half expected that you'd rename the two to swap names and keep the historical content/followers on this one

— rmcdowall (@NXRK) July 8, 2017

[...]

From a design perspective, having a function that potentially returns different types of result indicates a potential design flaw:

• If you're returning your result, or otherwise false if something didn't go to plan; you should probably be throwing an exception instead. If the function processing didn't go according to plan; that's an exceptional situation: leverage the fact. I know PHP itself has a habit of returning false if things didn't work, but that's just indicative of poor design - for the same reason - in PHP.
  
• If your function returns potentially different things, then it's quite possible it's doing more than one thing, which is bad design in your function. Functions should do one thing. If your function has an if/else with the true/false block handling different chunks of processing (as opposed to just handling exit situations), then this probably indicates you ought to have two functions, not one. Leave it to the calling code to decide which is the one to use.
• If your function returns two different object types which then can be used in a similar fashion in the calling code (ie: there's no if this: do that; else do this other thing in the calling code), this could indicate you ought to be returning an interface, not a concrete implementation.

There will possibly be legit situations where returning different types is actually the best thing to do. If so: all good. But that's where the benefit of using a loosely typed language comes in: just don't specify the return type of the function. But… that said… the situation probably isn't legit, so work through the preceding design considerations first to determine if you really do have one of these real edge cases where returning different types is warranted.

function f($x) {
    if ($x) {
        return true;
    }
}

function f($x) : bool {
    if ($x) {
        return true;
    }
}

f(1); // OK

f(0); // PHP Fatal error:  Uncaught TypeError: Return value of f() must be of the type boolean, none returned

function g($x) : ?bool {
    if ($x) {
        echo "returning true";
        return true;
    }

echo "returning null";
return null;
}

g(1); // returning true
g(0); // returning null

/**
 * @param bool $b
 * @return A|B
 */
function f($b){
    if ($b) {
        return new A();
    }else {
        return new B();
    }
}

• the method has not branching logic and is overwise pretty simple. Ignore it.
• we're backfilling coverage on old code we need to maintain, but it's such a mess we simply don't have time to solve all the testing shortfalls right now, so we test what is urgent (the bit we're changing), but just mark as ignore the rest of it. Now that file is green, and we can see if it stops being green.
• similar to the above but we know the code the code in question is  not long for this world. So we ignore it and stick a TODO cross referencing to the ticket that will be dealing with it. And the ticket must already be lined-up to be worked on "soon".

public function getSomeThings($rowsToGet)
{
    $thingsValues = $this->dao->getThingsFromStorage($rowsToGet);

    $things = [];
    foreach ($thingsValues as $thingValues) {
        $things[] = $this->thingFactory->createFromRawData($thingValues);
    }

    return $things;
}

return array_map(function ($thingValues) {
    return $this->thingFactory->createFromRawData($thingValues);
}, $thingsValues);

describe('comparing testing for foreach vs array_map', function() {
    given('sut', function () {
        return new ForeachVsArrayMap();
    });
    given('allObjects', function () {
        return [
            (object) ['id' => 1, 'mi' => 'tahi'],
            (object) ['id' => 2, 'mi' => 'rua'],
            (object) ['id' => 3, 'mi' => 'toru'],
        ];
    });
    describe('tests of foreach', function() {
        it('returns the numbers as objects', function () {
            $result = $this->sut->getObjects();
            expect($result)->toEqual($this->allObjects);
        });
    });
});

class ForeachVsArrayMap
{
    private $allData;

    public function __construct()
    {
        $this->allData = [
            ['id' => 1, 'mi' => 'tahi'],
            ['id' => 2, 'mi' => 'rua'],
            ['id' => 3, 'mi' => 'toru']
        ];
    }

    private function getNumbers($rows)
    {
        return array_slice($this->allData, 0, $rows);
    }

    public function getObjects($rows = 3)
    {
        $data = $this->getNumbers($rows);
        $numbers = [];
        foreach ($data as $row) {
            $numbers[] = (object) $row;
        }

        return $numbers;
    }
}

it('handles one result', function () {
    $result = $this->sut->getObjectsUsingForeach(1);
    $expected = [$this->allObjects[0]];

    expect($result)->toEqual($expected);
});

it('handles zero results', function () {
    $result = $this->sut->getObjectsUsingForeach(0);
    $expected = [];

    expect($result)->toEqual($expected);
});

public function getObjects($rows = 3)
{
    return array_map(function ($row) {
        return (object) $row;
    }, $this->getNumbers($rows));
}

public function getObjectsUsingForeach($rows = 3)
{
    $data = $this->getNumbers($rows);

    foreach ($data as $row) {
        $numbers[] = (object) $row;
    }

    // do something else with $numbers here
    // ...
}

public function getObjectsUsingForeach($rows = 3)
{
    $data = $this->getNumbers($rows);

    foreach ($data as $row) {
        $numbers = [];
        $numbers[] = (object) $row;
    }

    // do something else with $numbers here
    // ...
}

function f(int $x) : int {
    return $x;
}

try {
    $x = null;
    $y = f($x);
} catch (\TypeError $e) {
    echo $e->getMessage();
}

echo PHP_EOL . PHP_EOL;

function g(?int $x) : ?int {
    return $x;
}

$x = null;
$y = g($x);
var_dump($y);

Argument 1 passed to f() must be of the type integer, null given, called in [...][...] on line 8

NULL

 public class NullableTest {

     public static void main(String[] args){
         Integer x = null;
         Integer y = f(x);
         System.out.println(y);
     }

     private static Integer f(Integer x){
         return x;
     }
 }

• null - no methods will be mocked-out;
• an empty array - all methods will be mocked-out;
• an array of method names - just those methods will be mocked-out.

function f(?int $x = 0){
    if (is_null($x)){
        $x = 0;
    }
    // rest of function, which requires $x to be an int
}

function f(?int $x) : int {
    return $x;
}

try {
    $y = f();
} catch (\TypeError $e) {
    echo $e->getMessage();
}

$peopleData = $conn
    ->query('SELECT date, name FROM mapexampledata')
    ->fetchAll(PDO::FETCH_ASSOC | PDO::FETCH_COLUMN | PDO::FETCH_UNIQUE);

var_dump($peopleData);

[
"2008-11-08" => "Jacinda",
    "1990-10-27" => "Bill",
    "2014-09-20" => "James",
    "1979-05-24" => "Winston"
]

class PersonalMilestone {
    public $date;
    public $name;

    function __construct($date, $name) {
        $this->date = $date;
        $this->name = $name;
    }
}

$peopleData = ["2008-11-08" => "Jacinda", "1990-10-27" => "Bill", "2014-09-20" => "James", "1979-05-24" => "Winston"];

$people = array_map(function ($name) {
    return new PersonalMilestone(
$date, // dammit this won't work: array_map only gives me the value, not the key
        $name
    );
}, $peopleData);

$peopleData = ["2008-11-08" => "Jacinda", "1990-10-27" => "Bill", "2014-09-20" => "James", "1979-05-24" => "Winston"];

$keys = array_keys($peopleData);

$people = array_map(function ($name, $date) {
    return new PersonalMilestone($date, $name);
}, $peopleData, $keys);

var_dump($people);

array(4) {
  [0]=>
  object(PersonalMilestone)#2 (2) {
    ["date"]=>
    string(10) "2008-11-08"
    ["name"]=>
    string(7) "Jacinda"
  }
  [1]=>
  object(PersonalMilestone)#3 (2) {
    ["date"]=>
    string(10) "1990-10-27"
    ["name"]=>
    string(4) "Bill"
  }
  [2]=>
  object(PersonalMilestone)#4 (2) {
    ["date"]=>
    string(10) "2014-09-20"
    ["name"]=>
    string(5) "James"
  }
  [3]=>
  object(PersonalMilestone)#5 (2) {
    ["date"]=>
    string(10) "1979-05-24"
    ["name"]=>
    string(7) "Winston"
  }
}

$peopleData = ["2008-11-08" => "Jacinda", "1990-10-27" => "Bill", "2014-09-20" => "James", "1979-05-24" => "Winston"];
var_dump($peopleData);

