Developer-Guide/standards/general.md

# Code Standards

The term "class" refers to all classes, interfaces, and traits. These standards only show how the code should look like and doesn't give examples of bad code.

## Side Effects

A file SHOULD declare new symbols (classes, functions, constants, etc.) and cause no other side effects, or it SHOULD execute logic with side effects, but SHOULD NOT do both.

The phrase "side effects" means execution of logic not directly related to declaring classes, functions, constants, etc., merely from including the file.

"Side effects" include but are not limited to: generating output, explicit use of require or include, connecting to external services, modifying ini settings, emitting errors or exceptions, modifying global or static variables, reading from or writing to a file, and so on.

## Character Encoding

PHP code MUST use only UTF-8 without BOM

## Line Ending

Lines MUST end with `\n` (LF) and MUST NOT have a whitespace at the end.

## File Ending

Files must end with a new line element `\n`.

## Member variables

Member variables should be public unless there is absolutely no reason to directly access them or additional data manipulation upon setting, changing or returning them is required.

### Getters/Setters

Getters and setters for member variables should be kept at a absolute minimum and only used when they actually perform additional actions.

### Why are we using public so much?

* Private/protected adds a huge amount of unnecessary typing without gaining much/anything
* Getters/setters may hide unsuspecting side effects
* Adding additional functionality afterwards if it becomes necessary is easy by changing the member to private and letting the static code inspection tools find the callers
* Performance overhead (function calls, data mappers)
* Private or protected doesn't add any security due to unserialization and reflections

## Indention

The default indention MUST be 4 spaces.

## Spacing

### Enumerations

Always use a whitespace **after**:

* `,`
* `;` (unless at the end of a line)

### Operators

Always use a whitespace **before** and **after**:

* assignment (e.g. `=`, `=>`, `+=`, `/=`, `*=`, `-=`, `.=`)
* math operations (e.g. `+`, `-`, `*`, `/`, `%`, `&`, `|`, `**`, `>>`, `<<`)
* logic operators (e.g. `&&`, `||`)
* comparison (e.g. `==`, `===`, `>`, `>=`, `<`, `<=`)

### Other

Never use spaces between variables and atomic operations (e.g. `!`, `++`, `--`)

### Parentheses

Don't use whitespace inside ANY parentheses (e.g. functions, loops, conditions, catch, closures).

```js
for (let i = 1; i < 100; ++i) {
    ...
}
```

```js
function(para1, para2) {
    ...
}
```

### Brackets

Don't use whitespace inside ANY brackets.

```php
$arr = [1, 2, 3];
```

### Braces

Always use a whitespace between braces and keywords (e.g. else, while, catch, finally) and parentheses

```php
try {
    ...
} catch (...);
```

```php
if (...) {
    ...
} else (...);
```

Braces are on the same line as the previous or following keyword except in classes and functions.

```php
function()
{
    ...
}
```

```php
class Test
{
    ...
}
```

### If, while, for, foreach, switch

Always use a whitespace before the parentheses.

```php
while (true) {
    ...
}
```

## If, while, for, foreach, switch

Always use braces even for potential one liners. The only exception is the ternary operator.

```php
if (...) {
    ...
}
```

```php
$result = condition ? expr1 : expr2;
```

Multiline ternary expressions should be indented.


```php
$result = condition
    ? very long expr1 which should be written like this
    : very long expr2 which should be written like this;
```

Multiline `if` conditions should begin with a logical operator `or`/`and`.

```php
if (isTrue == true
    || isFalse === false
    && isNotTrue !== true
) {
    ...
}
```

Switch statements must have a `default` case.

## Naming

### Constants

Constants must have a visibility defined if possible (private, public, protected) and must be written with capital letters and snake case.

```php
public CONSTANT_TEST = true;
```

### Function

Functions must be written in camelCase.

### Variables

Variables must be written in camelCase.

#### Boolean variables

Boolean variable names should start with a boolean expression (e.g. is, has)

##### Boolean return value

Functions which return a boolean value should start with expressions such as is*, has* or similar expressions to indicate that the function returns a boolean value.

### Database

#### Tables

Tables must be written in snake_case

#### Fields / Columns

Fields/columns must be written in snake_case and must be preceded by the table name.

```sql
table_name_field_name
```

This allows every field/column name to be unique.

## Quotation

All string representations should use single quotes `''` unless `""` provides significant benefits in a specific use case.

```js
'This is a string'
```