Fails with cannot find module 'anltr4/index' with antlr4 4.9

[dmaffitt]

All is well with antlr4 4.8.0 but updating to 4.9 causes the following. I'm brand new in the javascript world so not very effective in debugging this. It seems there was an issue like this in 2018 https://github.com/mcchatman8009/antlr4-tool/issues/14. The only change I made was bumping antlr4 from 4.8 to 4.9.

yarn run v1.19.2 $ antlr4-tool --output-dir src/parser --language typescript grammar/DE6Parser.g4 grammar/DE6Lexer.g4 grammar/TagPath.g4 Compiling grammar/DE6Parser.g4, grammar/DE6Lexer.g4, grammar/TagPath.g4... internal/modules/cjs/loader.js:883 throw err; ^

Error: Cannot find module 'antlr4/index' Require stack:

• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/parser-util.js
• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/antlr-compiler.js
• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/index.js
• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/compile.js
• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/cli.js
• /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/app.js at Function.Module._resolveFilename (internal/modules/cjs/loader.js:880:15) at Function.resolve (internal/modules/cjs/helpers.js:94:19) at vmRequire (/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/parser-util.js:24:32) at evalmachine.:3:14 at Script.runInContext (vm.js:142:18) at Object.runInContext (vm.js:293:6) at Object.readParser (/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/parser-util.js:28:8) at AntlrCompiler.compileTypeScript (/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/antlr-compiler.js:66:37) at /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/index.js:40:78 at /Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/index.js:17:23 { code: 'MODULE_NOT_FOUND', requireStack: [ '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/parser-util.js', '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/antlr-compiler.js', '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/antlr-core/index.js', '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/compile.js', '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/cli.js', '/Users/drm/projects/nrg/dicomeditjs/de6js/node_modules/antlr4-tool/dist/app.js' ] } error Command failed with exit code 1.