$keys = array_keys($peopleData);
$keysIndexedByKeys = array_combine($keys, $keys);
var_dump($keysIndexedByKeys);

$people = array_map(function ($name, $date) {
    return new PersonalMilestone($date, $name);
}, $peopleData, $keys);

var_dump($people);

array(4) {
  ["2008-11-08"]=>
  string(7) "Jacinda"
  ["1990-10-27"]=>
  string(4) "Bill"
  ["2014-09-20"]=>
  string(5) "James"
  ["1979-05-24"]=>
  string(7) "Winston"
}
array(4) {
  ["2008-11-08"]=>
  string(10) "2008-11-08"
  ["1990-10-27"]=>
  string(10) "1990-10-27"
  ["2014-09-20"]=>
  string(10) "2014-09-20"
  ["1979-05-24"]=>
  string(10) "1979-05-24"
}
array(4) {
  [0]=>
  object(PersonalMilestone)#2 (2) {
    ["date"]=>
    string(10) "2008-11-08"
    ["name"]=>
    string(7) "Jacinda"
  }
  [1]=>
  object(PersonalMilestone)#3 (2) {
    ["date"]=>
    string(10) "1990-10-27"
    ["name"]=>
    string(4) "Bill"
  }
  [2]=>
  object(PersonalMilestone)#4 (2) {
    ["date"]=>
    string(10) "2014-09-20"
    ["name"]=>
    string(5) "James"
  }
  [3]=>
  object(PersonalMilestone)#5 (2) {
    ["date"]=>
    string(10) "1979-05-24"
    ["name"]=>
    string(7) "Winston"
  }
}

$people = [];
foreach ($peopleData as $date => $name) {
    $people[$date] = new PersonalMilestone($date, $name);
}

var_dump($people);

array(4) {
  ["2008-11-08"]=>
  object(PersonalMilestone)#1 (2) {
    ["date"]=>
    string(10) "2008-11-08"
    ["name"]=>
    string(7) "Jacinda"
  }
  ["1990-10-27"]=>
  object(PersonalMilestone)#2 (2) {
    ["date"]=>
    string(10) "1990-10-27"
    ["name"]=>
    string(4) "Bill"
  }
  ["2014-09-20"]=>
  object(PersonalMilestone)#3 (2) {
    ["date"]=>
    string(10) "2014-09-20"
    ["name"]=>
    string(5) "James"
  }
  ["1979-05-24"]=>
  object(PersonalMilestone)#4 (2) {
    ["date"]=>
    string(10) "1979-05-24"
    ["name"]=>
    string(7) "Winston"
  }
}

$keys = new ArrayIterator(array_keys($peopleData));

$people = array_map(function ($name) use ($keys) {
$date = $keys->current();
$keys->next();
    return new PersonalMilestone($date, $name);
}, $peopleData);

[
    "2008-11-08" => "Jacinda",
    "1990-10-27" => "Bill",
    "2014-09-20" => "James",
    "1979-05-24" => "Winston"
]

array(4) {
  '2008-11-08' =>
  class IndexedPerson#3 (2) {
    public $date =>
    string(10) "2008-11-08"
    public $name =>
    string(7) "Jacinda"
  }
  '1990-10-27' =>
  class IndexedPerson#4 (2) {
    public $date =>
    string(10) "1990-10-27"
    public $name =>
    string(4) "Bill"
  }
  '2014-09-20' =>
  class IndexedPerson#5 (2) {
    public $date =>
    string(10) "2014-09-20"
    public $name =>
    string(5) "James"
  }
  '1979-05-24' =>
  class IndexedPerson#6 (2) {
    public $date =>
    string(10) "1979-05-24"
    public $name =>
    string(7) "Winston"
  }
}

CFML

peopleData = {"2008-11-08" = "Jacinda", "1990-10-27" = "Bill", "2014-09-20" = "James", "1979-05-24" = "Winston"}

people = peopleData.map((date, name) => new IndexedPerson(date, name))

people.each((date, person) => echo("#date# => #person#<br>"))

component {

    function init(date, name) {
        this.date = date
        this.name = name
    }

    string function _toString() {
        return "{date:#this.date#; name: #this.name#}"
    }
}

people = peopleData.map((date, name) => new IndexedPerson(date, name))

1979-05-24 => {date:1979-05-24; name: Winston}
2014-09-20 => {date:2014-09-20; name: James}
1990-10-27 => {date:1990-10-27; name: Bill}
2008-11-08 => {date:2008-11-08; name: Jacinda}

JS

class IndexedPerson {
    constructor(date, name) {
        this.date = date
        this.name = name
    }
}

let peopleData = {"2008-11-08": "Jacinda", "1990-10-27": "Bill", "2014-09-20": "James", "1979-05-24": "Winston"}

let people = Object.entries(peopleData).reduce(function (people, personData) {
    people.set(personData[0], new IndexedPerson(personData[0], personData[1]))
    return people
}, new Map())

console.log(people)

Map {
  '2008-11-08' => IndexedPerson { date: '2008-11-08', name: 'Jacinda' },
  '1990-10-27' => IndexedPerson { date: '1990-10-27', name: 'Bill' },
  '2014-09-20' => IndexedPerson { date: '2014-09-20', name: 'James' },
  '1979-05-24' => IndexedPerson { date: '1979-05-24', name: 'Winston' } }

Java

import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;

class IndexedPerson {
String date;
String name;

    public IndexedPerson(String date, String name) {
        this.date = date;
        this.name = name;
    }

    public String toString(){
        return String.format("{date: %s, name: %s}", this.date, this.name);
    }
}

class Collect {

    public static void main(String[] args) {

HashMap<String,String> peopleData = loadData();

HashMap<String, IndexedPerson> people = mapToPeople(peopleData);

        dumpIdents(people);
    }

    private static HashMap<String,String> loadData(){
HashMap<String,String> peopleData = new HashMap<String,String>();

        peopleData.put("2008-11-08", "Jacinda");
        peopleData.put("1990-10-27", "Bill");
        peopleData.put("2014-09-20", "James");
        peopleData.put("1979-05-24", "Winston");

        return peopleData;
    }

    private static HashMap<String,IndexedPerson> mapToPeople(HashMap<String,String> peopleData) {
HashMap<String, IndexedPerson> people = (HashMap<String, IndexedPerson>) peopleData.entrySet().stream()
.collect(Collectors.toMap(
                e -> e.getKey(),
                e -> new IndexedPerson(e.getKey(), e.getValue())
            ));

        return people;
    }

    private static void dumpIdents(HashMap<String,IndexedPerson> people) {
        for (Map.Entry<String, IndexedPerson> entry : people.entrySet()) {
            System.out.println(String.format("%s => %s", entry.getKey(), entry.getValue()));
        }
    }

}

1979-05-24 => {date: 1979-05-24, name: Winston}
2014-09-20 => {date: 2014-09-20, name: James}
1990-10-27 => {date: 1990-10-27, name: Bill}
2008-11-08 => {date: 2008-11-08, name: Jacinda}

Groovy

class IndexedPerson {
    String date
    String name

    IndexedPerson(String date, String name) {
        this.date = date;
        this.name = name;
    }

    String toString(){
        String.format("date: %s, name: %s", this.date, this.name)
    }
}

peopleData = ["2008-11-08": "Jacinda", "1990-10-27": "Bill", "2014-09-20": "James", "1979-05-24": "Winston"]

people = peopleData.collectEntries {date, name -> [date, new IndexedPerson(date, name)]}

people.each {date, person -> println String.format("%s => {%s}", date, person)}

2008-11-08 => {date: 2008-11-08, name: Jacinda}
1990-10-27 => {date: 1990-10-27, name: Bill}
2014-09-20 => {date: 2014-09-20, name: James}
1979-05-24 => {date: 1979-05-24, name: Winston}

Ruby

class IndexedPerson

    def initialize(date, name)
        @date = date
        @name = name
    end

    def inspect
        "{date:#{@date}; name: #{@name}}\n"
    end
end

peopleData = {"2008-11-08" => "Jacinda", "1990-10-27" => "Bill", "2014-09-20" => "James", "1979-05-24" => "Winston"}

people = peopleData.merge(peopleData) do |date, name|
    IndexedPerson.new(date, name)
end

puts people

{"2008-11-08"=>{date:2008-11-08; name: Jacinda}
, "1990-10-27"=>{date:1990-10-27; name: Bill}
, "2014-09-20"=>{date:2014-09-20; name: James}
, "1979-05-24"=>{date:1979-05-24; name: Winston}
}

