Default formatting changed in v4

With v4, after formatting JS file, trailing commas are added, and parentheses are added around single arguments.

When I downgrade to v3.20 and reformat, the commas and parentheses are removed.

Additional information

VS Code Version: 1.43.2

Prettier Extension Version: 4.*

OS and version: Mac 10.15.4

Prettier Log Output

["INFO" - 12:50:38 AM] Formatting /Users/me/gh/guide-api/src/resolvers/User.js
["INFO" - 12:50:38 AM] Using ignore file (if present) at /Users/me/gh/guide-api/.prettierignore
["INFO" - 12:50:38 AM] Using bundled version of prettier.
["INFO" - 12:50:38 AM] File Info:
{
  "ignored": false,
  "inferredParser": "babel"
}
["INFO" - 12:50:38 AM] Detected local configuration (i.e. .prettierrc or .editorconfig), VS Code configuration will not be used
["INFO" - 12:50:38 AM] Prettier Options:
{
  "filepath": "/Users/me/gh/guide-api/src/resolvers/User.js",
  "parser": "babel",
  "singleQuote": true,
  "semi": false
}
["INFO" - 12:50:38 AM] Formatting completed in 30.940685ms.

This bug also experienced by @sbreakey

[lorensr]

Ah, thanks!

For others: I had to add these lines to my project’s .prettierrc:

trailingComma: none
arrowParens: avoid

Note that a local config file overrides config in VS Code settings.

[ntotten]

This is the expected behavior in the new version of Prettier.

See announcement blog post for changes: https://prettier.io/blog/2020/03/21/2.0.0.html

See VS Code extension docs for how configuration works: https://github.com/prettier/prettier-vscode#configuration