diff --git a/tests/math_expression.test b/tests/math_expression.test
index 730e079..9f9f4c2 100644
--- a/tests/math_expression.test
+++ b/tests/math_expression.test
@@ -39,31 +39,31 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase {
     $math_expression = new ctools_math_expr();
 
     // Test constant expressions.
-    $this->assertEqual($math_expression->e('2'), 2);
+    $this->assertEqual($math_expression->evaluate('2'), 2);
     $random_number = rand(0, 10);
-    $this->assertEqual($random_number, $math_expression->e((string) $random_number));
+    $this->assertEqual($random_number, $math_expression->evaluate((string) $random_number));
 
     // Test simple arithmetic.
     $random_number_a = rand(5, 10);
     $random_number_b = rand(5, 10);
-    $this->assertEqual($random_number_a + $random_number_b, $math_expression->e("$random_number_a + $random_number_b"));
-    $this->assertEqual($random_number_a - $random_number_b, $math_expression->e("$random_number_a - $random_number_b"));
-    $this->assertEqual($random_number_a * $random_number_b, $math_expression->e("$random_number_a * $random_number_b"));
-    $this->assertEqual($random_number_a / $random_number_b, $math_expression->e("$random_number_a / $random_number_b"));
+    $this->assertEqual($random_number_a + $random_number_b, $math_expression->evaluate("$random_number_a + $random_number_b"));
+    $this->assertEqual($random_number_a - $random_number_b, $math_expression->evaluate("$random_number_a - $random_number_b"));
+    $this->assertEqual($random_number_a * $random_number_b, $math_expression->evaluate("$random_number_a * $random_number_b"));
+    $this->assertEqual(round($random_number_a / $random_number_b, 8), round($math_expression->evaluate("$random_number_a / $random_number_b"), 8));
 
     // Test Associative property.
     $random_number_c = rand(5, 10);
-    $this->assertEqual($math_expression->e("$random_number_a + ($random_number_b + $random_number_c)"), $math_expression->e("($random_number_a + $random_number_b) + $random_number_c"));
-    $this->assertEqual($math_expression->e("$random_number_a * ($random_number_b * $random_number_c)"), $math_expression->e("($random_number_a * $random_number_b) * $random_number_c"));
+    $this->assertEqual($math_expression->evaluate("$random_number_a + ($random_number_b + $random_number_c)"), $math_expression->evaluate("($random_number_a + $random_number_b) + $random_number_c"));
+    $this->assertEqual($math_expression->evaluate("$random_number_a * ($random_number_b * $random_number_c)"), $math_expression->evaluate("($random_number_a * $random_number_b) * $random_number_c"));
 
     // Test Commutative property.
-    $this->assertEqual($math_expression->e("$random_number_a + $random_number_b"), $math_expression->e("$random_number_b + $random_number_a"));
-    $this->assertEqual($math_expression->e("$random_number_a * $random_number_b"), $math_expression->e("$random_number_b * $random_number_a"));
+    $this->assertEqual($math_expression->evaluate("$random_number_a + $random_number_b"), $math_expression->evaluate("$random_number_b + $random_number_a"));
+    $this->assertEqual($math_expression->evaluate("$random_number_a * $random_number_b"), $math_expression->evaluate("$random_number_b * $random_number_a"));
 
     // Test Distributive property.
-    $this->assertEqual($math_expression->e("($random_number_a + $random_number_b) * $random_number_c"), $math_expression->e("($random_number_a * $random_number_c + $random_number_b * $random_number_c)"));
+    $this->assertEqual($math_expression->evaluate("($random_number_a + $random_number_b) * $random_number_c"), $math_expression->evaluate("($random_number_a * $random_number_c + $random_number_b * $random_number_c)"));
 
-    $this->assertEqual(pow($random_number_a, $random_number_b), $math_expression->e("$random_number_a ^ $random_number_b"));
+    $this->assertEqual(pow($random_number_a, $random_number_b), $math_expression->evaluate("$random_number_a ^ $random_number_b"));
   }
 
   public function testBuildInFunctions() {
@@ -72,26 +72,25 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase {
     // @todo: maybe run this code multiple times to test different values.
     $random_double = $this->rand01();
     $random_int = rand(5, 10);
-    $this->assertFloat(sin($random_double), $math_expression->e("sin($random_double)"));
-    $this->assertFloat(cos($random_double), $math_expression->e("cos($random_double)"));
-    $this->assertFloat(tan($random_double), $math_expression->e("tan($random_double)"));
-    $this->assertFloat(exp($random_double), $math_expression->e("exp($random_double)"));
-    $this->assertFloat(sqrt($random_double), $math_expression->e("sqrt($random_double)"));
-    $this->assertFloat(log($random_double), $math_expression->e("ln($random_double)"));
-    $this->assertFloat(round($random_double), $math_expression->e("round($random_double)"));
-    $this->assertFloat(abs($random_double + $random_int), $math_expression->e('abs(' . ($random_double + $random_int) . ')'));
-    $this->assertEqual(round($random_double + $random_int), $math_expression->e('round(' . ($random_double + $random_int) . ')'));
-    $this->assertEqual(ceil($random_double + $random_int), $math_expression->e('ceil(' . ($random_double + $random_int) . ')'));
-    $this->assertEqual(floor($random_double + $random_int), $math_expression->e('floor(' . ($random_double + $random_int) . ')'));
+    $this->assertFloat(sin($random_double), $math_expression->evaluate("sin($random_double)"));
+    $this->assertFloat(cos($random_double), $math_expression->evaluate("cos($random_double)"));
+    $this->assertFloat(tan($random_double), $math_expression->evaluate("tan($random_double)"));
+    $this->assertFloat(exp($random_double), $math_expression->evaluate("exp($random_double)"));
+    $this->assertFloat(sqrt($random_double), $math_expression->evaluate("sqrt($random_double)"));
+    $this->assertFloat(log($random_double), $math_expression->evaluate("ln($random_double)"));
+    $this->assertFloat(round($random_double), $math_expression->evaluate("round($random_double)"));
+    $this->assertFloat(abs($random_double + $random_int), $math_expression->evaluate('abs(' . ($random_double + $random_int) . ')'));
+    $this->assertEqual(round($random_double + $random_int), $math_expression->evaluate('round(' . ($random_double + $random_int) . ')'));
+    $this->assertEqual(ceil($random_double + $random_int), $math_expression->evaluate('ceil(' . ($random_double + $random_int) . ')'));
+    $this->assertEqual(floor($random_double + $random_int), $math_expression->evaluate('floor(' . ($random_double + $random_int) . ')'));
 