Python

class IndexedPerson:
    def __init__(self, date, name):
        self.date = date
        self.name = name

    def __repr__(self):
        return "{{date: {date}, name: {name}}}".format(date=self.date, name=self.name)

people_data = {"2008-11-08": "Jacinda", "1990-10-27": "Bill", "2014-09-20": "James", "1979-05-24": "Winston"}

people = {date: IndexedPerson(date, name) for (date, name) in people_data.items()}

print("\n".join(['%s => %s' % (date, person) for (date, person) in people.items()]))

Clojure

(defrecord IndexedPerson [date name])

(def people-data (array-map "2008-11-08" "Jacinda" "1990-10-27" "Bill" "2014-09-20" "James" "1979-05-24" "Winston"))

(def people
  (reduce-kv
    (fn [people date name] (conj people (array-map date (IndexedPerson. date name))))
    (array-map)
    people-data))

(print people)

{2008-11-08 #user.IndexedPerson{:date 2008-11-08, :name Jacinda},
1990-10-27 #user.IndexedPerson{:date 1990-10-27, :name Bill},
2014-09-20 #user.IndexedPerson{:date 2014-09-20, :name James},
1979-05-24 #user.IndexedPerson{:date 1979-05-24, :name Winston}}

Summary

In order of ease of use and how pleasing the solution seemed:
1 Python
2 Ruby
3 Groovy
4 CFML
5 JS
6 PHP
7 Java

— Adam Cameron (@adam_cameron) November 25, 2017

1. Python
2. Ruby
3. Groovy
4. CFML
5. Clojure
6. JS
7. PHP
8. Java

Cool. If you'd like a Golang example just let me know. Be fun to collaborate.

— Barry O Sullivan (@barryosull) November 26, 2017

function takesArray(array $a){
    return $a;
}

var_dump(takesArray(["tahi", "rua", "toru", "wha"]));

array(4) {
  [0]=>
  string(4) "tahi"
  [1]=>
  string(3) "rua"
  [2]=>
  string(4) "toru"
  [3]=>
  string(3) "wha"
}

<?php
function takesArray(array $a){
    return $a;
}

try {
    $a = takesArray("NOT_AN_ARRAY");
} catch (\Throwable $t) {
    echo $t;
}

TypeError:
Argument 1 passed to takesArray() must be of the type array, string given,
called in [...][...] on line 7 and defined in [...][...]:2
Stack trace:
#0 [...][...](7): takesArray('NOT_AN_ARRAY')
#1 {main}

function getFirstName(array $name){
    return $name['firstName'];
}

$firstName = getFirstName(["lastName" => "Cameron", "firstName" => "Adam"]);

echo $firstName;

class Name {
    public $lastName;
    public $firstName;

    function __construct($lastName, $firstName) {
        $this->lastName = $lastName;
        $this->firstName = $firstName;
    }
}

function getFirstName(Name $name){
    return $name->firstName;
}

function filterOutEarlierDates(array $dates, int $year){
    $cutOff = new \DateTime("$year-01-01");

    $filtered = array_filter($dates, function (\DateTimeInterface $date) use ($cutOff) {
        $diff = $date->diff($cutOff);
        return $diff->invert === 1;
    });

    return array_values($filtered);
}

$dobs = [
    new \DateTime("1968-12-20"),
    new \DateTime("1970-02-17"),
    new \DateTime("2011-03-24"),
    new \DateTime("2016-08-17")
];
$cutOff = 2011;

$youngins = filterOutEarlierDates($dobs, $cutOff);

var_dump($youngins);

function array_some(array $array, callable $callback) {
    foreach ($array as $key => $value) {
        $result = $callback($value, $key);
        if ($result) {
            return true;
        }
    }
    return false;
}

$colours = ["whero", "karaka", "kowhai", "kakariki", "kikorangi", "poropango", "papura"];

$containsSixLetterWords = array_some($colours, function ($colour) {
   return strlen($colour) === 6; 
});

var_dump($containsSixLetterWords);

$numbers = [
    "one" => "tahi",
    "two" => "rua",
    "three" => "toru",
    "four" => "wha",
    "five" => "rima",
    "six" => "ono",
    "seven" => "whitu",
    "eight" => "ware",
    "nine" => "iwa",
    "ten" => "tekau"
];

$hasShortKeys = array_some($numbers, function ($number, $key) {
   return strlen($key) <= 3; 
});

var_dump($hasShortKeys);

Actually there's a similar issue with my type checking of the $callback parameter there. It can't be any callable: it needs to be a callable that takes a coupla arguments and returns a boolean. In C# I guess we'd use a Delegate for that, but there's no such construct in PHP. So I should probably settle for giving the argument a clear name ($callback probably isn't good enough here), and dispense with the type check.

class ColourCollection implements \Iterator {
    private $position = 0;
    private $colours;  

    public function __construct($colours) {
        $this->position = 0;
        $this->colours = $colours;
    }

    public function rewind() {
        $this->position = 0;
    }

    public function current() {
        return $this->colours[$this->position];
    }

    public function key() {
        return $this->position;
    }

    public function next() {
        ++$this->position;
    }

    public function valid() {
        return isset($this->colours[$this->position]);
    }
}

$rainbow = new ColourCollection($colours);

Fatal error:
Uncaught TypeError: Argument 1 passed to array_some() must be of the type array, object given,
 called in [...][...] on line 48 and defined in [...][...]:2
Stack trace:
#0 [...][...](48): array_some(Object(ColourCollection), Object(Closure))
#1 {main}
  thrown in [...][...] on line 2

class SpecialInterestingReportEmail {

    public $from;
    public $to;
    public $subject;
    public $body;

    public static $bodyTemplate = "specialInterestingReportEmail.html.twig";

    function __construct($from, $to, $subject, $body) {
        $this->from = $from;
        $this->to = $to;
        $this->subject = $subject;
        $this->body = $body;
    }
}

function createSpecialInterestingReportEmail($special, $interesting) {
    $body = $this-twigService->render(
        SpecialInterestingReportEmail::bodyTemplate,
        [
            "special" => $special,
            "interesting" => $interesting
        ]
    )
    return new SpecialInterestingReportEmail(
        $this->addressesForReport->from,
        $this->addressesForReport->to,
        $this->reportSubject,
        $body
    );
}

Notice:
All interaction I mention below with my colleagues is paraphrased, embellished, or outright changed to make my point. I am not quoting anyone, and take this as a work of fiction. It's also drawn from previous similar conversations I've had on this topic.

$email = [
    "from" => "from@example.com",
    "to" => "to@example.com",
    "subject" => "Example subject",
    "body" => "Example body"
];

$fromAddress = $email["from"];

$email = new Email(
    "from@example.com",
    "to@example.com",
    "Example subject",
    "Example body"
);

$fromAddress = $email->from;

{
    "errors": [
        "Internal Server Error"
    ]
}

{"errors": ["Expected argument of type \"array or Traversable and ArrayAccess\", \"string\" given"]}

{
  "firstName" : "Zachary",
  "lastName" : "Cameron Lynch",
  "address" : ""
}

{
    "firstName" : "Zachary",
    "lastName" : "Cameron Lynch",
    "address" : {
        "street" : "123 Some Street",
        "city" : "Our City"
    }
}

use PHPUnit\Framework\TestCase;
use Symfony\Component\Validator\Constraints\Length;
use Symfony\Component\Validator\Constraints\NotBlank;
use Symfony\Component\Validator\Validation;

class StringValidatorTest extends TestCase
{
    public function testExampleFromDocumentation()
    {
        $validator = Validation::createValidator();
        $violations = $validator->validate(
            'Bernhard',
            [
                new Length(['min' => 10]),
                new NotBlank(),
            ]
        );

        $this->assertCount(1, $violations);
        $this->assertEquals(
            'This value is too short. It should have 10 characters or more.',
            $violations[0]->getMessage()
        );
    }
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 218 ms, Memory: 4.00MB

