test: add generate-mixed-colors test

functions/_colors.scss

@@ -3,6 +3,11 @@
 @use "sass:math";
 @use "sass:string";
 
+@use './type-checking' as check;
+
+@use '../node_modules/sass-true/sass/throw' as throw;
+$_is-test: false !default;
+
 /// Convert HEX colors to R, G, B values
 /// @param {Color} $color
 /// @return {String}
@@ -106,11 +111,26 @@
 	$steps: 20,
 	$color2-peak: 11,
 ) {
+	@if(check.is-color($color1) == false) {
+		@return throw.error("❌  ===> The color1 parameter must be a color.", $catch: $_is-test);
+	}
+	@if(check.is-color($color2) == false) {
+		@return throw.error("❌  ===> The color2 parameter must be a color.", $catch: $_is-test);
+	}
+	@if(check.is-color($color3) == false) {
+		@return throw.error("❌  ===> The color3 parameter must be a color.", $catch: $_is-test);
+	}
+	@if(check.is-integer($steps) == false) {
+		@return throw.error("❌  ===> The steps parameter must be an integer.", $catch: $_is-test);
+	}
+	@if(check.is-integer($color2-peak) == false) {
+		@return throw.error("❌  ===> The color2-peak parameter must be an integer.", $catch: $_is-test);
+	}
 	@if ($color2-peak > $steps) {
-		@error "The peak point for color2 must be less than or equal to the number of steps.";
+		@return throw.error("❌  ===> The peak point for color2 must be less than or equal to the number of steps.", $catch: $_is-test);
 	}
 	@if ($color2-peak < 1) {
-		@error "The peak point for color2 must be greater than or equal to 1.";
+		@return throw.error("❌  ===> The peak point for color2 must be greater than or equal to 1.", $catch: $_is-test);
 	}
 
 	$colorMap: (1: $color1);

functions/_type-checking.scss

@@ -126,3 +126,12 @@
 	@return is-length($value) or is-percentage($value) or
 		list.index('top' 'right' 'bottom' 'left' 'center', $value) != null;
 }
+
+/// Check if its a color value
+/// @param {Void} $value - Value to check
+/// @group Type-Checking
+/// @author https://github.com/red-freak
+/// @since v2.5.0
+@function is-color($value) {
+	@return meta.type-of($value) == 'color';
+}

tests/colors-generate-mixed-colors.spec.scss

@@ -0,0 +1,48 @@
+//@use 'true';
+$_is-test: true;
+@use '../node_modules/sass-true/sass/true' as true;
+@import '../functions/_colors.scss';
+
+
+@include true.describe('generate-mixed-colors()') {
+	@include true.it('should throw an error if the step and peak parameters are wrong') {
+		@include true.assert-equal(
+			generate-mixed-colors(1, 1, 1), 'ERROR: ❌  ===> The color1 parameter must be a color.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, 1, 1), 'ERROR: ❌  ===> The color2 parameter must be a color.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, 1), 'ERROR: ❌  ===> The color3 parameter must be a color.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, "hallo"), 'ERROR: ❌  ===> The steps parameter must be an integer.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 10, "welt"), 'ERROR: ❌  ===> The color2-peak parameter must be an integer.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 0, 2), 'ERROR: ❌  ===> The peak point for color2 must be less than or equal to the number of steps.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 0, 0), 'ERROR: ❌  ===> The peak point for color2 must be greater than or equal to 1.'
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, -1, -1), 'ERROR: ❌  ===> The peak point for color2 must be greater than or equal to 1.'
+		);
+	}
+	@include true.it('should return expected color maps') {
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 1, 1), (1: yellow)
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 3, 2), (1: green, 2: yellow, 3: red)
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red, 2, 1), (1: yellow, 2: red)
+		);
+		@include true.assert-equal(
+			generate-mixed-colors(green, yellow, red), (1: green, 2: #2e9700, 3: #46a300, 4: #5dae00, 5: #74ba00, 6: #8bc500, 7: #a2d100, 8: #b9dc00, 9: #d1e800, 10: #e8f300, 11: yellow, 12: #ffe300, 13: #ffc600, 14: #ffaa00, 15: #ff8e00, 16: #ff7100, 17: #ff5500, 18: #ff3900, 19: #ff1c00, 20: red)
+		);
+	}
+}