     // @fixme: you can't run time without an argument.
-    $this->assertFloat(time(), $math_expression->e('time(1)'));
+    $this->assertFloat(time(), $math_expression->evaluate('time(1)'));
 
     $random_double_a = $this->rand01();
     $random_double_b = $this->rand01();
-    // @fixme: max/min don't work at the moment.
-//    $this->assertFloat(max($random_double_a, $random_double_b), $math_expression->e("max($random_double_a, $random_double_b)"));
-//    $this->assertFloat(min($random_double_a, $random_double_b), $math_expression->e("min($random_double_a, $random_double_b)"));
+    $this->assertFloat(max($random_double_a, $random_double_b), $math_expression->evaluate("max($random_double_a, $random_double_b)"));
+    $this->assertFloat(min($random_double_a, $random_double_b), $math_expression->evaluate("min($random_double_a, $random_double_b)"));
   }
 
   public function testVariables() {
@@ -101,11 +100,11 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase {
     $random_number_b = rand(5, 10);
 
     // Store the first random number and use it on calculations.
-    $math_expression->e("var = $random_number_a");
-    $this->assertEqual($random_number_a + $random_number_b, $math_expression->e("var + $random_number_b"));
-    $this->assertEqual($random_number_a * $random_number_b, $math_expression->e("var * $random_number_b"));
-    $this->assertEqual($random_number_a - $random_number_b, $math_expression->e("var - $random_number_b"));
-    $this->assertEqual($random_number_a / $random_number_b, $math_expression->e("var / $random_number_b"));
+    $math_expression->evaluate("var = $random_number_a");
+    $this->assertEqual($random_number_a + $random_number_b, $math_expression->evaluate("var + $random_number_b"));
+    $this->assertEqual($random_number_a * $random_number_b, $math_expression->evaluate("var * $random_number_b"));
+    $this->assertEqual($random_number_a - $random_number_b, $math_expression->evaluate("var - $random_number_b"));
+    $this->assertEqual(round($random_number_a / $random_number_b, 8), round($math_expression->evaluate("var / $random_number_b"), 8));
   }
 
   public function testCustomFunctions() {
@@ -115,15 +114,31 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase {
     $random_number_b = rand(5, 10);
 
     // Create a one-argument function.
-    $math_expression->e("f(x) = 2 * x");
-    $this->assertEqual($random_number_a * 2, $math_expression->e("f($random_number_a)"));
-    $this->assertEqual($random_number_b * 2, $math_expression->e("f($random_number_b)"));
+    $math_expression->evaluate("f(x) = 2 * x");
+    $this->assertEqual($random_number_a * 2, $math_expression->evaluate("f($random_number_a)"));
+    $this->assertEqual($random_number_b * 2, $math_expression->evaluate("f($random_number_b)"));
 
     // Create a two-argument function.
-    $math_expression->e("g(x, y) = 2 * x + y");
-    $this->assertEqual($random_number_a * 2 + $random_number_b, $math_expression->e("g($random_number_a, $random_number_b)"));
+    $math_expression->evaluate("g(x, y) = 2 * x + y");
+    $this->assertEqual($random_number_a * 2 + $random_number_b, $math_expression->evaluate("g($random_number_a, $random_number_b)"));
 
     // Use a custom function in another function.
-    $this->assertEqual(($random_number_a * 2 + $random_number_b) * 2, $math_expression->e("f(g($random_number_a, $random_number_b))"));
+    $this->assertEqual(($random_number_a * 2 + $random_number_b) * 2, $math_expression->evaluate("f(g($random_number_a, $random_number_b))"));
   }
+
+  public function testIf() {
+    $math_expression = new ctools_math_expr();
+
+    $random_number_a = rand(1, 5);
+    $random_number_b = rand(10, 20);
+
+    $this->assertEqual($math_expression->evaluate("if(1, $random_number_a, $random_number_b)"), $random_number_a);
+    $this->assertEqual($math_expression->evaluate("if(1, $random_number_a)"), $random_number_a);
+
+    $this->assertEqual($math_expression->evaluate("if(0, $random_number_a, $random_number_b)"), $random_number_b);
+
+    // Also add an expression so ensure it's evaluated.
+    $this->assertEqual($math_expression->evaluate("if($random_number_a > $random_number_b, $random_number_a, $random_number_b)"), $random_number_a);
+  }
+
 }