at Parser.parseBlockOrModuleBlockBody (.\\node_modules\\@babel\\parser\\lib\\index.js:11266:25)\n    at Parser.parseBlockBody (.\\node_modules\\@babel\\parser\\lib\\index.js:11253:10)\n    at Parser.parseBlock (.\\node_modules\\@babel\\parser\\lib\\index.js:11237:10)\n    at Parser.parseFunctionBody (.\\node_modules\\@babel\\parser\\lib\\index.js:10256:24)\n    at Parser.parseFunctionBodyAndFinish (.\\node_modules\\@babel\\parser\\lib\\index.js:10226:10)\n    at Parser.parseMethod (.\\node_modules\\@babel\\parser\\lib\\index.js:10180:10)\n    at Parser.parseObjectMethod (.\\node_modules\\@babel\\parser\\lib\\index.js:10103:12)\n    at Parser.parseObjPropValue (.\\node_modules\\@babel\\parser\\lib\\index.js:10138:23)\n    at Parser.parseObjectMember (.\\node_modules\\@babel\\parser\\lib\\index.js:10062:10)\n    at Parser.parseObj (.\\node_modules\\@babel\\parser\\lib\\index.js:9982:25)\n    at Parser.parseExprAtom (.\\node_modules\\@babel\\parser\\lib\\index.js:9604:28)\n    at Parser.parseExprSubscripts (.\\node_modules\\@babel\\parser\\lib\\index.js:9237:23)\n    at Parser.parseMaybeUnary (.\\node_modules\\@babel\\parser\\lib\\index.js:9217:21)\n    at Parser.parseExprOps (.\\node_modules\\@babel\\parser\\lib\\index.js:9083:23)\n    at Parser.parseMaybeConditional (.\\node_modules\\@babel\\parser\\lib\\index.js:9056:23)\n    at Parser.parseMaybeAssign (.\\node_modules\\@babel\\parser\\lib\\index.js:9015:21)\n    at Parser.parseParenAndDistinguishExpression (.\\node_modules\\@babel\\parser\\lib\\index.js:9799:28)\n    at Parser.parseExprAtom (.\\node_modules\\@babel\\parser\\lib\\index.js:9582:21)\n    at Parser.parseExprSubscripts (.\\node_modules\\@babel\\parser\\lib\\index.js:9237:23)\n    at Parser.parseMaybeUnary (.\\node_modules\\@babel\\parser\\lib\\index.js:9217:21)\n    at Parser.parseExprOps (.\\node_modules\\@babel\\parser\\lib\\index.js:9083:23)\n    at Parser.parseMaybeConditional (.\\node_modules\\@babel\\parser\\lib\\index.js:9056:23)\n    at Parser.parseMaybeAssign (.\\node_modules\\@babel\\parser\\lib\\index.js:9015:21)\n    at Parser.parseVar (.\\node_modules\\@babel\\parser\\lib\\index.js:11341:26)\n    at Parser.parseVarStatement (.\\node_modules\\@babel\\parser\\lib\\index.js:11160:10)\n    at Parser.parseStatementContent (.\\node_modules\\@babel\\parser\\lib\\index.js:10757:21)\n    at Parser.parseStatement (.\\node_modules\\@babel\\parser\\lib\\index.js:10690:17)\n    at Parser.parseBlockOrModuleBlockBody (.\\node_modules\\@babel\\parser\\lib\\index.js:11266:25)\n    at Parser.parseBlockBody (.\\node_modules\\@babel\\parser\\lib\\index.js:11253:10)\n    at Parser.parseTopLevel (.\\node_modules\\@babel\\parser\\lib\\index.js:10621:10)\n    at Parser.parse (.\\node_modules\\@babel\\parser\\lib\\index.js:12131:10)\n    at parse (.\\node_modules\\@babel\\parser\\lib\\index.js:12182:38)\n    at parser (.\\node_modules\\@babel\\core\\lib\\transformation\\normalize-file.js:187:34)\n    at normalizeFile (.\\node_modules\\@babel\\core\\lib\\transformation\\normalize-file.js:113:11)\n    at runSync (.\\node_modules\\@babel\\core\\lib\\transformation\\index.js:44:43)\n    at transformSync (.\\node_modules\\@babel\\core\\lib\\transform.js:43:38)\n    at Object.transform (.\\node_modules\\@babel\\core\\lib\\transform.js:22:38)\n    at src/**/*.js (.\\wallaby.js:45:36)\n    at process._tickCallback (internal/process/next_tick.js:61:11)\n    at c:\\Users\\frede\\.vscode\\extensions\\wallabyjs.wallaby-vscode-1.0.215\\wallaby\\server.js:24:5923\n    at process._tickCallback (internal/process/next_tick.js:68:7)\n',
     '2020-07-07T16:44:47.288Z project Test run finished\n',
     '2020-07-07T16:44:47.288Z project Test run data re-queued\n' ] }

[ArtemGovorov]

Thanks for submitting the bug report. The bug is fixed and the fix is published in the latest core v.1.0.923.