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 QRCode 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 QRCode, and based on these observations, apply Extract Interface, too.
1 | <?php |
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22 | class QRCode{ |
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23 | |||
24 | /** |
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25 | * API constants |
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26 | */ |
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27 | const OUTPUT_STRING_TEXT = 'txt'; |
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28 | const OUTPUT_STRING_JSON = 'json'; |
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29 | |||
30 | const OUTPUT_MARKUP_HTML = 'html'; |
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31 | const OUTPUT_MARKUP_SVG = 'svg'; |
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32 | # const OUTPUT_MARKUP_XML = 'xml'; // anyone? |
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33 | |||
34 | const OUTPUT_IMAGE_PNG = 'png'; |
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35 | const OUTPUT_IMAGE_JPG = 'jpg'; |
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36 | const OUTPUT_IMAGE_GIF = 'gif'; |
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37 | |||
38 | const ERROR_CORRECT_LEVEL_L = 1; // 7%. |
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39 | const ERROR_CORRECT_LEVEL_M = 0; // 15%. |
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40 | const ERROR_CORRECT_LEVEL_Q = 3; // 25%. |
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41 | const ERROR_CORRECT_LEVEL_H = 2; // 30%. |
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42 | |||
43 | // max bits @ ec level L:07 M:15 Q:25 H:30 % |
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44 | const TYPE_01 = 1; // 152 128 104 72 |
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45 | const TYPE_02 = 2; // 272 224 176 128 |
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46 | const TYPE_03 = 3; // 440 352 272 208 |
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47 | const TYPE_04 = 4; // 640 512 384 288 |
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48 | const TYPE_05 = 5; // 864 688 496 368 |
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49 | const TYPE_06 = 6; // 1088 864 608 480 |
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50 | const TYPE_07 = 7; // 1248 992 704 528 |
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51 | const TYPE_08 = 8; // 1552 1232 880 688 |
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52 | const TYPE_09 = 9; // 1856 1456 1056 800 |
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53 | const TYPE_10 = 10; // 2192 1728 1232 976 |
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54 | |||
55 | /** |
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56 | * @var array |
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57 | */ |
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58 | protected $matrix = []; |
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59 | |||
60 | /** |
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61 | * @var int |
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62 | */ |
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63 | protected $pixelCount = 0; |
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64 | |||
65 | /** |
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66 | * @var int |
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67 | */ |
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68 | protected $typeNumber; |
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69 | |||
70 | /** |
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71 | * @var int |
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72 | */ |
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73 | protected $errorCorrectLevel; |
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74 | |||
75 | /** |
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76 | * @var int |
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77 | */ |
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78 | protected $lostPoint; |
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79 | |||
80 | /** |
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81 | * @var int |
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82 | */ |
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83 | protected $darkCount; |
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84 | |||
85 | /** |
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86 | * @var float |
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87 | */ |
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88 | protected $minLostPoint; |
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89 | |||
90 | /** |
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91 | * @var int |
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92 | */ |
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93 | protected $maskPattern; |
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94 | |||
95 | /** |
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96 | * @var \chillerlan\QRCode\BitBuffer |
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97 | */ |
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98 | protected $bitBuffer; |
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99 | |||
100 | /** |
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101 | * @var \chillerlan\QRCode\Data\QRDataInterface |
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102 | */ |
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103 | protected $qrDataInterface; |
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104 | |||
105 | /** |
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106 | * @var \chillerlan\QRCode\Output\QROutputInterface |
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107 | */ |
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108 | protected $qrOutputInterface; |
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109 | |||
110 | /** |
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111 | * QRCode constructor. |
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112 | * |
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113 | * @param string $data |
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114 | * @param \chillerlan\QRCode\Output\QROutputInterface $output |
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115 | * @param \chillerlan\QRCode\QROptions|null $options |
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116 | */ |
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117 | public function __construct($data, QROutputInterface $output, QROptions $options = null){ |
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118 | $this->qrOutputInterface = $output; |
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119 | $this->bitBuffer = new BitBuffer; |
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120 | $this->setData($data, $options); |
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121 | } |
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122 | |||
123 | /** |
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124 | * @param string $data |
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125 | * @param \chillerlan\QRCode\QROptions|null $options |
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126 | * |
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127 | * @return \chillerlan\QRCode\QRCode |
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128 | * @throws \chillerlan\QRCode\QRCodeException |
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129 | */ |
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130 | public function setData(string $data, QROptions $options = null):QRCode { |
