Add unicorn/string-content rule

[sindresorhus]

See: https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/string-content.md

Anything else useful we can enforce in strings?

// @pvdlg @fregante

[fregante]

I’m unsure. Would this rule require exceptions every time ... on Commit is used in a GraphQL query? Could it use tags to automatically determine code strings to skip?

gql` repo() { ... on Commit {}}`

[sindresorhus]

I think the rule should be excluded on gql by default as it's code in a string and not a pure string.

// @fisker

[sindresorhus]

@fregante The rule has ' => ’ built-in. Should we also do "foo" => “foo”? The complication is that the changed quotes are different characters for left and right.

[fregante]

I think this rule is something not all projects can handle by default. CSS selectors have lots of " and '. Let's start with ' for now

[isghe]

It's really dangerous; it breaks a program I am working on:
from:

'readMessage(:queue, :id, \'ZCP\', :cursor)';

to

'readMessage(:queue, :id, ’ZCP’, :cursor)';

breaking a query to oracle db.

I think it shouldn't change the content of a string.

[tusbar]

Agreed, this rule should be reverted as it breaks any string that’s not displayable text.

[niftylettuce]

Agreed, same exact thing happened on my end that @isghe experienced.

[niftylettuce]

Please resolve this, I'm seeing stuff like this get replaced as well:

package-scripts.js (nps)

-pretestMongo: "mongo forwardemail_test --eval 'db.dropDatabase()'",
+pretestMongo: 'mongo forwardemail_test --eval ’db.dropDatabase()’',