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[[Category:Miniature]]
This is a list of things we agreed upon in the Miniature team.
TODO: List the items that are *not* fully agreed upon yet!!

= License =
Miniature will use the [http://www.gnu.org/licenses/gpl-2.0.html GPL 2 (or later)] for source and header files. For art contribution, Miniature will use the [http://creativecommons.org/licenses/by-sa/3.0/ CC-by-sa].

= Coding style =
We do not need project-wide consistency, but be at least consistent inside a module and/or file.

Note: the current code violates this style. We will fix it.

We mostly <s>try to follow the offical Qt Coding Guidelines, but with some exceptions.</s> follow mikhas' personal coding style for Qt:
* We use whitespaces over tabs.
* Max. length of a source code line is 120 characters.
* We use a Miniature namespace for all our components, and all our types(classes + typedefs) start with M.
** Exception: value types (containers, flags) start with a lowercase m, for example mMoveFlags or mHalfMove. Value types are useful when you need copy construction and copy assignment. In general though, objects are *not* copyable! MPosition is the biggest violation to this rule, feel free to fix it!
* Types are in MCamelCase, unless they are mValueTypes (see above).
* Method names are in mixedCase (= lowerCamelCase).
* Braces after newlines.
* Variable names should be visually different from types (even if you use an editor w/o syntax highlighting), there_fore they have under_scores, no caps, no lower_Camel_Case.
* Member variables should be visible, even if your editor does not highlight member variables for you. That's why we prefix them with m_*.
* We use no_keywords, for now. We want to avoid those function-style macros.
* Impl files have a .cc extensions, header files use .h
* Use Qt containers over std containers.

== Naming conventions ==

* Methods *do* something, that's why their names should always contain a verb (slots and signals count as methods, too).

* typedef'd types *might* hint at their composed types (to emphasize their intended use), but avoid directly including the type information in the name:

typedef QSharedPointer<SomeClass> SomeSharedClass; // Good! Sharing a resource is a concept.
  typedef QSharedPointer<SomeClass> SomeClassPtr; // Bad! What is a "SomeClassPtr *some_variable" now?

typedef QList<SomeClass> SomeClassList; // still OK, since "List" is a concept, too.

* Avoid hungarian variable names.

== Advanced coding style ==

* Signal and slot connections should be easy to read, as they are a constant source of bugs:

connect(some_signal_source, SIGNAL(theSignalWasEmitted()),
          some_receiver,      SLOT(onTheSignalWasEmitted()),
          Qt::UniqueConnection);

** Details:
*** slots should follow the signal's name, if possible (slot prefix: on*).
*** Indentation is one line for the source/signal, one for the receiver/slot and another one for the connection type.
*** SIGNAL and SLOT should start in the same column (together with the slot's name prefix it will neatly align the parameters etc.).
*** Use normalized signal/slot signatures (no const keyword, no &).
*** Use Qt::UniqueConnection for the connection type (it's *not* the default connection type), since most of the time, it is exactly what you want. A double connection between the same source/receiver and SIGNAL/SLOT is often a bug, and this can lead to weird behaviour if the same connection code is called over and over again, leading to what I call "connection leaks". With Qt::UniqueConnection, you clearly state the intent of the connection type, while also preventing those connection leaks.

* Method parameters in header files (*not* needed in impl files) should be easy to read:

class SomeClass
  {
      void someMethod(SomeType arg1,
                      SomeOtherType arg2,
                      ...);

** Details:
*** Move each argument to a new line. This serves two goals: header files will be easier to scan (for humans), and you'll spot those ugly methods that scream "refactor me!" faster because they have more than 3 arguments. Also, because it *is* ugly, you might just go and refactor it, which will help everyone.

* Use const refs for arguments when possible, even if the type is COW (copy-on-write, for example QString).

* Conditionals
** One line before and after conditional blocks, to visually separate it from the surrounding code.
** It is OK for single-line conditional blocks to omit the braces (because of the extra newlines).
** && and || belong on the next line, if the condition needs to be wrapped (indented by 4 spaces). Put braces around complex conditions, to logically group them together (and to prevent operator precendence bugs, too):

if ((something && somethingElse)
       || orPerhapsThis)
      ...

** Details:
*** Conditionals often contain bugs. Especially when the surrounding code gets refactored, those bugs simply slip in.
*** If a conditional needs to be wrapped, it starts to look ugly. Good! It might lead you to refactor the code, moving the condition itself into a predicate function (which has the nice effect to serve as a comment, if it has a good name).
*** Nested conditionals quickly start to look ugly with all those line separators, but you probably guessed it already: It's just another sign that this code might need some cleanup! Nested conditionals should be used rarely or hidden within dedicated methods.

* One space after keywords that could be mistaken as functions (if, for, ...).

* If you store a pointer to an object over which you do not intend to take ownership, then wrap this pointer in a QPointer:

class SomeOtherClass
  {
      QPointer<SomeType> m_member;
  }

** Details:
*** QPointers keep track of object deletion and set all referring QPointers to zero, preventing dangling pointers. Especially when using signals & slots, this is an often (and sometimes hard to spot!) source of bugs. With QPointers, you can wrap your code with conditional guards like so:

if (m_member)
  {
      // Do sth with m_member object.
      // This block *never* gets executed even if m_member was deleted elsewhere.
  }

* Assign 0 to pointers after deletion (or use QPointers).
* Always initialize type primitives (e.g., pointers) in the constructor's initializer list.

== How to keep code testable (and hopefully, mostly bugfree) ==
We want to have testable code, therefore we also want to follow some advanced coding standards.

For that, I will try to list some really really useful advice from this document: http://www.research.att.com/~bs/JSF-AV-rules.pdf, a coding style document for C++. Bjarne Stroustrup worked on that one, yes.
 
* Keep methods at a reasonable length. In general: If it doesn't fit on a screen page it's probably too long. More precise: Every method longer than 200 lines of code (including comments, yes) is too long.
* Within a method, avoid a cyclomatic complexity higher than 20 (see Appendix A regarding AV Rule 3, pp. 65, "Cyclomatic complexity measures the amount of decision logic in a single software module.", and the example).
* Avoid cyclic dependencies between classes/modules (Rationale: it's mostly an indicator for layer violations).

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Editing Miniature/Policies

@@ Line 100: / Line 100: @@
 * Assign 0 to pointers after deletion (or use QPointers).
 * Always initialize type primitives (e.g., pointers) in the constructor's initializer list.
-* Don't use forward declaration unless necessary. It is not your task to optimize the compiler. Also, Qt Creator gets confused by them.
 == How to keep code testable (and hopefully, mostly bugfree) ==