Remove GB from EU tax rules, can still be added back manually with addRateForCountry()

Fix #25

Author: spaze

README.md

@@ -167,6 +167,7 @@ The returned array of rates is unsorted. This method can be useful when you want
 
 EU countries are supported as well as some non-EU countries that use VAT. Some countries are not supported even though they also have VAT. Currently, that's the case for the following countries:
 - Switzerland (CH)
+- United Kingdom (GB)
 - Norway (NO)
 - Turkey (TR)
 

src/VatRates.php

@@ -95,14 +95,6 @@ class VatRates
 				'Mayotte' => 0,
 			],
 		],
-		'GB' => [ // United Kingdom
-			'rate' => 0.20,
-			'exceptions' => [
-				// UK RAF Bases in Cyprus are taxed at Cyprus rate
-				'Akrotiri' => 0.19,
-				'Dhekelia' => 0.19,
-			],
-		],
 		'GR' => [ // Greece
 			'rate' => 0.24,
 			'exceptions' => [
@@ -200,6 +192,14 @@ class VatRates
 				self::LOW => 0.025,
 			],
 		],
+		'GB' => [ // United Kingdom
+			'rate' => 0.20,
+			'exceptions' => [
+				// UK RAF Bases in Cyprus are taxed at Cyprus rate
+				'Akrotiri' => 0.19,
+				'Dhekelia' => 0.19,
+			],
+		],
 		'NO' => [ // Norway
 			'rate' => 0.25,
 		],
@@ -311,18 +311,6 @@ class VatRates
 				'name' => 'Mayotte',
 			],
 		],
-		'GB' => [
-			// Akrotiri
-			[
-				'postalCode' => '/^BFPO57|BF12AT$/',
-				'code' => 'CY',
-			],
-			// Dhekelia
-			[
-				'postalCode' => '/^BFPO58|BF12AU$/',
-				'code' => 'CY',
-			],
-		],
 		'GR' => [
 			[
 				'postalCode' => '/^63086$/',
@@ -358,6 +346,29 @@ class VatRates
 		],
 	];
 
+	/**
+	 * Optional postal code exceptions.
+	 *
+	 * Non-EU countries with their own VAT requirements and postal code exceptions,
+	 * added with `addRateForCountry()` for the rate and the exceptions to be applied.
+	 *
+	 * @var array<string, array>
+	 */
+	private $optionalPostalCodeExceptions = [
+		'GB' => [
+			// Akrotiri
+			[
+				'postalCode' => '/^BFPO57|BF12AT$/',
+				'code' => 'CY',
+			],
+			// Dhekelia
+			[
+				'postalCode' => '/^BFPO58|BF12AU$/',
+				'code' => 'CY',
+			],
+		],
+	];
+
 	/** @var DateTimeImmutable */
 	private $now;
 
@@ -379,6 +390,9 @@ public function addRateForCountry(string $country): void
 			throw new NoVatRulesForCountryException("No optional tax rules specified for {$country}");
 		}
 		$this->taxRules[$country] = $this->optionalTaxRules[$country];
+		if (isset($this->optionalPostalCodeExceptions[$country])) {
+			$this->postalCodeExceptions[$country] = $this->optionalPostalCodeExceptions[$country];
+		}
 	}
 
 

tests/VatCalculatorTest.php

@@ -235,6 +235,35 @@ public function testAddNonEuRateShouldCollectValidateThrows(): void
 	}
 
 
+	public function testAddGbRateShouldCollectWithPostalCodeException(): void
+	{
+		$this->assertFalse($this->vatCalculator->shouldCollectVat('GB'));
+		$this->assertFalse($this->vatCalculator->shouldCollectEuVat('GB'));
+		$result = $this->vatCalculator->calculate(24.00, 'GB', null, true);
+		$this->assertEquals(24.00, $result->getPrice());
+		$this->assertEquals(0.00, $result->getTaxRate());
+		$this->assertEquals(0.00, $result->getTaxValue());
+
+		$this->vatRates->addRateForCountry('GB');
+		$this->assertTrue($this->vatCalculator->shouldCollectVat('GB'));
+		$this->assertFalse($this->vatCalculator->shouldCollectEuVat('GB'));
+
+		// Valid UK post code
+		$postalCode = 'S1A 2AA';
+		$result = $this->vatCalculator->calculate(24.00, 'GB', $postalCode, false);
+		//Expect standard rate for UK
+		$this->assertEquals(28.80, $result->getPrice());
+		$this->assertEquals(0.20, $result->getTaxRate());
+		$this->assertEquals(4.80, $result->getTaxValue());
+
+		$postalCode = 'BFPO58'; // Dhekelia
+		$result = $this->vatCalculator->calculate(24.00, 'GB', $postalCode, false);
+		$this->assertEquals(28.56, $result->getPrice());
+		$this->assertEquals(0.19, $result->getTaxRate());
+		$this->assertEquals(4.56, $result->getTaxValue());
+	}
+
+
 	public function testSetBusinessCountryCode(): void
 	{
 		$this->vatCalculator->setBusinessCountryCode('DE');
@@ -265,12 +294,6 @@ public function testChecksPostalCodeForVatExceptions(): void
 		$this->assertEquals(0.19, $result->getTaxRate());
 		$this->assertEquals(4.56, $result->getTaxValue());
 
-		$postalCode = 'BFPO58'; // Dhekelia
-		$result = $this->vatCalculator->calculate(24.00, 'GB', $postalCode, false);
-		$this->assertEquals(28.56, $result->getPrice());
-		$this->assertEquals(0.19, $result->getTaxRate());
-		$this->assertEquals(4.56, $result->getTaxValue());
-
 		$postalCode = '9122'; // Madeira
 		$result = $this->vatCalculator->calculate(24.00, 'PT', $postalCode, false);
 		$this->assertEquals(29.28, $result->getPrice());
@@ -288,14 +311,6 @@ public function testPostalCodesWithoutExceptionsGetStandardRate(): void
 		$this->assertEquals(29.04, $result->getPrice());
 		$this->assertEquals(0.21, $result->getTaxRate());
 		$this->assertEquals(5.04, $result->getTaxValue());
-
-		// Valid UK post code
-		$postalCode = 'S1A 2AA';
-		$result = $this->vatCalculator->calculate(24.00, 'GB', $postalCode, false);
-		//Expect standard rate for UK
-		$this->assertEquals(28.80, $result->getPrice());
-		$this->assertEquals(0.20, $result->getTaxRate());
-		$this->assertEquals(4.80, $result->getTaxValue());
 	}