TypeError: Cannot read property 'length' of null

[Arcanemagus]

Got this stack trace from a report filed by @rickgregory over on linter-php:

TypeError: Cannot read property 'length' of null
    at SyncWriteStream.write (fs.js:1981:38)
    at Object.execFileSync (child_process.js:471:20)
    at pathFromShellSync (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/node_modules/consistent-path/node_modules/shell-path/index.js:52:28)
    at Function.module.exports.sync (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/node_modules/consistent-path/node_modules/shell-path/index.js:34:11)
    at findOutPath (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/node_modules/consistent-path/lib/index.js:27:62)
    at getPath (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/node_modules/consistent-path/lib/index.js:17:16)
    at _exec (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/lib/helpers.js:61:59)
    at Object.exec (/Users/rickg/.atom/packages/linter-php/node_modules/atom-linter/lib/helpers.js:152:10)

Is this a bug here, or somewhere deeper?

[steelbrain]

Opened here sindresorhus/shell-path#10