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nodePropertyInChecks

Disallows using the in operator to check properties on TypeScript nodes.

✅ This rule is included in the flint logical presets.

Using the in operator to check for the existence of properties on TypeScript AST nodes can lead to unreliable results, as not all properties may be present on every node type.

Examples

Section titled “Examples”
AE53< (sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4DCallExpressi1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#7FDBCA;--1:#096E">7253 node)< {d ivclassNa="meec-li">5<3}d ivclassNa="meco"><}d>
443F53 (4<4AE. spans="tyle--0:#7FDBCA;--1:#09">6E72344A3F53 Syntax4<4AE. spans="tyle--0:#7FDBCA;--1:#09">6E72CallExpres3F5<3) {divclass="Nameec-">3< {>

Options

Section titled “Options”

This rule is not configurable.

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”