[BUGFIX] Don't render rgb colors with % values as hex (#803)

The only percentage values that could be reliably converted to hex notation are
0%, 20%, 40%, etc.
It's beyond the scope of this library to do that.

Also add additional tests to confirm parsing of percentage values.
Some of these are commented out,
because the input data would result in rendering in an invalid format.
(The "legacy" syntax does not allow a mixture of `percentage`s and `number`s,
so it would be necessary to implement rendering in the "modern" syntax
to resolve those cases, which is beyond the scope of this PR.)

Co-authored-by: Jake Hotson <[email protected]>

Author: JakeQZ

CHANGELOG.md

@@ -45,6 +45,7 @@ Please also have a look at our
 
 ### Fixed
 
+- Don't render `rgb` colors with percentage values using hex notation (#803)
 - Parse `@font-face` `src` property as comma-delimited list (#790)
 - Fix type errors in PHP strict mode (#664)
 - Fix undefined local variable in `CalcFunction::parse()` (#593)

src/Value/Color.php

@@ -225,7 +225,11 @@ public function __toString(): string
     public function render(OutputFormat $outputFormat): string
     {
         // Shorthand RGB color values
-        if ($outputFormat->getRGBHashNotation() && \implode('', \array_keys($this->aComponents)) === 'rgb') {
+        if (
+            $outputFormat->getRGBHashNotation()
+            && \implode('', \array_keys($this->aComponents)) === 'rgb'
+            && $this->allComponentsAreNumbers()
+        ) {
             $result = \sprintf(
                 '%02x%02x%02x',
                 $this->aComponents['r']->getSize(),
@@ -237,4 +241,19 @@ public function render(OutputFormat $outputFormat): string
         }
         return parent::render($outputFormat);
     }
+
+    /**
+     * Test whether all color components are absolute numbers (CSS type `number`), not percentages or anything else.
+     * If any component is not an instance of `Size`, the method will also return `false`.
+     */
+    private function allComponentsAreNumbers(): bool
+    {
+        foreach ($this->aComponents as $component) {
+            if (!$component instanceof Size || $component->getUnit() !== null) {
+                return false;
+            }
+        }
+
+        return true;
+    }
 }

tests/Unit/Value/ColorTest.php

@@ -54,6 +54,10 @@ public static function provideValidColorAndExpectedRendering(): array
                 'rgb(0, 118, 0)',
                 '#007600',
             ],
+            'legacy rgb with percentage components' => [
+                'rgb(0%, 60%, 0%)',
+                'rgb(0%,60%,0%)',
+            ],
             'legacy rgba with fractional alpha' => [
                 'rgba(0, 119, 0, 0.5)',
                 'rgba(0,119,0,.5)',
@@ -62,6 +66,14 @@ public static function provideValidColorAndExpectedRendering(): array
                 'rgba(0, 119, 0, 50%)',
                 'rgba(0,119,0,50%)',
             ],
+            'legacy rgba with percentage components and fractional alpha' => [
+                'rgba(0%, 60%, 0%, 0.5)',
+                'rgba(0%,60%,0%,.5)',
+            ],
+            'legacy rgba with percentage components and percentage alpha' => [
+                'rgba(0%, 60%, 0%, 50%)',
+                'rgba(0%,60%,0%,50%)',
+            ],
             'legacy rgb as rgba' => [
                 'rgba(0, 119, 0)',
                 '#070',
@@ -74,16 +86,73 @@ public static function provideValidColorAndExpectedRendering(): array
                 'rgb(0 119 0)',
                 '#070',
             ],
+            // The "legacy" syntax currently used for rendering does not allow a mixture of percentages and numbers.
+            /*
+            'modern rgb with percentage R' => [
+                'rgb(0% 119 0)',
+                'rgb(0% 119 0)',
+            ],
+            'modern rgb with percentage G' => [
+                'rgb(0 60% 0)',
+                'rgb(0 60% 0)',
+            ],
+            'modern rgb with percentage B' => [
+                'rgb(0 119 0%)',
+                'rgb(0 119 0%)',
+            ],
+            'modern rgb with percentage R&G' => [
+                'rgb(0% 60% 0)',
+                'rgb(0% 60% 0)',
+            ],
+            'modern rgb with percentage R&B' => [
+                'rgb(0% 119 0%)',
+                'rgb(0% 119 0%)',
+            ],
+            'modern rgb with percentage G&B' => [
+                'rgb(0 60% 0%)',
+                'rgb(0 60% 0%)',
+            ],
+            //*/
+            'modern rgb with percentage components' => [
+                'rgb(0% 60% 0%)',
+                'rgb(0%,60%,0%)',
+            ],
             /*
             'modern rgb with none' => [
                 'rgb(none 119 0)',
                 'rgb(none 119 0)',
             ],
             //*/
-            'modern rgba' => [
+            'modern rgba with fractional alpha' => [
                 'rgb(0 119 0 / 0.5)',
                 'rgba(0,119,0,.5)',
             ],
+            'modern rgba with percentage alpha' => [
+                'rgb(0 119 0 / 50%)',
+                'rgba(0,119,0,50%)',
+            ],
+            /*
+            'modern rgba with percentage R' => [
+                'rgb(0% 119 0 / 0.5)',
+                'rgba(0% 119 0/.5)',
+            ],
+            'modern rgba with percentage G' => [
+                'rgb(0 60% 0 / 0.5)',
+                'rgba(0 60% 0/.5)',
+            ],
+            'modern rgba with percentage B' => [
+                'rgb(0 119 0% / 0.5)',
+                'rgba(0 119 0%/.5)',
+            ],
+            //*/
+            'modern rgba with percentage RGB' => [
+                'rgb(0% 60% 0% / 0.5)',
+                'rgba(0%,60%,0%,.5)',
+            ],
+            'modern rgba with percentage components' => [
+                'rgb(0% 60% 0% / 50%)',
+                'rgba(0%,60%,0%,50%)',
+            ],
             /*
             'modern rgba with none as alpha' => [
                 'rgb(0 119 0 / none)',