PHPcon Poland - Static Analysis of PHP Code – How the Heck did I write so many Bugs?
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Static analysis tools can analyze code without executing it to find bugs and issues. The document discusses several static analysis tools for PHP like PHPMD, Phan, PHPCS, PHPLOC, Deptrac. It explains what they do, like PHPLOC gathering complexity metrics and Deptrac checking for violations of defined layer dependencies. In the end, it recommends using static analysis in CI and not trusting results blindly without understanding the underlying errors.
![deptrac is alpha, not production ready.
please help us and report feedback / bugs.
Start to create an AstMap for 24 Files.
........................
AstMap created.
start emitting dependencies "InheritanceDependencyEmitter"
start emitting dependencies "BasicDependencyEmitter"
end emitting dependencies
start flatten dependencies
end flatten dependencies
collecting violations.
formatting dependencies.
[...]ServicesPdfOrder::5 must not depend on [...]EntityVorkursticket (Service on Enti
[...]ServicesPdfOrder::23 must not depend on [...]EntityVorkursticket (Service on Ent
Found 2 Violations](https://image.slidesharecdn.com/staticanalysisofphpcodehowtheheckdidiwritesomanybugs-161002104123/85/PHPcon-Poland-Static-Analysis-of-PHP-Code-How-the-Heck-did-I-write-so-many-Bugs-45-320.jpg)
![class ContentType
{
/**
* The fields, keyed by ID.
*
* @var object
*/
private $fields = [];
}
src/Delivery/ContentType.php:34 PhanTypeMismatchProperty Assigning array to
property but contentfuldeliverycontenttype::fields is object](https://image.slidesharecdn.com/staticanalysisofphpcodehowtheheckdidiwritesomanybugs-161002104123/85/PHPcon-Poland-Static-Analysis-of-PHP-Code-How-the-Heck-did-I-write-so-many-Bugs-52-320.jpg)
PHPcon Poland - Static Analysis of PHP Code – How the Heck did I write so many Bugs?
- 1. Static Analysis of PHP Code How the Heck did I write so many Bugs? PHPCon Poland, September 2016 By Rouven Weßling ( ) Ecosystem Developer / Developer Evangelist, Contentful @RouvenWessling photo credit: byWarsaw Kamil Porembiński (license)
- 2. A content management developer platform with an API at its core.
- 5. Dynamic Analysis xdebug xhprof PHP Analyzer PHP Vulnerability Hunter Assertions
- 7. Spend less time on unit tests...
- 10. class ClientTest extends PHPUnit_Framework_TestCase { public function testGetSynchronizationManager() { $client = new Client('b4c0n73n7fu1', 'cfexampleapi'); $this->assertInstanceOf(Manager::class, $client->getSynchronizationManager()); } }
- 11. Easy to integrate in Continuous Integration
- 13. Find issues that can not be found through unit tests
- 14. PHP 7 Abstract Syntax Tree Scalar Types Strict Types
- 15. PHP is dynamic Reflection Variable variables Referencing classes/functions/properties by string
- 16. The more static your code is, the easier it's to reason about.
- 17. Some tools
- 18. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter RIPS Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 19. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter RIPS Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 20. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter RIPS Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 21. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter RIPS Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 22. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter RIPS Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 23. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 24. phpmd phan phpcs phpunit phploc phpcpd phpsa php7c Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 25. phpmd phan phpcs phpunit phploc phpcpd phpsa PHP Coupling Detector Mondrian PHP Assumption PhpCodeAnalyzer PHPCodeFixer php7mar PH Semantic Versioning Checker PHP Inspection PHP lint PHP Depend PhpMetrics PHPCheckstyle PHP Reaper PHP vuln hunter Parse SonarQube Side Channel Analyzer TaintPHP Deptrac PhpDependencyAnalysis PHP semver checker
- 26. PHP lint php -l
- 28. Compiles PHP script with the actual PHP compiler It's already installed on your computer Can be used to test compatibility with multiple PHP versions
- 29. <?php namespace ContentfulLog use PsrHttpMessageRequestInterface; use PsrHttpMessageResponseInterface; class NullLogger implements LoggerInterface { public function getTimer() { return new NullTimer; } public function log($api, RequestInterface $request, StandardTimer $timer, Respons { } }
- 30. PHP 7.0.3 | 10 parallel jobs .................................X...... 40/40 (100 %) Checked 40 files in 0.5 seconds Syntax error found in 1 file ------------------------------------------------------------ Parse error: src/Log/NullLogger.php:9 7| namespace ContentfulLog 8| > 9| use PsrHttpMessageRequestInterface; 10| use PsrHttpMessageResponseInterface; 11| Unexpected 'use' (T_USE), expecting '{'
- 31. Make your life easier Use PHP-Parallel-Lint
- 32. phploc
- 33. Gather stats about your projects Get an idea of the complexity See long term trends
- 34. phploc 3.0.1 by Sebastian Bergmann. Directories 6 Files 40 Size Lines of Code (LOC) 5683 Comment Lines of Code (CLOC) 2562 (45.08%) Non-Comment Lines of Code (NCLOC) 3121 (54.92%) Logical Lines of Code (LLOC) 951 (16.73%) Classes 868 (91.27%) Average Class Length 21 Minimum Class Length 0 Maximum Class Length 190 Average Method Length 2 Minimum Method Length 0 Maximum Method Length 25 Functions 0 (0.00%) Average Function Length 0 Not in classes or functions 83 (8.73%)
- 35. Cyclomatic Complexity Average Complexity per LLOC 0.28 Average Complexity per Class 7.65 Minimum Class Complexity 1.00 Maximum Class Complexity 62.00 Average Complexity per Method 1.82 Minimum Method Complexity 1.00 Maximum Method Complexity 11.00
- 36. If you're getting serious about Cyclomatic Complexity, use phpmd.
