composer init
kellyj/tddexample
Create src and tests directories.
Setup PSR-4 autoloading
"autoload": {
"psr-4": {
"Tdd\\": "src"
}
},
"autoload-dev": {
"psr-4": {
"Tdd\\Test\\": "tests"
}
},Create phpunit.xml file
<?xml version="1.0" encoding="UTF-8"?>
<phpunit bootstrap="vendor/autoload.php"
backupGlobals="false"
backupStaticAttributes="false"
colors="true"
verbose="true"
convertErrorsToExceptions="true"
convertNoticesToExceptions="true"
convertWarningsToExceptions="true"
processIsolation="false"
stopOnFailure="false">
<testsuites>
<testsuite name="Wrapper Test Suite">
<directory>tests</directory>
</testsuite>
</testsuites>
<filter>
<whitelist>
<directory suffix=".php">src/</directory>
</whitelist>
</filter>
</phpunit>$ composer require --dev phpunit/phpunit
composer.json:
"require-dev": {
"phpunit/phpunit": "^4.8"
}tests/Text/WrapperText.php
public function testCanCreateAWrapper()
{
$wrapper = new Wrapper();
$this->assertInstanceOf('\\Tdd\\Text\\Wrapper', $wrapper);
}What's the simplest?
What happens when I give it a blank string
public function testItShouldWrapAnEmptyString()
{
$wrapper = new Wrapper();
$this->assertEquals('', $wrapper->wrap(''));
}What's the next simplest?
What happens when I give it a string shorter than max chars?
public function testItDoesNotWrapAShortEnoughWord()
{
$wrapper = new Wrapper();
$this->assertEquals('word', $wrapper->wrap('word', 5));
}Wrapper.php
return $text;
Move up $wrapper to setUp
Define variables for "magic" strings and integer. (Option+Command+V)
Now for failing a long word test
public function testItWrapsAWordLongerThanLineLength()
{
$textToBeParsed = 'alongword';
$maxLineLength = 5;
$this->assertEquals("along\nword", $this->wrapper->wrap($textToBeParsed, $maxLineLength));
}Add to Wrapper.php
if (strlen($text) > $lineLength) {
return substr($text, 0, $lineLength) . "\n" . substr($text, $lineLength);
}Fix failing test
public function testITWrapsAWordSeveralTimesIfItsTooLong()
{
$textToBeParsed = 'averyverylongword';
$maxLineLength = 5;
$this->assertEquals("avery\nveryl\nongwo\nrd", $this->wrapper->wrap($textToBeParsed, $maxLineLength));
}Can you smell the while loop?
return substr($text, 0, $lineLength) . "\n" . $this->wrap(substr($text, $lineLength), $lineLength);public function testItWrapsTwoWordsWhenSpaceAtTheEndOfLine()
{
$textToBeParsed = 'word word';
$maxLineLength = 5;
$this->assertEquals("word\nword", $this->wrapper->wrap($textToBeParsed, $maxLineLength));
}
```php
return trim(substr($text, 0, $lineLength)) . "\n" . $this->wrap(substr($text, $lineLength), $lineLength);if (strlen($text) > $lineLength) {
if (strpos(substr($text, 0, $lineLength), ' ') != 0) {
return substr($text, 0, strpos($text, ' ')) . "\n" . $this->wrap(substr($text, strpos($text, ' ') + 1), $lineLength);
}
return substr($text, 0, $lineLength) . "\n" . $this->wrap(substr($text, $lineLength), $lineLength);
}
return $text;Refactor, early return
if (strlen($text) <= $lineLength) {
return $text;
}Should you write a test when you know it will pass? If you have doubts, yes. Also, tests are documentation.
public function testItWraps3WordsOn2Lines()
{
$textToBeParsed = 'word word word';
$maxLineLength = 12;
$this->assertEquals("word word\nword", $this->wrapper->wrap($textToBeParsed, $maxLineLength));
}change strpos to strrpos
It's getting harder to find failing tests. Good indication we're close to done.
public function testItWraps2WordsAtBoundry()
{
$textToBeParsed = 'word word';
$maxLineLength = 4;
$this->assertEquals("word\nword", $this->wrapper->wrap($textToBeParsed, $maxLineLength));
}Add trim()