OK (1 test, 2 assertions)

namespace me\adamcameron\general\validation\collectionIssue;

use Symfony\Component\Validator\Constraints\Type;
use Symfony\Component\Validator\Validation;

class IntegerValidator
{

    private $validator;
    private $constraints;

    public function __construct()
    {
        $this->validator = Validation::createValidator();
        $this->setConstraints();
    }

    private function setConstraints()
    {
$this->constraints = [
new Type(['type' => 'integer'])
];
    }

    public function validate($value)
    {
        return $this->validator->validate($value, $this->constraints);
    }
}

<?php

namespace me\adamcameron\general\test\validation\collectionIssue;

use me\adamcameron\general\validation\collectionIssue\IntegerValidator;
use PHPUnit\Framework\TestCase;

class IntegerValidatorTest extends TestCase
{
    use ViolationAssertions;

    private $validator;

    protected function setUp()
    {
        $this->validator = new IntegerValidator();
    }

    /** @dataProvider provideCasesForValidateTests */
    public function testValidate($validValue)
    {
        $violations = $this->validator->validate($validValue);
        $this->assertHasNoViolations($violations);
    }

    public function provideCasesForValidateTests()
    {
        return [
            'has value' => ['value' => 42],
            'is null' => ['value' => null]
        ];
    }

    /** @dataProvider provideCasesForViolationsTests */
    public function testValidateReturnsViolationsWhenConstraintsBroken($invalidValue)
    {
        $violations = $this->validator->validate($invalidValue);
        $this->assertHasViolations($violations);
    }

    public function provideCasesForViolationsTests()
    {
        return [
            'string' => ['value' => 'forty-two'],
            'integer string' => ['value' => '42'],
            'float' => ['value' => 4.2],
            'integer as float' => ['value' => 42.0],
            'array' => ['value' => [42]]
        ];
    }
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.......                                                             7 / 7 (100%)

Time: 204 ms, Memory: 4.00MB

OK (7 tests, 14 assertions)

namespace me\adamcameron\general\test\validation\collectionIssue;

use Symfony\Component\Validator\ConstraintViolationList;

trait ViolationAssertions
{
    public function assertHasNoViolations($violations)
    {
        $this->assertInstanceOf(ConstraintViolationList::class, $violations);
        $this->assertEmpty($violations);
    }

    public function assertHasViolations($violations)
    {
        $this->assertInstanceOf(ConstraintViolationList::class, $violations);
        $this->assertNotEmpty($violations);
    }
}

namespace me\adamcameron\general\validation\collectionIssue;

use Symfony\Component\Validator\Constraints\Collection;
use Symfony\Component\Validator\Constraints\Type;
use Symfony\Component\Validator\Validation;

class CollectionValidator
{

    private $validator;
    private $constraints;

    public function __construct()
    {
        $this->validator = Validation::createValidator();
        $this->setConstraints();
    }

    private function setConstraints()
    {
        $this->constraints = [
            new Collection([
                'fields' => [
                    'field1' => [new Type(['type'=>'integer'])]
                ],
                'allowMissingFields' => true,
                'allowExtraFields' => true
            ])
        ];
    }

    public function validate($value = null)
    {
        return $this->validator->validate($value, $this->constraints);
    }
}

namespace me\adamcameron\general\test\validation\collectionIssue;

use me\adamcameron\general\validation\collectionIssue\CollectionValidator;
use PHPUnit\Framework\TestCase;

class CollectionValidatorTest extends TestCase
{
    use ViolationAssertions;

    private $validator;

    protected function setUp()
    {
        $this->validator = new CollectionValidator();
    }

    /** @dataProvider provideCasesForValidateEmptyCollectionTests */
    public function testValidateWithValidButEmptyCollectionTypeIsOk($validValue)
    {
        $violations = $this->validator->validate($validValue);
        $this->assertHasNoViolations($violations);
    }

    public function provideCasesForValidateEmptyCollectionTests()
    {
        return [
            'array' => ['value' => []],
            'iterator' => ['value' => new \ArrayIterator()]
        ];
    }
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

..                                                                  2 / 2 (100%)

Time: 187 ms, Memory: 4.00MB

OK (2 tests, 4 assertions)

public function testValidateWithIntegerField1ValueShouldPass()
{
    $violations = $this->validator->validate(['field1'=>42]);
    $this->assertHasNoViolations($violations);
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 211 ms, Memory: 4.00MB

OK (1 test, 2 assertions)

public function testValidateWithNonIntegerField1ValueShouldHaveViolation()
{
    $violations = $this->validator->validate(['field1'=>'NOT_AN_INTEGER']);
    $this->assertHasViolations($violations);
    $this->assertSame('This value should be of type integer.', $violations[0]->getMessage());
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 191 ms, Memory: 4.00MB

OK (1 test, 3 assertions)

public function testValidateWithOnlyOtherFieldsShouldPass()
{
    $violations = $this->validator->validate(['anotherField'=>'another value']);
    $this->assertHasNoViolations($violations);
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 191 ms, Memory: 4.00MB

OK (1 test, 2 assertions)

public function testValidateWithNullIsApparentlyOK()
{
    $violations = $this->validator->validate(null);
    $this->assertHasNoViolations($violations);
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 259 ms, Memory: 4.00MB

OK (1 test, 2 assertions)

public function testValidateWithNonTraversableShouldCauseViolation()
{
    $violations = $this->validator->validate('a string');
    $this->assertHasViolations($violations);
}

PHPUnit 7.2.6 by Sebastian Bergmann and contributors.

E                                                                   1 / 1 (100%)

Time: 194 ms, Memory: 4.00MB

There was 1 error:

1) me\adamcameron\general\test\validation\collectionIssue\CollectionValidatorTest::testValidateWithNonTraversableShouldCauseViolation
Symfony\Component\Validator\Exception\UnexpectedTypeException: Expected argument of type "array or Traversable and ArrayAccess", "string" given

C:\src\php\general\vendor\symfony\validator\Constraints\CollectionValidator.php:37
C:\src\php\general\vendor\symfony\validator\Validator\RecursiveContextualValidator.php:829
C:\src\php\general\vendor\symfony\validator\Validator\RecursiveContextualValidator.php:675
C:\src\php\general\vendor\symfony\validator\Validator\RecursiveContextualValidator.php:118
C:\src\php\general\vendor\symfony\validator\Validator\RecursiveValidator.php:100
C:\src\php\general\src\validation\collectionIssue\CollectionValidator.php:36
C:\src\php\general\test\validation\collectionIssue\CollectionValidatorTest.php:63

ERRORS!
Tests: 1, Assertions: 0, Errors: 1.

public function validate($value, Constraint $constraint)
{
if (!$constraint instanceof Collection) {
throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\Collection');
}
    if (null === $value) {
        return;
    }
    if (!is_array($value) && !($value instanceof \Traversable && $value instanceof \ArrayAccess)) {
        throw new UnexpectedTypeException($value, 'array or Traversable and ArrayAccess');
    }

class ThingRepository {

    public function getThing($id) {
$dao = DaoFactory::getThingDao();
        $dbData = $dao->getThing($id);

        return Thing::createFromArray($dbData);
    }
}

class ThingRepositoryTest extends TestCase {

    private $repository;

    protected function setUp() : void {
        $this->repository = new ThingRepository();
    }

    public function testGetThingReturnsCorrectThingForId(){
        $testId = 17;
        $expectedName = "Thing 1";
        $thing = $this->repository->getThing(17);

        $this->assertInstanceOf(Thing::class, $thing);
        $this->assertSame($testId, $thing->id);
        $this->assertSame($expectedName, $thing->name);
    }
}

class ThingRepositoryExistingTestUpdatedTest extends TestCase {

    private $repository;
    private $dao;

    protected function setUp() : void {
        $this->dao = $this->createMock(ThingDao::class);
        $this->repository = new ThingRepositoryWithDaoDependency($this->dao);
    }

    public function testGetThingReturnsCorrectThingForId(){
// implementation that now uses mocked DAO
    }
}

Fixing other tests so they won't fail after we make the change is not TDD, it's just technical debt recovery. If we're doing TDD, then we need to start with an explicit test case for the change we're going to make.

