{"record":{"id":"4801a99a84d915fd","repo":"Intervention/image","slug":"the-channel-class-channel-does-not-exist","errorCode":null,"errorMessage":"The channel class \"{channel}\" does not exist","messagePattern":"The channel class \"(.+?)\" does not exist","errorType":"exception","errorClass":"Intervention\\Image\\Exceptions\\InvalidArgumentException","httpStatus":null,"severity":"error","filePath":"src/Colors/Palette.php","lineNumber":308,"sourceCode":"    }\n\n    /**\n     * {@inheritdoc}\n     *\n     * @see PaletteInterface::sortByChannel()\n     *\n     * @throws InvalidArgumentException\n     */\n    public function sortByChannel(string|ColorChannelInterface $channel): PaletteInterface\n    {\n        if ($this->bins === []) {\n            return $this;\n        }\n\n        // normalize to channel classname\n        $channel = is_string($channel) ? $channel : $channel::class;\n        if (!class_exists($channel)) {\n            throw new InvalidArgumentException(\n                'The channel class \"' . $channel . '\" does not exist',\n            );\n        }\n\n        $sortColorspace = match ($channel) {\n            Rgb\\Channels\\Red::class,\n            Rgb\\Channels\\Green::class,\n            Rgb\\Channels\\Blue::class,\n            Rgb\\Channels\\Alpha::class => Rgb\\Colorspace::class,\n            Cmyk\\Channels\\Cyan::class,\n            Cmyk\\Channels\\Magenta::class,\n            Cmyk\\Channels\\Yellow::class,\n            Cmyk\\Channels\\Key::class,\n            Cmyk\\Channels\\Alpha::class => Cmyk\\Colorspace::class,\n            Hsl\\Channels\\Hue::class,\n            Hsl\\Channels\\Saturation::class,\n            Hsl\\Channels\\Luminance::class,\n            Hsl\\Channels\\Alpha::class => Hsl\\Colorspace::class,","sourceCodeStart":290,"sourceCodeEnd":326,"githubUrl":"https://github.com/Intervention/image/blob/5598b9e39751c34afc5cdee84abef77f92c26f68/src/Colors/Palette.php#L290-L326","documentation":"Palette::sortByChannel() accepts either a channel object or a channel class-name string. When a string is passed, the library first runs class_exists($channel); if the string is not a loadable class (typo, missing namespace, wrong casing) it throws this InvalidArgumentException before any sorting happens. The same check guards sortByChannelDesc(), which delegates to sortByChannel().","triggerScenarios":"$palette->sortByChannel('Red') (short name without namespace), sortByChannel('Intervention\\Image\\Colors\\Rgb\\Chanels\\Red') (typo), or any dynamically built string that is not the fully-qualified name of a real channel class.","commonSituations":"Passing short channel names to avoid verbose imports; building the channel name from user input, config or database values; copy-pasting channel names between colorspaces (e.g. HSV 'Value' against an RGB palette).","solutions":["Pass a channel object taken from a color: $palette->sortByChannel($color->red())","Pass the ::class constant of a supported channel: sortByChannel(\\Intervention\\Image\\Colors\\Rgb\\Channels\\Red::class)","Add the missing use statement for the channel class and fix typos/casing in the string","Pre-check with class_exists($channel) before calling and reject unknown names early"],"exampleFix":"// before\n$palette->sortByChannel('Red');\n\n// after\nuse Intervention\\Image\\Colors\\Rgb\\Channels\\Red;\n$palette->sortByChannel(Red::class);","handlingStrategy":"validation","validationCode":"$channel = 'App\\Channels\\Red'; // or user input\nif (is_string($channel) && !class_exists($channel)) {\n    throw new \\InvalidArgumentException(\"Unknown channel class: {$channel}\");\n}\n$palette->sortByChannel($channel);","typeGuard":"function isChannelClass(string $channel): bool\n{\n    return class_exists($channel)\n        && is_subclass_of($channel, \\Intervention\\Image\\Interfaces\\ColorChannelInterface::class);\n}","tryCatchPattern":"try {\n    $palette->sortByChannel($channel);\n} catch (\\Intervention\\Image\\Exceptions\\InvalidArgumentException $e) {\n    // fall back to a known-good channel class\n    $palette->sortByChannel(\\Intervention\\Image\\Colors\\Rgb\\Channels\\Red::class);\n}","preventionTips":["Prefer passing channel objects such as $color->red() over class-name strings","Always use the ::class constant instead of hand-written class strings","Map user-supplied channel names to a whitelist of class names before calling"],"tags":["palette","sorting","color-channels","php"],"backgroundTag":"class-not-found","analyzedSha":"5598b9e39751c34afc5cdee84abef77f92c26f68","analyzedAt":"2026-08-23T02:17:31.068Z","schemaVersion":2},"datasetVersion":"2026-08-23T08:06:27.607Z"}