Ts-node-dev: File changes detected in the build folder, not the source folder

[simoami]

Hello,
Running the following command:

ts-node-dev --respawn --transpileOnly --project tsconfig.server.json ./server/index.ts",

compiles files to the build folder and runs the server successfully. However, file changes are not detected in the source tree. If on the other hand I change a file in the build folder, changes are detected.

Using ts-node version 8.6.2, typescript version 3.7.5, Node v10.17.0, Yarn v1.19.1

Sample output:

yarn dev
yarn run v1.19.1
$ ts-node-dev --respawn --debug --transpileOnly --project tsconfig.server.json ./server/index.ts
Using ts-node version 8.6.2, typescript version 3.7.5
[DEBUG] 00:34:58 Starting child process -r /var/folders/7c/lb9fsb0n1z9gdzfcdv07sp4h0000gn/T/ts-node-dev-hook-626995443417242.js /projects/test-service/node_modules/ts-node-dev/lib/wrap.js ./server/index.ts
[DEBUG] 00:34:58 /projects/test-service/server/index.ts compiled in 128 ms
[DEBUG] 00:34:58 /projects/test-service/build/plugins/tenant.js compiled in 25 ms
[DEBUG] 00:34:58 /projects/test-service/build/services/OrganizationService.js compiled in 24 ms
[DEBUG] 00:34:58 /projects/test-service/build/models/Organization.js compiled in 23 ms
[DEBUG] 00:34:58 /projects/test-service/build/models/BaseModel.js compiled in 39 ms
[DEBUG] 00:34:59 /projects/test-service/build/models/EnhancedQueryBuilder.js compiled in 22 ms
[DEBUG] 00:34:59 /projects/test-service/build/services/PersistentService.js compiled in 45 ms
[DEBUG] 00:34:59 /projects/test-service/build/lib/errors/index.js compiled in 20 ms
[DEBUG] 00:34:59 /projects/test-service/build/lib/errors/errors.js compiled in 45 ms
[DEBUG] 00:34:59 /projects/test-service/build/plugins/access-token.js compiled in 15 ms
[DEBUG] 00:34:59 /projects/test-service/build/lib/auth.js compiled in 30 ms
...
Server listening on 5000...

And here is the output when detecting a change in the output folder build/ which it shouldn't be watching:

[INFO] 00:53:42 Restarting: /projects/test-service/build/lib/database.js has been modified
[DEBUG] 00:53:42 /projects/test-service/build/lib/database.js compiled in 18 ms
[DEBUG] 00:53:42 Removing all watchers from files

tsconfig.json:

{
  "compileOnSave": false,
  "compilerOptions": {
    "jsx": "preserve",
    "allowJs": true,
    "alwaysStrict": true,
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "removeComments": false,
    "preserveConstEnums": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "sourceMap": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "baseUrl": "./",
    "rootDir": "./server",
    "paths": {
      "@models/*": [
        "server/models/*"
      ],
      "@controllers/*": [
        "server/controllers/*"
      ],
      "@services/*": [
        "server/services/*"
      ],
      "@lib/*": [
        "server/lib/*"
      ],
      "@plugins/*": [
        "server/plugins/*"
      ]
    },
    "experimentalDecorators": true,
    "typeRoots": [
      "./node_modules/@types",
      "server/types"
    ],
    "lib": ["es2018"],
    "target": "es2018"
  },
  "exclude": [
    "build",
    "node_modules"
  ]
}

tsconfig.server.json:

{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "module": "commonjs",
    "outDir": "build/"
  },
  "include": [
    "server/**/*.ts"
  ],
  "exclude": [
    "server/**/*.test.ts"
  ]
}

[lkiii]

I am experiencing the same behaviour. My ts files are located at src folder and my built files are stored at dist folder. Strange thing is that if I am editing ts files in src folder that ts-node-dev detects changes, but if the file is located src/***/*.ts then it is not detected, then only the dist folder changes are being detected. What could be a source of this issue?

@whitecolor maybe you have any ideas?

EDIT: I think I have found the cause of the problem. I was using module-alias/register and this was interfering with ts-node-dev

@simoami is there something similar used in your project?

[mielp]

Just so you know, a workaround is to make sure module-alias/register is never loaded when running in the ts-node-dev context. Luckily, it's a simple check against an environment variable:

if (!process.env.TS_NODE_DEV) {
  require('module-alias/register'); // for path resolution
}