class ThingRepositoryTest extends TestCase {

    private $repository;
    private $dao;

    protected function setUp() : void {
$this->dao = $this->createMock(ThingDao::class);
$this->repository = new ThingRepositoryWithDaoDependency($this->dao);
    }

public function testGetThingUsesDaoPassedIntoConstructor(){
        $testId = 17;
        $mockedThingData = ['id'=>$testId, 'thing' => 'stuff'];

$this->dao
->expects($this->once())
->method('getThing')
->with($testId)
->willReturn($mockedThingData);

        $result = $this->repository->getThing($testId);

        $this->assertEquals(
            new Thing($mockedThingData['id'], $mockedThingData['thing']),
            $result
        )
    }

    // ... rest of test cases that were already there, including this one...

    public function testGetThingReturnsCorrectThingForID(){
        // updated implementation that doesn't break because of the DAO change
    }
}

class ThingRepository {

    private $dao;

    public function __construct($dao) {
        $this->dao = $dao;
    }

    public function getThing($id){
        $dbData = $this->dao->getThing($id);

        return Thing::createFromArray($dbData);
    }
}

As a rule of thumb... if you don't start your TDD work by typing in a case name - eg testGetThingUsesDaoPassedIntoConstructor - then you're not doing TDD, you are just doing maintenance code. These are... not the same thing.

public function testGetThingReturnsCorrectThingForId(){
    $testId = 17;
    $expectedName = "Thing 1";

    $this->dao->expects($this->once())
        ->method('getThing')
        ->with($testId)
        ->willReturn(['id' => $testId, 'name' => $expectedName]);

    $thing = $this->repository->getThing(17);

    $this->assertInstanceOf(Thing::class, $thing);
    $this->assertSame($testId, $thing->id);
    $this->assertSame($expectedName, $thing->name);
}

Fixing other tests so they won't fail after we make the change is not TDD, it's just technical debt recovery. If we're doing TDD, then we need to start with an explicit test case for the change we're going to make.

public function testGetThingUsesDaoPassedIntoConstructor()
{
    $this->testGetThingReturnsCorrectThingForId();
}

class MyService
{
    private $dependency;

    function __construct(MyDependency $dependency){
        $this->dependency = $dependency;
    }

    function myMethod() {
        return $this->dependency->someMethod();
    }
}

class MyDependency
{
    function someMethod(){
        return "ORIGINAL VALUE";
    }
}

class MyServiceTest extends TestCase
{

    /** @dataProvider provideTestCasesForMyMethodTests */
    public function testMyMethodViaDataProvider($dependency)
    {
        $dependency
            ->expects($this->once())
            ->method('someMethod')
            ->willReturn("MOCKED VALUE");

        $service = new MyService($dependency);

        $result = $service->myMethod();

        $this->assertEquals("MOCKED VALUE", $result);
    }

    public function provideTestCasesForMyMethodTests(){
        return [
            'it should call someMethod once' => [
                'dependency' => $this->createMock(MyDependency::class)
            ]
        ];
    }
}

$dependency
    ->expects($this->exactly(10))
    ->method('someMethod')
    ->willReturn("MOCKED VALUE");

public function testMyMethodViaInlineMock()
{
    $dependency = $this->createMock(MyDependency::class);
    $dependency
        ->expects($this->once())
        ->method('someMethod')
        ->willReturn("MOCKED VALUE");

    $service = new MyService($dependency);

    $result = $service->myMethod();

    $this->assertEquals("MOCKED VALUE", $result);
}

function myOtherMethod(){
$this->dependency->someOtherMethod();
$this->dependency->someOtherMethod();
$this->dependency->someOtherMethod();
$this->dependency->someOtherMethod();
    return  $this->dependency->someOtherMethod();
}

/** @dataProvider provideTestCasesForMyOtherMethodTests */
public function testMyOtherMethodCallsDependencyMethodEnoughTimes($dependency, $expectedCount) {
    $dependency
        ->expects($this->exactly($expectedCount))
        ->method('someOtherMethod')
        ->willReturn("MOCKED VALUE");

    $service = new MyService($dependency);

    $result = $service->myOtherMethod();

    $this->assertEquals("MOCKED VALUE", $result);
}

public function provideTestCasesForMyOtherMethodTests(){
    return [
        'it expects myOtherMethod to be called 3 times' => [
            'dependency' => $this->createMock(MyDependency::class),
            'expectedCount' => 3
        ],
        'it expects myOtherMethod to be called 4 times' => [
            'dependency' => $this->createMock(MyDependency::class),
            'expectedCount' => 4
        ],
        'it expects myOtherMethod to be called 5 times' => [
            'dependency' => $this->createMock(MyDependency::class),
            'expectedCount' => 5
        ],
        'it expects myOtherMethod to be called 6 times' => [
            'dependency' => $this->createMock(MyDependency::class),
            'expectedCount' => 6
        ],
        'it expects myOtherMethod to be called 7 times' => [
            'dependency' => $this->createMock(MyDependency::class),
            'expectedCount' => 7
        ]
    ];
}

/** @dataProvider provideTestCasesForMyOtherMethodTests */
public function testMyOtherMethodCallsDependencyMethodEnoughTimesWithDependencyCreatedInTest($_, $expectedCount) {
$dependency = $this->createMock(MyDependency::class);
    $dependency
        ->expects($this->exactly($expectedCount))
        ->method('someOtherMethod')
        ->willReturn("MOCKED VALUE");

    $service = new MyService($dependency);

    $result = $service->myOtherMethod();

    $this->assertEquals("MOCKED VALUE", $result);
}

public function verify(): void
{
    printf(PHP_EOL . "InvocationHandler::verify called with %d matchers" . PHP_EOL, count($this->matchers));

    foreach ($this->matchers as $matcher) {
        $matcher->verify();
    }

private function verifyMockObjects(): void
{
    foreach ($this->mockObjects as $mockObject) {
        if ($mockObject->__phpunit_hasMatchers()) {
            $this->numAssertions++;
        }

$mockObject->__phpunit_verify(
$this->shouldInvocationMockerBeReset($mockObject)
);
    }

public function getMock(): MockObject
{
    $object = $this->generator->getMock(
        $this->type,
        !$this->emptyMethodsArray ? $this->methods : null,
        $this->constructorArgs,
        $this->mockClassName,
        $this->originalConstructor,
        $this->originalClone,
        $this->autoload,
        $this->cloneArguments,
        $this->callOriginalMethods,
        $this->proxyTarget,
        $this->allowMockingUnknownTypes,
        $this->returnValueGeneration
    );

    $this->testCase->registerMockObject($object);

    return $object;
}

// ...

public function registerMockObject(MockObject $mockObject): void
{
    $this->mockObjects[] = $mockObject;
}

function myMethod() {
    return $this->dependency->someMethod();
}

G'day:

This is solely a heads-up regarding some potential reading for you.

A bloke called Ben Brumm came across one of my old articles, "CFML: an exercise in converting a nested set tree into an adjacency list tree". He's hit me up and asked me to add a link to that to an article he's written "Hierarchical Data in SQL: The Ultimate Guide". I've done that, but that article is buried in the mists of time back in 2015. I figured he could benefit from a more contemporary nudge too. So here it is. Me nudging.

In other news people have been urging me to get back to this blog, but I'm afraid I still am not finding anything new to write about. So... erm... yeah. If something leaps out at me I do fully intend to come back to this, but... not for now.

Righto.

-- 

Adam

 G'day:

Bloody Coldfusion. OK so why am I writing about a ColdFusion issue? Well about 80% of it is "not having a great deal else to do today", about 10% of being interested in this issue Mingo found. And 10% it being an excuse to mess around with Docker a bit. I am currently - and slowly - teaching myself about Docker, so there's some practise for me getting a ColdFusion instance up and running on this PC (which I no-longer have any type of CFML engine installed on).

OK so what's the issue. Mingoposted this on Twitter:

foo = { bar = 1 };
cachePut( 'foobar', foo );

foo.bar = 2;

writeDump( cacheGet( 'foobar' ) );

Obviously (?) what one would expect here is 1. What gets put into cache would be a copy of the struct right?

