Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like ConvertExtensionToRegistration often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use ConvertExtensionToRegistration, and based on these observations, apply Extract Interface, too.
1 | <?php |
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5 | class ConvertExtensionToRegistration extends Maintenance { |
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6 | |||
7 | protected $custom = [ |
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8 | 'MessagesDirs' => 'handleMessagesDirs', |
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9 | 'ExtensionMessagesFiles' => 'handleExtensionMessagesFiles', |
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10 | 'AutoloadClasses' => 'removeAbsolutePath', |
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11 | 'ExtensionCredits' => 'handleCredits', |
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12 | 'ResourceModules' => 'handleResourceModules', |
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13 | 'ResourceModuleSkinStyles' => 'handleResourceModules', |
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14 | 'Hooks' => 'handleHooks', |
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15 | 'ExtensionFunctions' => 'handleExtensionFunctions', |
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16 | 'ParserTestFiles' => 'removeAbsolutePath', |
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17 | ]; |
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18 | |||
19 | /** |
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20 | * Things that were formerly globals and should still be converted |
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21 | * |
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22 | * @var array |
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23 | */ |
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24 | protected $formerGlobals = [ |
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25 | 'TrackingCategories', |
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26 | ]; |
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27 | |||
28 | /** |
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29 | * No longer supported globals (with reason) should not be converted and emit a warning |
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30 | * |
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31 | * @var array |
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32 | */ |
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33 | protected $noLongerSupportedGlobals = [ |
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34 | 'SpecialPageGroups' => 'deprecated', // Deprecated 1.21, removed in 1.26 |
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35 | ]; |
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36 | |||
37 | /** |
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38 | * Keys that should be put at the top of the generated JSON file (T86608) |
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39 | * |
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40 | * @var array |
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41 | */ |
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42 | protected $promote = [ |
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43 | 'name', |
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44 | 'namemsg', |
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45 | 'version', |
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46 | 'author', |
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47 | 'url', |
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48 | 'description', |
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49 | 'descriptionmsg', |
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50 | 'license-name', |
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51 | 'type', |
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52 | ]; |
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53 | |||
54 | private $json, $dir, $hasWarning = false; |
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55 | |||
56 | View Code Duplication | public function __construct() { |
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57 | parent::__construct(); |
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58 | $this->addDescription( 'Converts extension entry points to the new JSON registration format' ); |
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59 | $this->addArg( 'path', 'Location to the PHP entry point you wish to convert', |
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60 | /* $required = */ true ); |
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61 | $this->addOption( 'skin', 'Whether to write to skin.json', false, false ); |
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62 | $this->addOption( 'config-prefix', 'Custom prefix for configuration settings', false, true ); |
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63 | } |
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64 | |||
65 | protected function getAllGlobals() { |
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71 | |||
72 | public function execute() { |
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73 | // Extensions will do stuff like $wgResourceModules += array(...) which is a |
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74 | // fatal unless an array is already set. So set an empty value. |
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75 | // And use the weird $__settings name to avoid any conflicts |
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76 | // with real poorly named settings. |
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77 | $__settings = array_merge( $this->getAllGlobals(), array_keys( $this->custom ) ); |
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78 | foreach ( $__settings as $var ) { |
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79 | $var = 'wg' . $var; |
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80 | $$var = []; |
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81 | } |
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82 | unset( $var ); |
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83 | $arg = $this->getArg( 0 ); |
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84 | if ( !is_file( $arg ) ) { |
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85 | $this->error( "$arg is not a file.", true ); |
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86 | } |
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87 | require $arg; |
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88 | unset( $arg ); |
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89 | // Try not to create any local variables before this line |
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90 | $vars = get_defined_vars(); |
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91 | unset( $vars['this'] ); |
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92 | unset( $vars['__settings'] ); |
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93 | $this->dir = dirname( realpath( $this->getArg( 0 ) ) ); |
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94 | $this->json = []; |
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95 | $globalSettings = $this->getAllGlobals(); |
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96 | $configPrefix = $this->getOption( 'config-prefix', 'wg' ); |
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97 | if ( $configPrefix !== 'wg' ) { |
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98 | $this->json['config']['_prefix'] = $configPrefix; |
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99 | } |
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100 | foreach ( $vars as $name => $value ) { |
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101 | $realName = substr( $name, 2 ); // Strip 'wg' |
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102 | if ( $realName === false ) { |
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103 | continue; |
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104 | } |
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105 | |||
106 | // If it's an empty array that we likely set, skip it |
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107 | if ( is_array( $value ) && count( $value ) === 0 && in_array( $realName, $__settings ) ) { |
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108 | continue; |
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109 | } |
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110 | |||
111 | if ( isset( $this->custom[$realName] ) ) { |
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112 | call_user_func_array( [ $this, $this->custom[$realName] ], |
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113 | [ $realName, $value, $vars ] ); |
