Support message placeholders for error messages

ESLinst’s context.report is the API used to report linting validations (similar to ember-template-eslint’s log method). context.report’s argument accepts an optional data object to be used to provide values for placeholders in messages.

This is useful when a rule provides a default error message and the opportunity to customize such error message. Using placeholders users are still able to add information that are only available at runtime to their custom error message making it more useful and understandable.

My suggestion would be to update log’s input object to support a similar format of message and placeholders.

Any thoughts?

Sample implementation

https://github.com/ember-template-lint/ember-template-lint/pull/1926

References

• logic that applies interpolation in ESLint;
• interpolate function.

[rwjblue]

@ventuno - Can you give more context around when you’d be using these placeholders? As I mentioned before, if you are planning to author new rules and use this system I see no benefit at all over using template strings in the original source. However, based on your last comment, it seems like you are trying to override the built-in rule’s messages? How do you plan on doing that? For example, I don’t think subclassing of the built-in rules is something that we support.

[rwjblue]

AHA! OK, that was a really important missing piece. I totally did not understand that you meant you wanted to customize the message on the configuration side (I had previously thought that you wanted to do this when you were authoring a rule, at which point I legitimately think that template strings are much better).