Well... um... here goes...

... errr... what?

It looks like ColdFusion is like only putting a reference to the struct into cache. So any code changing the data in the struct is changing it in CFML as well as changing it in cache. This does not seem right.

I did a quick google and found a ticket in Adobe's system about this: CF-3989480 - cacheGet returns values by reference. The important bit to note is that it's closed with

Update: It looks like this is actually expected behavior in Ehcache. Unfortunately, it's not documented in the ColdFusion documentation anywhere, but Ehcache actually has two configurable parameters (as of v. 2.10) called copyOnRead and copyOnWrite that determine whether values returned from the cache are by reference or copies of the original values. By default, items are returned by reference. Unfortunately we can't take advantage of these parameters right now as CF 9.0.1 implements Ehcache 2.0.

I decided to have a look what we could do about this on ColdFusion 2018, hoping that its embedded implementation of Ehcache has been updated since Rob wrote that in 2010.

Firstly I checked the Ehcache docs for these two settings: copyOnWrite and copyOnRead. This is straight forward (from "copyOnRead and copyOnWrite cache configuration"):

<cache name="copyCache"
    maxEntriesLocalHeap="10"
    eternal="false"
    timeToIdleSeconds="5"
    timeToLiveSeconds="10"
copyOnRead="true"
copyOnWrite="true">
<persistence strategy="none"/>
<copyStrategy class="com.company.ehcache.MyCopyStrategy"/>
</cache>

The docs also confirm these are off by default

Next where's the file?

Cool. BTW I just guessed at that file name.

So in there we have this (way down at line 471):

<!--
Mandatory Default Cache configuration. These settings will be applied to caches
created programmtically using CacheManager.add(String cacheName).

The defaultCache has an implicit name "default" which is a reserved cache name.
-->
<defaultCache
    maxElementsInMemory="10000"
    eternal="false"
    timeToIdleSeconds="86400"
    timeToLiveSeconds="86400"
    overflowToDisk="false"
    diskSpoolBufferSizeMB="30"
    maxElementsOnDisk="10000000"
    diskPersistent="false"
    diskExpiryThreadIntervalSeconds="3600"
    memoryStoreEvictionPolicy="LRU"
    clearOnFlush="true"
    statistics="true"
/>

That looked promising, so I updated it to use copyOnWrite:

<defaultCache
    maxElementsInMemory="10000"
    eternal="false"
    timeToIdleSeconds="86400"
    timeToLiveSeconds="86400"
    overflowToDisk="false"
    diskSpoolBufferSizeMB="30"
    maxElementsOnDisk="10000000"
    diskPersistent="false"
    diskExpiryThreadIntervalSeconds="3600"
    memoryStoreEvictionPolicy="LRU"
    clearOnFlush="true"
    statistics="true"
copyOnWrite="false"
/>

Whatever I put into cache, I want it to be decoupled from the code immediately, hence doing the copy-on-write.

I restarted CF and ran the code again:

Yay! We are getting the "expected" result now: 1

Don't really have much else to say about this. I'm mulling over writing down what I did to get ColdFusion 2018 up and running via Docker instead of installing it. Let's see if I can be arsed...

Righto.

-- 

Adam

G'day:
Firstly, don't take this as some sort of informed tutorial as to how things should be done. I am completely new to Docker, and don't yet know my arse from my elbow with it. Today I decided to look at an issue my mate was having with ColdFusion (see "ColdFusion: looking at an issue Mingo had with ehcache and cachePut and cacheGet"). These days I do not have CF installed anywhere, so to look into this issue, I needed to run it somehow. I was not gonna do an actual full install just for this. Also I've been trying - slowly -  to get up to speed with Docker, and this seemed to be a sitter for doing something newish with it. Also note that this is not the sort of issue I could just use trycf.com to run some code, as it required looking at some server config.

All I'm gonna do here is document what I had to do today to solve the problem in that other article.

I am running on Windows 10 Pro, I have WSL installed, and I'm running an Ubuntu distribution, and using bash within that. I could use powershell, but I so seldom use it, I'm actually slightly more comfortable with bash. For general Windows command-line stuff I usually just use the default shell, and it didn't even occur to me until just now to check if the docker CLI actually works in that shell, given all the docs I have read use either Powershell or some *nix shell. I just checked and seems it does work in the default shell too. Ha. Ah well, I'm gonna stick with bash for this.

I've also already got Docker Desktop & CLI installed and are running. I've worked through the Getting Started material on the Docker website, and that's really about it, other than a coupla additional experiments.

Right. I'd been made aware that Adobe maintain some Docker images for ColdFusion, but no idea where they are or that sort of jazz, so just googled it ("docker coldfusion image"). The first match takes me to "Docker images for ColdFusion", and on there are the exact Docker commands to run CF / code in CF in various ways. What I wanted to do was to run the ColdFusion REPL, and mess around with its config files. The closest option to what I wanted was to run ColdFusions built-in web server to serve a website. I figured it'd use an image with a complete ColdFusion install, so whilst I didn't want or need the web part of it, I could SSH into the container and use the REPL that way. So the option for me was this one:

Run ColdFusion image in daemon mode (that link is just a deep link to the previous one above). That gives the command:

(I've just split that over multiple lines for readability).

Here we're gonna be running the container detached (-d), so once the container runs, control returns to my shell. I'm not at all clear why they're using the pseudo-TTY option here (-t / --tty). From all my reading (basically this Q&A on Stack Overflow: "Confused about Docker -t option to Allocate a pseudo-TTY"), it's more for when not in detached mode?

We're also exposing (publishing) the container's port 8500 to the host. IE: when I make HTTP requests to port 8500 in my PC's browser, it will be routed to the container (and CF's inbuilt web server in the container will be listening).

Lastly on that line we're mounting C:\wwwroot as a volume (-v) in the container as /app. IE: files in my PC's C:\wwwroot dir will be availed within the container in the /app dir.

The second line is just a bunch of environment variables (-e) that get set in the container... the ColdFusion installation process are expecting these I guess.

And the last line is the address of where the CF image is.

I'm not going to use exactly this command actually. I'm on Ubuntu so I don't have a C:\wwwroot, and I don't even care what's in the web root for this exercise (I'm just wanting the REPL, remember), so I'm just going to point it to a temp directory in my home dir (~/tmp). Also I see no reason to enable the secure profile. That's just a pain in the arse. Although it would probably not matter one way or the other.

Also I want to give my container a name (--name) for easy reference.

So here's what I've got:

Let's run that:

This takes a frew minutes to run cos the ColdFusion image is 570MB and it also downloads a bunch of other stuff. As it goes, you see progress like this:

In theory ColdFusion should not be installed and listening on http://localhost:8500, and...

Cool. I've had some issues running the REPL before if the CFAdmin installation step hasn't been run at least once, so I let that go (the password is the one from the environment variable, yeah? ColdFusion123).

I can see the image and the container in docker now too:

Next we need to SSH into the container. For that I'm using some geezer called Jeroen Peters' docker-ssh container. I found this from a bunch of googling, and people saying how not do use SSH from within containers, and instead have the SSH server in a container of its own. Seems legit.

I've modified his docker command slightly to a) point to my cf container, also to detach once it's started:

I can now SSH into the container:

I'm in! Cool!

Just to prove to myself further that I am actually "inside" the container, I jumped over to another bash session on my PC, and stuck a new file in that ~/tmp directory:

And checked it from within the container:

OK so I think I'm happy with that. So... now to run the code...

All this is discussed in the previous article (ColdFusion: looking at an issue Mingo had with ehcache and cachePut and cacheGet). This is showing the problem though... the answer should be 1 not 2

I have to fix this cache setting...

Erm... wat??

Wow OK so this is a really slimmed down container (except the 100s of MB of ColdFusion stuff I mean). I can fix this...

WAAAAAH. OK this is getting annoying now. On a whim I just tried without sudo

Fine. One step forward, one step sideways. Grumble. Another whim:

Ooh! Progress. But... does it work? (hard to get proof of this as vi takes over the shell, but... yes it worked).

I now just have to restart the CF container, and test the fix:

WOOHOO! I managed to do something useful with Docker (and then reproduce it all again when writing this article). Am quite happy about that.

