process.on('SIGTERM') event handlers are not executed in main process

[nathanielks]

Describe the bug Any signal event handlers (SIGINT, SIGTERM) registered in the main process file (background.js) are not executed when canceling the webpack dev server.

To Reproduce

• Download reproduction project: process-bug.zip
• unzip and cd into directory
• npm install
• npm run electron:serve
• Ctrl-C

The console should print main: SIGINT, but it won't. This tells me the event handlers are not executing.

Expected behavior When hitting ctrl-c, process signal event handlers in the main electron process should execute.

Environment (please complete the following information):

• (if possible) link to your repo: process-bug.zip
• terminal output from running vue info:

Environment Info:

 System:
   OS: macOS 11.3.1
   CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
 Binaries:
   Node: 14.16.0 - /usr/local/n/bin/node
   Yarn: 1.22.10 - /usr/local/bin/yarn
   npm: 7.7.4 - /usr/local/n/bin/npm
 Browsers:
   Chrome: Not Found
   Edge: Not Found
   Firefox: 88.0.1
   Safari: 14.1
 npmPackages:
   @vue/babel-helper-vue-jsx-merge-props:  1.2.1
   @vue/babel-helper-vue-transform-on:  1.0.2
   @vue/babel-plugin-jsx:  1.0.6
   @vue/babel-plugin-transform-vue-jsx:  1.2.1
   @vue/babel-preset-app:  4.5.13
   @vue/babel-preset-jsx:  1.2.4
   @vue/babel-sugar-composition-api-inject-h:  1.2.1
   @vue/babel-sugar-composition-api-render-instance:  1.2.4
   @vue/babel-sugar-functional-vue:  1.2.2
   @vue/babel-sugar-inject-h:  1.2.2
   @vue/babel-sugar-v-model:  1.2.3
   @vue/babel-sugar-v-on:  1.2.3
   @vue/cli-overlay:  4.5.13
   @vue/cli-plugin-babel: ~4.5.0 => 4.5.13
   @vue/cli-plugin-eslint: ~4.5.0 => 4.5.13
   @vue/cli-plugin-router:  4.5.13
   @vue/cli-plugin-vuex:  4.5.13
   @vue/cli-service: ~4.5.0 => 4.5.13
   @vue/cli-shared-utils:  4.5.13
   @vue/component-compiler-utils:  3.2.0
   @vue/preload-webpack-plugin:  1.1.2
   @vue/web-component-wrapper:  1.3.0
   eslint-plugin-vue: ^6.2.2 => 6.2.2
   vue: ^2.6.11 => 2.6.12
   vue-cli-plugin-electron-builder: ~2.0.0 => 2.0.0
   vue-eslint-parser:  7.6.0
   vue-hot-reload-api:  2.3.4
   vue-loader:  15.9.7 (16.2.0)
   vue-style-loader:  4.1.3
   vue-template-compiler: ^2.6.11 => 2.6.12
   vue-template-es2015-compiler:  1.9.1
 npmGlobalPackages:
   @vue/cli: 4.5.12

[nathanielks]

For further example, I've put together another way to demonstrate how it should be behaving: process-test.zip

• Download, unzip, cd into the directory
• npm install
• node .
• ctrl-c

You should see logs like this:

pid: 49895
creating server process
[parent][stdout] tick
^Cindex: sigint
parent: received SIGINT
[parent][stdout] child: received SIGINT
[parent][stdout] child exit
[parent][event] disconnect,[]
[parent][event] exit,[1,null]
[parent][event] close,[1,null]

This demonstrates that each sub process was able to register an event handler for SIGINT. The electron main process, however, does not demonstrate this behavior for a reason I have not yet been able to ascertain.