Doesn't work with global ESLint config
linter-eslint has a global option for falling back to ~/.eslintrc config if no configs are found locally.

Your README says prettier-atom looks up system tree for configs, but it doesn't seem to be working.
Here's my prettier-atom config:

Atom version: 1.19.7
prettier-atom version: 0.38.0
prettier version: 1.6.1
prettier-eslint version: 6.4.3
prettier-atom configuration: {
"formatOnSaveOptions": {
"enabled": true,
"showInStatusBar": true,
"respectEslintignore": true,
"javascriptScopes": [
"source.js",
"source.jsx",
"source.js.jsx",
"source.babel",
"source.js-semantic",
"text.html.basic",
"text.html.vue"
],
"typescriptScopes": [
"source.ts",
"source.tsx",
"source.ts.tsx"
],
"cssScopes": [
"source.css",
"source.less",
"source.css.less",
"source.scss",
"source.css.scss"
],
"jsonScopes": [
"source.json"
],
"graphQlScopes": [
"source.graphql"
],
"excludedGlobs": [],
"whitelistedGlobs": [],
"isDisabledIfNotInPackageJson": false
},
"prettierOptions": {
"singleQuote": true,
"bracketSpacing": true,
"semi": true,
"useTabs": false,
"jsxBracketSameLine": false,
"printWidth": 80,
"tabWidth": "auto",
"trailingComma": "none",
"parser": "babylon"
},
"useEslint": true,
"useEditorConfig": true,
"prettierEslintOptions": {
"prettierLast": false
}
}
It'd be nice if you could config to work with global .editorconfig as well.
ESLint config resolution is supposed to be handled by prettier-eslint.
I think it's possible ESLint is picking up a config while crawling in the directory tree.
Can you try to run eslint --print-config your-file.js and see what it gets?
It seems like it is getting the correct config.
I think I figured it out:

Warns to disable linter-eslint "Fix on Save", but if you disable that, then it doesn't work with prettier-eslint.
So you need to enable both linter-eslint and prettier-atom.
Perhaps this recommendation can be removed?
prettier-eslint should not depend on linter-eslint to make it work.
The initial problem remains unsolved here.
prettier-eslint has a logger that you can enable to see what's happening.
Open DevTools in Atom, and run in the console:
process.env.LOG_LEVEL='debug'
// or for more detailed traces
process.env.LOG_LEVEL='trace'
Then execute a format with ESLint integration enabled.
PS: I can't reproduce the issue. It can find my fallback config in my user dir.
prettier-eslint [DEBUG]: There was a problem finding the eslint module. Using prettier-eslint's version. Cannot find module 'eslint' Error: Cannot find module 'eslint'
I'm trying to use a global prettier-eslint. It seems like it's not detecting that, whereas linter-eslint does have options for global eslint configs. That would explain why enabling both "Fix on Save"s worked, but isn't ideal.
Good solution: be able to specify global prettier-eslint and global eslint config, e.g. linter-eslint's settings page.
Not sure if it'd be better to step up tree or just allow people to specify a global prettier-eslint install and/or eslint config. Seems like specifying would leave less room for bugs and might be why the linter-eslint team went that route.
The strange thing is that, it should be stepping up the tree as-is?
prettier-eslint completely relies on eslints CLIEngines getConfigForFile function to get the config based on the file being linted or fall back to defaults if the text being linted isn't from a file (new unsaved file).
If this helps at all, I'm having the same problem with prettier-eslint finding the file in the project path (one level higher than the package.json). Everything was has been working fine for months until I just noticed the change in formatting using ctrl+alt+f.
/Users/owner/.atom/packages/prettier-atom/node_modules/loglevel-colored-level-prefix/dist/index.js:54 prettier-eslint [DEBUG]: There was a problem finding the prettier module. Using prettier-eslint's version. Cannot find module 'prettier' Error: Cannot find module 'prettier'
at Module._resolveFilename (module.js:470:15)
at Module._resolveFilename (/Applications/Atom.app/Contents/Resources/electron.asar/common/reset-search-paths.js:35:12)
at Function.get_Module._resolveFilename (/Applications/Atom.app/Contents/Resources/app/src/module-cache.js:354:58)
at Function.requireRelative.resolve (/Users/owner/.atom/packages/prettier-atom/node_modules/require-relative/index.js:30:17)
at getModulePath (/Users/owner/.atom/packages/prettier-atom/node_modules/prettier-eslint/dist/index.js:254:38)
...
prettier-atom 0.51.0
This seems to be because prettier is looking for the eslint module which has been deprecated and can't now be installed, instead of the linter-eslint module.
I can't figure out how to get prettier to look for the correct module though