Final thing... if yer reading this and are going "frickin' hell Cameron, you shouldn't do [whatever] like [how I did it]", please let me know. This is very much a learning exercise for me.

Anyhow... this is the most work I've done in about four months now, and I need a... well... another beer.

Righto.

--
Adam

G'day:
I'm trying to re-motivate myself to do some tech type stuff in my spare time. I have a lot of spare time at the moment. 24h of the day. I still haven't really looked for a job having been made redundant a few months back (coughJunecough), and I've been largely wasting my time sleeping, napping (yes, two distinct things), and playing computer games. On one hand 2020 is a bit of a rubbish year, and a new work environment is likely to be a subpar experience, even if I can find work. On the other hand I can afford to not work for quite a while thanks to my redundancy pay out, but on still another hand (yes, fine, I have three hands for the purposes of this story), I really am not taking advantage of this spare time I have. That's why I had a look at Mingo's CF problem the other day ("looking at an issue Mingo had with ehcache and cachePut and cacheGet"). Just trying to do anything marginally "productive".

I've been wanting to learn a bit of Clojure for a while now. Not for any particular reason, and I'm not looking to shift to doing that over PHP, but just cos it's a completely different language from anything I've used before - which have all been C-ish "curly brace" type things - and my mate Sean has banged on about how good it is. I think at his suggestion I bought Living Clojure by Carin Meier a while back when I had some down time in NZ. I read the first few pages and then realised Auckland has a lot of pubs, so did that instead. This would have been about four(?) years ago. I ain't touched it since.

Here I am, sporadically trying to get to grips with Docker, and this seemed like a good mini-project... get Clojure up and running within a container, set up a project, integrate it with an IDE, and get to the point where I have a running (and passing) test for some sort of "G'day world" function. In the past I would install whatever language I was wanting to mess with natively on my PC, but I decided running it in a container is the way to go.

Note that this is pretty much just a record of what I needed to do to get to the point I could write the code and run the tests. I have very little experience with Docker, and hardly any experience with Clojure. What this means is that this is def a newbie account of what I did, and I really would not take it as instructions of how to do stuff. All I will say is that I needed to do a whole bunch of googling to work shit out, and I will summarise the results of the googling here. This is more an exercise for me to verify what I've done actually works, as having done it once... I'm now getting-rid and starting from scratch.

OK. I am starting with a minimal "empty" repo, living-clojure:

This just gives me a directory I can mount in the container to expose my code in there.

Now I need the container. Looking at dockerhub/clojure, the options there are just for running the app, not doing development, so ain't much help. I was hoping to be able to copy and paste something like "a container with Clojure and Leiningen in it wot you can as a shell for building yer project, testing it, developing it, and running it". Nothing to copy and paste and run, so I'm gonna have to work out what to do. Remember I'm a complete noob with Docker.

Getting the image down was easy enough:

(Just showing it mid-pull there)

Just to start with, I just need a container based on the Clojure image, but doing nothing else. I just need to run a shell with it so I can create my Clojure project. I came up with this:

• I'm mounting my host's project directory within the container;
• and setting that to be my working dir in there too;
• I don't completely get these two, but I wanna be able to type shit into my shell that I'm running, and this seems to make it happen;
• and it's bash I want to interact with.

And I start this:

Hurrah! This seems promising: I'm in a different shell, and I'm in the working directory I specified when doing the docker create before.

Let's see if I can create a new Clojure project (which I'm lifting from the the Leiningen docs):

I need to go up a directory level and to use --force because I already have the project directory in place, and lein new assumes one doesn't.

And this all seems to work fine (well… in that it's done "stuff"):

git status shows something interesting though:

Note how .gitignore, LICENSE and README.md have all changed. Such is the price of doing that --force I guess. I'm gonna revert the LICENSE and README.md, but leave the .gitignore; I presume the Leiningen bods have a better idea of what git should ignore in the context of a Clojure project than GitHub's boilerplate one does.

Next… what's the code in the default project actually do?

That will do for a start. Let's see if it runs:

Cool! Is it bad I'm so pleased with a computer saying "Hello, World!"? Ha.

I'm being a bit naughty because I'm running the code before I've tested it. But I figure... not my code, so it's OK. Anyway, there is a test, although it does not test the code in the app. Sigh. But anyhow:

I guess this is in-keeping with "start with a failing test". Fair enough then. At least the test runs correctly, which is good.

The last bit of checking the baseline project is… will it compile and run as a jar?

Perfect.

Right. Now I actually need to write some code. I wanna change that main function to read the first argument from the command-line - if present - and say "G'day [value]" (eg: "G'day Zachary"), or if there's no argument, then stick with just "G'day World".

Given that's all very simple, I could just do it with a text editor, but I'll hook an IDE up to this lot too. I googled around and found that VSCode and the Calva Clojure plug-in. I've already set all that up and can't be arsed redoing it for the purposes of this article. One issue I had… and still have… is that Calva is supposed to be able to connect to an external REPL, instead of using its own one. Whilst experimenting trying to get this working, I tweaked my docker create statement to run a headless REPL instead of bash:

The new stuff is as follows:

• I probably don't need the --expose here for what I'm doing, but the -p exposes the container's port 56505 to the host PC (56505 has no significance… it was just one of the ports a previous REPL had used, so I copied that).
• I start a headless REPL (so basically a REPL as a service, that just listens for REPL connections) that listens on that port 56505
• I have to use 0.0.0.0 here because when I tried to use 127.0.0.1, that worked fine from within the container, but was no good on the host machine. It took me a bit of googling to crack that one.

I start this one without being interactive:

Doing it this way I am exposing a REPL to other sessions, whilst still being able to bash my way along too:

I could get VSCode on my desktop PC to see this REPL:

But I could not get it to do stuff like running tests, which it was able to do using the built-in REPL. So that sucked. I googled a bit and I am not the only person with this problem when using external REPLs, so I have just decided to give up on that. I'll cheat and use the built-in REPL.

Oh god. I now need to write some Clojure code (I've now caught up with my previous progress, and am typing this article "live" now… Bear with me for a bit).

Time passes…

More time passes and there is swearing…

OK, got there. I abandoned using VSCode and Calva because Calva seems to have this strange idea that when I go to delete things (like extra or misplaced parentheses), that it knows better and doesn't just do what it's frickin' told. It's probably me not knowing some special trick that people accustomed to using it know, but… for the love of god if I ask a frickin' text editor to do something in the edit window, I expect it to just do it even if I'm asking it to do something less than ideal. I will seek out a different plugin later. Once I dropped back to using Notepad++, things went better. I have done a lot of googling in the last two hours though. Sigh.

Anyhow, here are my tests:

(ns living-clojure.core-test
  (:require [clojure.test :refer :all]
    [living-clojure.core :refer :all]))

(deftest test-greet-default-behaviour
  (testing "it should return G'day world if no name is passed"
    (is (= "G'day World" (greet [])))))

(deftest test-greet-by-single-name
  (testing "it should return G'day [name] if just that name is passed"
  (is (= "G'day Zachary" (greet ["Zachary"])))))

(deftest test-greet-by-multiple-name
  (testing "it should return G'day [name] if more than one names are passed"
  (is (= "G'day Zachary" (greet ["Zachary" "Cameron" "Lynch"])))))

And here is the code:

(ns living-clojure.core
  (:gen-class))

(defn greet
  ([args]
    (str "G'day " (or (first args) "World"))))

(defn -main
  "I greet someone or everyone"
  [& args]
  (println (greet args)))

And here's the output of the tests, running the code, and compiling and running the code:

I got a bit snagged on the variadic parameters syntax for a while, largely cos to me that just says "it's a reference", so I need to unlearn that in this context. And then cos I've been staring at the screen too long now, I had a brain-disconnect on only the parameters of main were variadic… by the time they got to greet it was just an array (or a list or whatever Clojure calls it). So due to dumbarsey on my part I variously had the tests passing but the behaviour at runtime slightly off, or the tests failing but the program actually running correctly. What this says is that I probably should have been testing main, not greet. My bad.

