Unit Testing -- UI Example - Revision history

Radiant tech: added Testing and Bug Squad categories

2011-12-15T19:54:58Z

added Testing and Bug Squad categories

Instance: /* Testing User Interface Code */

2008-06-24T23:04:20Z

‎Testing User Interface Code

Instance: Page created.

2008-06-24T23:03:50Z

Page created.

Instance: Timeout defense.

2008-06-24T22:29:11Z

Timeout defense.

New page

== Testing User Interface Code ==
This expands on the basics given in the [[Unit_Testing_--_a_Simple_Example|Simple Example]]. In this example, we want to test a class that outputs code to the browser.

PHPUnit has an extension to support this, but it's pretty limited. You can extend your test class from PHPUnit_Extensions_OutputTestCase, and then use assertions like $this->expectOutputString('foo') and $this -> expectOutputRegex($regex) to verify that the output contains the string you're looking for. That technique works for simple cases, but if the method you want to test takes complex parameters or generates a lot of code, it's just not enough.

=== Capturing Output ===
This snippet from a test demonstrates the method for capturing data.
<source lang="php">
ob_start();
HTML_modules::add($modules, $this -> client);
$result = ob_get_flush();
</source>
The $result now variable has everything that would normally go to the browser.

=== Verifying the Output ===
Now that we have the output, how do we make sure it is "correct"?

In this example, there are two defining characteristics to the output: each module should be rendered as a radio button and a link. Let's look for the radio buttons first.
<source lang="php">
// Get contents of all radio buttons
preg_match_all('|<input .*type="radio".*>|U', $result, $matches);
// Filter for name=module
foreach ($matches[0] as $index => $subs) {
if (strpos($subs, 'name="module"') === false) {
unset($matches[0][$index]);
}
}
$this -> assertEquals(count($modules), count($matches[0]), 'Number of radio buttons.');
</source>

← Older revision		Revision as of 19:54, 15 December 2011
Line 92:		Line 92:

	Return to [[Unit_Testing\|Unit Testing]]		Return to [[Unit_Testing\|Unit Testing]]
		+
		+	[[Category:Testing]][[Category:Bug Squad]]

@@ Line 4: / Line 4: @@
 PHPUnit has an extension to support this, but it's pretty limited. You can extend your test class from PHPUnit_Extensions_OutputTestCase, and then use assertions like $this->expectOutputString('foo') and $this -> expectOutputRegex($regex) to verify that the output contains the string you're looking for. That technique works for simple cases, but if the method you want to test takes complex parameters or generates a lot of code, it's just not enough.
-This example is based on /unittest/tests/administrator/components/com_modules/HTML_modules-0000-add-test.php. You will need to refer to the full test and understand [[Unit_testing_Mock_Objects|mock objects]] in order to get a complete understanding of what is involved.
+This example is based on /unittest/tests/administrator/components/com_modules/HTML_modules-0000-add-test.php. You will need to refer to the full test and understand [[Unit_Testing_Mock_Objects|mock objects]] in order to get a complete understanding of what is involved.
 === Capturing Output ===

@@ Line 3: / Line 3: @@
 PHPUnit has an extension to support this, but it's pretty limited. You can extend your test class from PHPUnit_Extensions_OutputTestCase, and then use assertions like $this->expectOutputString('foo') and $this -> expectOutputRegex($regex) to verify that the output contains the string you're looking for. That technique works for simple cases, but if the method you want to test takes complex parameters or generates a lot of code, it's just not enough.
 === Capturing Output ===
-This snippet from a test demonstrates the method for capturing data.
+This snippet from the test demonstrates the method for capturing data.
 <source lang="php">
 ob_start();
@@ Line 11: / Line 13: @@
 $result = ob_get_flush();
 </source>
-The $result now variable has everything that would normally go to the browser.
+The $result variable now has everything that would normally go to the browser. Note that PHP in command line mode may also dump all the output to the console. This is irritating but harmless.
 === Verifying the Output ===
-Now that we have the output, how do we make sure it is "correct"?
+Now that we have captured the output, how do we make sure it is "correct"?
 In this example, there are two defining characteristics to the output: each module should be rendered as a radio button and a link. Let's look for the radio buttons first.
 <source lang="php">
-		// Get contents of all radio buttons
+// Get contents of all radio buttons
-		preg_match_all('|<input .*type="radio".*>|U', $result, $matches);
+preg_match_all('|<input .*type="radio".*>|U', $result, $matches);
-		// Filter for name=module
+// Filter for name=module
-		foreach ($matches[0] as $index => $subs) {
+foreach ($matches[0] as $index => $subs) {
-			if (strpos($subs, 'name="module"') === false) {
+    if (strpos($subs, 'name="module"') === false) {
-				unset($matches[0][$index]);
+        unset($matches[0][$index]);
-−
+    }
-−
+}
-		$this -> assertEquals(count($modules), count($matches[0]), 'Number of radio buttons.');
+$this -> assertEquals(count($modules), count($matches[0]), 'Number of radio buttons.');
 </source>