refactor ExceptionTest and add a couple more test cases

Author: robocoder

tests/ExceptionTest.php

@@ -7,27 +7,60 @@ public function setUp() {
 		$this->scss = new scssc();
 	}
 
-	public function compile($str) {
-		return trim($this->scss->compile($str));
+	/**
+	 * @param string $scss
+	 * @param string $expectedExceptionMessage
+	 *
+	 * @dataProvider provideScss
+	 */
+	public function testThrowError($scss, $expectedExceptionMessage) {
+		try {
+			$this->compile($scss);
+		} catch (Exception $e) {
+			if (strpos($e->getMessage(), $expectedExceptionMessage) !== false) {
+				return;
+			};
+		}
+
+		$this->fail('Expected exception to be raised: ' . $expectedExceptionMessage);
 	}
 
-	public function testMixinUnusedArgs() {
-		try {
-			$output = $this->compile(<<<END_OF_SCSS
+	/**
+	 * @return array
+	 */
+	public function provideScss() {
+		return array(
+			array(<<<END_OF_SCSS
+.test {
+  @include foo();
+}
+END_OF_SCSS
+,
+				'Undefined mixin foo'
+			),
+			array(<<<END_OF_SCSS
 @mixin do-nothing() {
 }
 
 .test {
   @include do-nothing(\$a: "hello");
 }
 END_OF_SCSS
-			);
-		} catch (Exception $e) {
-			if (strpos($e->getMessage(), 'Mixin or function doesn\'t have an argument named $a.') !== false) {
-				return;
-			};
-		}
+,
+				'Mixin or function doesn\'t have an argument named $a.'
+			),
+			array(<<<END_OF_SCSS
+div {
+  color: darken(cobaltgreen, 10%);
+}
+END_OF_SCSS
+,
+				'expecting color'
+			),
+		);
+	}
 
-		$this->fail('Expected exception to be raised');
+	private function compile($str) {
+		return trim($this->scss->compile($str));
 	}
 }