OK. It's 22:30 and I've been at this on and off for quite a few hours now. I'm pretty pleased with the exercise as a whole - I learned a lot - but now I want to go shoot things. Parentheses. I want to shoot parentheses. But I guess I will settle for shooting raiders in Fall Out 4.

Righto.

--
Adam

G'day:

Firstly some framing. This morning I sat down to do some more Docker stuff, and started to get this issue again:

(I say "again", cos I have been getting this a lot whilst working on another article that's taken me a coupla days to write so far, and won't be done until tomorrow. Note: this issue is not the one I am looking at in this article… I'm looking at that "Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?" issue.)

OK, so enough context. Back to "Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?".

From a lot of googling, most suggestions start with a de-install/re-install Docker Desktop, so decided to try that first. It's important to note that a lot of people had tried this, it had worked for a while, but then it started again. I think it's addressing a symptom not the problem, but I might as well be on the most recent version of Docker Desktop anyhow.

After doing the upgrade I happened to have PhpStorm open, and I absent-mindedly clicked the "refresh" button on the config for the connection to Docker I had. It errored out saying "got no PHP container mate", which was true because the de-install of Docker Desktop got rid of the containers I had. To verify this, I hit the shell:

Erm… OK, that's new. now I had been messing with the Docker daemon settings in Docker Desktop trying to get PhpStorm connecting, so went back in there and re-dis-enabled(!) Docker daemon with no TLS support. I mean this setting:

PhpStorm would stop connecting, but in the mean time I could get my containers up and running. I hit the shell again:

Bugger.

[I said more than bugger this time]

Great. In troubleshooting one issue, I have caused another one. Excellent. Thanks Docker. Thanks me.

After a bunch of googling and restarting randomly and shaking my head at everyone's solution for this issue which seemed to largely be "switch it off and switch it back on again", etc, I landed on someone commenting "weird thing is though… it's all still fine in Powershell. It's just broke in WS". I checked:

Interesting. Something to do with WSL then. Then I remembered a setting I thought seemed odd in Docker Desktop when I gave it the once-over after re-install:

I did not think much of this at the time, because Ubuntu is my default WSL distro, so I figured that was fine. After all… everything had been working fine like that. On a whim, I decided to switch those two toggles back on though:

And now back to bash:

Hurrah. So basically when I de-/re-installed Docker Desktop, it did not maintain its existing settings, and defaulted those two to be off? Weird, but I'm guessing so.

Anyway, no answer I saw via my googlings had this particular solution, so I figrued I'd write it up. This might be obvious to everyone who already knows, but there's enough people out there who clearly don't already know for it to possibly be useful. Perhaps. I'm also not suggesting it's the solution to everyone getting this "Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?" issue, but it's something to check. Ah anyway it's a far easier and quicker article to write than the one I'd been working on. Quick win 'n' all. I'll have the longer article done tomorrow I hope.

Righto.

--
Adam

 G'day:

I'm still beavering away getting a PHP dev environment working via Docker. As I mentioned in the previous article, I'm writing an article about how I'm doing that as I go, but I've had a few issues today that have made me pause that.

My current issue has been getting PHPUnit working properly. This has nothing to do with the Docker environment (as far as I can tell), it's just... me and PHPUnit not playing nicely together. The solution to my issue was not immediately apparent to me... it's taken me about three hours to sort this out. So I figured it might be worthwhile writing down.

I have a barebones "G'day World" website running in a coupla Docker containers (one for Nginx, one for PHP). That's all working fine, I can get "G'day world" being delivered to the browser via both HTML and PHP requests. Before I start writing any really-really code, I decided I better get PHPUnit working. TDD 'n' all that. I will admit I felt dirty yesterday when I wrote the gdayWorld.html and gdayWorld.php and ran them without tests; I just browsed to them and went "seems legit". Not the way I like to operate.

I sat down to write some tests. My gdayWorld.php is... basic:

<?php

$message = "G'day World";
echo $message;

I don't have any framework or anything installed as yet, so that's as good as it gets. That is in the web root. To test that I'd be needing to test that by curling it and checking the response, then I remembered Symfony has a WebTestCase for this sort of thing, then I decided I could not be arsed looking into that right now. All I need is a test to run to check PHPUnit is running. So... erm... here we go:

    /** @coversNothing */
    public function testNothing()
    {
        $this->assertTrue(false);
    }

This is enough to test PHPUnit. I'll write a better test once I know everything is working.

Perfect. Now I can make it pass ;-)

$this->assertTrue(true);

So far, so good. My next step whilst I'm configuring stuff on PHPUnit, I decided to get the code coverage working too. I just added the code-coverage reporting bit to phpunit.xml and re-ran the tests:

Doh! Forgot about that. I need to install Xdebug.

This was way more horsing around than it could have been, but this is down to the vagaries of the Docker set-up I was using. Once I decided to change direction it was a one-liner in me Dockerfile, and all good.

Run the tests again...

OK. Fine. Makes sense I s'pose. I added in the ini setting into my phpunit.xml:

<php>
<ini name="xdebug.mode" value="coverage" />
</php>

No difference. I figured the ini setting is probably changed too late in the piece, as the xdebug.mode will need to be set before PHP starts running any code. And perhaps the environment variable approach would work such that the actual environment variable was set before hand. As it happens it ain't - all that happens is the value is added to the $_ENV array, which is hardly the same thing. From the docs:

However this step is still a relevant one cos we see a behavioural change here:

Splat!

I'm gonna spare you a coupla hours of looking in to how to troubleshoot segmentation faults here. Nothing I read helped, and there's nothing useful relating to getting them with PHPUnit, other than a bunch of people getting these segmentation faults.

I started to wonder if it was an issue with Xdebug and PHP8, given PHP8 is so new and sometimes in the last I've noted that Xdebug has needed updating when there's a point release of PHP. But looking into this (at Xdebug: Supported Versions and Compatibility), the current version of Xdebug has been around for a while, and they say it's good to go with PHP8:

I was now thinking about versions of stuff, so I decided to rollback PHP to 7.4, and PHPUnit to 8.5. I realise I should have only done one at a time, but it did not occur to me when doing this that when troubleshooting things, only change one thing per test iteration.

This verifies we are back to PHP 7.4 and PHPUnit 8.5. And we don't have the segmentation fault any more, but... now PHP is ignoring both of the settings in phpunit.xml. I have this in place:

<php>
<env name="XDEBUG_MODE" value="coverage"/>
<ini name="xdebug.mode" value="coverage"/>
</php>

At this point I read up on the <ini> and <env> settings in phpunit.xml, and confirmed both of them are set too late for Xdebug to read them anyhow. Quite odd the way PHPUNit 9.5 reacts to the XDEBUG_MODE being set in that case. Anyway, I need to set them before PHP is run, so I set a really-really environment variable in my Dockerfile:

ENV XDEBUG_MODE=coverage

After rebuilding my containers:

Hurrah! Let's have a look at the report:

This is correct: I'm not testing that code in /public yet.

I also quickly tried to use the xdebug.mode ini file setting. I dropped a /usr/local/etc/php/conf.d/phpunit-code-coverage-xdebug.ini with just xdebug.mode=coverage in it into my container's file system:

Perfect.

My supposition here is that the issue all along was that I needed to set one of either the ini file option, or the environment variable option before PHPUnit runs. PHPUnit 8 correctly sez "OI!" if I don't; whereas PHPUnit 9 doesn't check correctly, and instead messes things up. Let's roll forward to PHP8 and PHPUnit 9.5 again and see:

Hoo-frickin-ray!!

So that supposition was correct then.

I guess I could have saved myself a bunch of time here by just setting the .ini setting or the environment variable in the correct environment right from the outset. Then again had PHPUnit 9 not changed its warnings, I would have known that straight away: PHPUnit 8 was pretty clear on this. The problem and the solution here were pretty mundane, but I learned a lot about how to do things with Docker (which will all go into the other article I'm writing at the same time as this one), some stuff about Xdebug, some stuff about PHP and some stuff about PHPUnit. So it was a worthwhile afternoon of scratching my head. I'm also pleased I've sat here and done 8hrs of "work" for the second day running. Hopefully this will stick and I'll work my way out of my unemployed malaise before long. We'll see.

Anyway... now for a beer.

Righto.

--
Adam