InvalidToString

An object is used where a string is expected (e.g., string concatenation, echo, or string interpolation), but the object’s class does not implement the __toString method. This produces a fatal error in PHP.

Example

<?php
class Point {
    public function __construct(
        public float $x,
        public float $y,
    ) {}
}

$p = new Point(1.0, 2.0);
echo "Point: " . $p; // Point has no __toString method

How to fix

Add a __toString method to the class, or explicitly convert the object to a string before use:

<?php
class Point {
    public function __construct(
        public float $x,
        public float $y,
    ) {}

    public function __toString(): string {
        return "({$this->x}, {$this->y})";
    }
}