Assigned constructor field parameter

Reports a common mistake in TypeScript code, when a class field is declared as a constructor parameter, and then this parameter is assigned.

In this case, the corresponding field won't be assigned, only the local parameter value is modified.

class Foo {
  constructor(private p: number) {
    p = 1; //must be this.p = 1;
  }
}

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

TypeScriptSuspiciousConstructorParameterAssignment

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | JavaScript and TypeScript | TypeScript

Inspection ID: TypeScriptSuspiciousConstructorParameterAssignment

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection TypeScriptSuspiciousConstructorParameterAssignment

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

Inspection Details
By default bundled with:	CLion 2025.2, GoLand 2025.2, IntelliJ IDEA 2025.2, JetBrains Rider 2025.2, PhpStorm 2025.2, PyCharm 2025.2, Qodana for .NET 2025.2, Qodana for Go 2025.2, Qodana for JS 2025.2, Qodana for JVM 2025.2, Qodana for PHP 2025.2, Qodana for Ruby 2025.2, RubyMine 2025.2, WebStorm 2025.2

Last modified: 18 September 2025