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114 | } elseif ( in_array( $realName, $globalSettings ) ) { |
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115 | $this->json[$realName] = $value; |
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116 | } elseif ( array_key_exists( $realName, $this->noLongerSupportedGlobals ) ) { |
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117 | $this->output( 'Warning: Skipped global "' . $name . '" (' . |
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118 | $this->noLongerSupportedGlobals[$realName] . '). ' . |
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119 | "Please update the entry point before convert to registration.\n" ); |
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120 | $this->hasWarning = true; |
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121 | } elseif ( strpos( $name, $configPrefix ) === 0 ) { |
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122 | // Most likely a config setting |
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123 | $this->json['config'][substr( $name, strlen( $configPrefix ) )] = [ 'value' => $value ]; |
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124 | } elseif ( $configPrefix !== 'wg' && strpos( $name, 'wg' ) === 0 ) { |
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125 | // Warn about this |
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126 | $this->output( 'Warning: Skipped global "' . $name . '" (' . |
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127 | 'config prefix is "' . $configPrefix . '"). ' . |
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128 | "Please check that this setting isn't needed.\n" ); |
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129 | } |
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130 | } |
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131 | |||
132 | // check, if the extension requires composer libraries |
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133 | if ( $this->needsComposerAutoloader( dirname( $this->getArg( 0 ) ) ) ) { |
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134 | // set the load composer autoloader automatically property |
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135 | $this->output( "Detected composer dependencies, setting 'load_composer_autoloader' to true.\n" ); |
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136 | $this->json['load_composer_autoloader'] = true; |
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137 | } |
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138 | |||
139 | // Move some keys to the top |
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140 | $out = []; |
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141 | foreach ( $this->promote as $key ) { |
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142 | View Code Duplication | if ( isset( $this->json[$key] ) ) { |
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143 | $out[$key] = $this->json[$key]; |
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144 | unset( $this->json[$key] ); |
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145 | } |
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146 | } |
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147 | $out += $this->json; |
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148 | // Put this at the bottom |
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149 | $out['manifest_version'] = ExtensionRegistry::MANIFEST_VERSION; |
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150 | $type = $this->hasOption( 'skin' ) ? 'skin' : 'extension'; |
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151 | $fname = "{$this->dir}/$type.json"; |
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152 | $prettyJSON = FormatJson::encode( $out, "\t", FormatJson::ALL_OK ); |
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153 | file_put_contents( $fname, $prettyJSON . "\n" ); |
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154 | $this->output( "Wrote output to $fname.\n" ); |
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155 | if ( $this->hasWarning ) { |
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156 | $this->output( "Found warnings! Please resolve the warnings and rerun this script.\n" ); |
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157 | } |
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158 | } |
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159 | |||
160 | protected function handleExtensionFunctions( $realName, $value ) { |
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177 | |||
178 | View Code Duplication | protected function handleMessagesDirs( $realName, $value ) { |
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185 | |||
186 | protected function handleExtensionMessagesFiles( $realName, $value, $vars ) { |
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200 | |||
201 | private function stripPath( $val, $dir ) { |
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211 | |||
212 | View Code Duplication | protected function removeAbsolutePath( $realName, $value ) { |
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219 | |||
220 | protected function handleCredits( $realName, $value ) { |
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230 | |||
231 | public function handleHooks( $realName, $value ) { |
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232 | foreach ( $value as $hookName => &$handlers ) { |
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233 | if ( $hookName === 'UnitTestsList' ) { |
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234 | $this->output( "Note: the UnitTestsList hook is no longer necessary as " . |
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235 | "long as your tests are located in the \"tests/phpunit/\" directory. " . |
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236 | "Please see <https://www.mediawiki.org/wiki/Manual:PHP_unit_testing/" . |
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237 | "Writing_unit_tests_for_extensions#Register_your_tests> for more details.\n" |
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238 | ); |
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239 | } |
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240 | foreach ( $handlers as $func ) { |
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241 | if ( $func instanceof Closure ) { |
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242 | $this->error( "Error: Closures cannot be converted to JSON. " . |
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243 | "Please move the handler for $hookName somewhere else.", 1 |
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244 | ); |
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245 | } |
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246 | // Check if $func exists in the global scope |
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247 | if ( function_exists( $func ) ) { |
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248 | $this->error( "Error: Global functions cannot be converted to JSON. " . |
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249 | "Please move the handler for $hookName inside a class.", 1 |
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250 | ); |
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251 | } |
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252 | } |
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253 | if ( count( $handlers ) === 1 ) { |
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254 | $handlers = $handlers[0]; |
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255 | } |
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256 | } |
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257 | $this->json[$realName] = $value; |
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258 | } |
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259 | |||
260 | protected function handleResourceModules( $realName, $value ) { |
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291 | |||
292 | protected function needsComposerAutoloader( $path ) { |
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304 | } |
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305 | |||
308 |
The PSR-1: Basic Coding Standard recommends that a file should either introduce new symbols, that is classes, functions, constants or similar, or have side effects. Side effects are anything that executes logic, like for example printing output, changing ini settings or writing to a file.
The idea behind this recommendation is that merely auto-loading a class should not change the state of an application. It also promotes a cleaner style of programming and makes your code less prone to errors, because the logic is not spread out all over the place.
To learn more about the PSR-1, please see the PHP-FIG site on the PSR-1.