- 37. Dependencies Global Accesses 0 Global Constants 0 (0.00%) Global Variables 0 (0.00%) Super-Global Variables 0 (0.00%) Attribute Accesses 536 Non-Static 535 (99.81%) Static 1 (0.19%) Method Calls 319 Non-Static 308 (96.55%) Static 11 (3.45%)
- 38. Structure Namespaces 7 Interfaces 3 Traits 0 Classes 37 Abstract Classes 3 (8.11%) Concrete Classes 34 (91.89%) Methods 272 Scope Non-Static Methods 272 (100.00%) Static Methods 0 (0.00%) Visibility Public Methods 221 (81.25%) Non-Public Methods 51 (18.75%) Functions 6 Named Functions 0 (0.00%) Anonymous Functions 6 (100.00%) Constants 2 Global Constants 0 (0.00%) Class Constants 2 (100.00%)
- 39. Deptrac
- 40. Software has layers There should be rules about those layers Rules are easily broken
- 41. 1. Define the layers of your architecture 2. Define what layers another layer can access 3. Profit!!!
- 42. layers: - name: Controller collectors: - type: className regex: .*Controller.* - name: Entity collectors: - type: className regex: AstaRwthVorkursticketBundleEntity.*
- 43. ruleset: Controller: - Service - Entity - Form Service: - Repository Command: - Entity Entity: - Validator
- 44. How it works Parses all files in your code Stores which classes access which others classes Checks the graph for rule violations
- 45. deptrac is alpha, not production ready. please help us and report feedback / bugs. Start to create an AstMap for 24 Files. ........................ AstMap created. start emitting dependencies "InheritanceDependencyEmitter" start emitting dependencies "BasicDependencyEmitter" end emitting dependencies start flatten dependencies end flatten dependencies collecting violations. formatting dependencies. [...]ServicesPdfOrder::5 must not depend on [...]EntityVorkursticket (Service on Enti [...]ServicesPdfOrder::23 must not depend on [...]EntityVorkursticket (Service on Ent Found 2 Violations
- 47. phan
- 49. Type safety for PHP Checks docblocks Signature mismatches Unused code
- 50. How it works Makes 2 passes over the codebase 1. Build a list of all classes, functions, methods, etc. 2. Go trough each function and follow the type of each variable
- 51. /** * @param Locale|string|null $locale * * @return string */ public function getDescription($locale = null) { $localeCode = $this->getLocaleFromInput($locale); // This checks happens after the call to getLocaleFromInput to make sure // the Exception for invalid locales is still thrown. if ($this->description === null) { return null; } return $this->description->$localeCode; } src/Delivery/Asset.php:74 PhanTypeMismatchReturn Returning type null but getDescription() is declared to return string
- 52. class ContentType { /** * The fields, keyed by ID. * * @var object */ private $fields = []; } src/Delivery/ContentType.php:34 PhanTypeMismatchProperty Assigning array to property but contentfuldeliverycontenttype::fields is object
- 53. public function __call($name, $arguments) { // Lots of code here if ($result instanceof Link) { return $client->resolveLink($result); } return array_map(function ($value) use ($client) { if ($value instanceof Link) { return $client->resolveLink($value); } return $value; }, $result); } src/Delivery/DynamicEntry.php:126 PhanTypeMismatchArgumentInternal Argument 2 (input1) is contentfuldeliverylink but array_map() takes array Not a bug
- 55. Bad news? Requires php-ast Not easy to deal with library code Noisy - not easily integrated in CI.
- 56. The future
- 57. phan is using brute force for type checking Roughly as good as the compiler for a statically typed language Works, but a Control Flow Graph could give even deeper insight
- 58. int foo(int length) { int x = 0; for (int i = 0; i < length; i++) x += 1 return length/x; }
- 60. Bottom line There are dozens of tools - pick what's necessary for you Make them part of your Continuous Integration setup Never trust. Make sure you understand where the error is coming from.
- 62. Slides available on Slideshare: http://www.slideshare.net/rwessling Please leave feedback on joind.in ( ) or tweet me ( ) https://joind.in/talk/8f19b @RouvenWessling