Use of strict-boolean-expressions
Opened this issue · 7 comments
The configuration of tslint: strict-boolean-expressions
currently prevents using short-circuit evaluation in assignment as per Airbnb's 15.7 no-unneeded-ternary
:
This type is not allowed in the operand for the '||' operator because it is always truthy.
There's an issue palantir/tslint#3279 concerning the application of strict-boolean-expressions
in different contexts that will hopefully allow excluding assignments - which would support loosening the rule to support compliance with no-unneeded-ternary
.
Meanwhile there is no ideal setting, but I've currently overridden the rule to the following:
"strict-boolean-expressions": [
true,
"allow-null-union",
"allow-undefined-union",
"allow-string",
"allow-mix"
]
It's not ideal... 😐 but helps compliance with 15.7 for string building and assignment (at the cost of compliance with 15.3), while not allowing numbers prevents using array length without a comparison which seems to be the most common violation of 15.3 at the cost of excluding use of numbers in logical assignment.
I appreciate there are a lot of inconsistencies with the eslint
implementation due largely to rule availability and differing coding standards - so mainly just flagging the open tslint
issue and more generally interested in your thoughts?
I think the ruleset shouldn't to limit the style guide.
So I think your rule is good and I think current ruleset should be fixed.
If the preference is to make the rule set permissive wherever it might limit adherence to the style guide, at the cost of enforcing strictness elsewhere maybe "allow-number"
should also be added to the mix of allowed boolean expressions.
Unfortunately using inline constant strings currently doesn't comply:
let a = foo || 'bar';
🚫
...but you can cast to a string to satisfy the linter like so:
let a = foo || 'bar' as string;
🤢 😕
Being more permissive the rule change won't break anyone's linting now - but might catch some out later if restored to be more restrictive in the right contexts for cases of 15.3
I look like it is possible without as-cast....?
Disable the rule completely? I guess that fits with the permissive approach...
Revisit once palantir/tslint#3279 is resolved.
I thought it can release without wait for palantir/tslint#3279. I released it as 5.6.0.
I'll keep watching the issue.
I look like it is possible without as-cast....?
When I tried it today, the error was displayed.
It seems this tslint's issue isn't easily fixed. I have no idea when it will be fixed, so I thought it should be disabled.
"strict-boolean-expressions": false
The rule was removed.
It is going to be reverted when tslint's issue is fixed.