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131 | $data = trim($data); |
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132 | |||
133 | if(empty($data)){ |
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134 | throw new QRCodeException('No data given.'); |
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135 | } |
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136 | |||
137 | if(!$options instanceof QROptions){ |
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138 | $options = new QROptions; |
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139 | } |
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140 | |||
141 | if(!in_array($options->errorCorrectLevel, QRConst::RSBLOCK, true)){ |
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142 | throw new QRCodeException('Invalid error correct level: '.$options->errorCorrectLevel); |
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143 | } |
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144 | |||
145 | $this->errorCorrectLevel = $options->errorCorrectLevel; |
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146 | |||
147 | switch(true){ |
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148 | case Util::isAlphaNum($data): |
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149 | $mode = Util::isNumber($data) ? QRConst::MODE_NUMBER : QRConst::MODE_ALPHANUM; |
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150 | break; |
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151 | case Util::isKanji($data): |
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152 | $mode = QRConst::MODE_KANJI; |
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153 | break; |
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154 | default: |
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155 | $mode = QRConst::MODE_BYTE; |
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156 | break; |
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157 | } |
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158 | |||
159 | // see, Scrunitizer, it is concrete! :P |
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160 | $qrDataInterface = [ |
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161 | QRConst::MODE_ALPHANUM => AlphaNum::class, |
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162 | QRConst::MODE_BYTE => Byte::class, |
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163 | QRConst::MODE_KANJI => Kanji::class, |
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164 | QRConst::MODE_NUMBER => Number::class, |
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165 | ][$mode]; |
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166 | |||
167 | $this->qrDataInterface = new $qrDataInterface($data); |
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168 | $this->typeNumber = $options->typeNumber; |
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169 | |||
170 | if(!is_int($this->typeNumber) || $this->typeNumber < 1 || $this->typeNumber > 10){ |
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171 | $this->typeNumber = $this->getTypeNumber($mode); |
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172 | } |
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173 | |||
174 | return $this; |
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175 | } |
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176 | |||
177 | /** |
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178 | * @param int $mode |
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179 | * |
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180 | * @return int |
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181 | * @throws \chillerlan\QRCode\QRCodeException |
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182 | */ |
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183 | protected function getTypeNumber(int $mode):int { |
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184 | $length = $this->qrDataInterface->dataLength; |
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185 | |||
186 | if($this->qrDataInterface->mode === QRConst::MODE_KANJI){ |
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187 | $length = floor($length / 2); |
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188 | } |
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189 | |||
190 | foreach(range(1, 10) as $type){ |
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191 | if($length <= Util::getMaxLength($type, $mode, $this->errorCorrectLevel)){ |
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192 | return $type; |
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193 | } |
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194 | } |
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195 | |||
196 | throw new QRCodeException('Unable to determine type number.'); // @codeCoverageIgnore |
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197 | } |
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198 | |||
199 | /** |
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200 | * @return mixed |
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201 | */ |
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202 | public function output(){ |
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203 | $this->qrOutputInterface->setMatrix($this->getRawData()); |
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204 | |||
205 | return $this->qrOutputInterface->dump(); |
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206 | } |
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207 | |||
208 | /** |
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209 | * @return array |
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210 | */ |
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211 | public function getRawData():array { |
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223 | |||
224 | /** |
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225 | * @param array $range |
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226 | * |
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227 | * @return void |
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228 | */ |
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229 | protected function testLevel1(array $range){ |
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260 | |||
261 | /** |
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262 | * @param array $range |
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263 | * |
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264 | * @return void |
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265 | */ |
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266 | protected function testLevel2(array $range){ |
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289 | |||
290 | /** |
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291 | * @param array $range1 |
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292 | * @param array $range2 |
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293 | * |
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294 | * @return void |
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295 | */ |
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296 | protected function testLevel3(array $range1, array $range2){ |
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335 | |||
336 | /** |
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337 | * @param array $range |
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338 | * |
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339 | * @return void |
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340 | */ |
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341 | protected function testLevel4(array $range){ |
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352 | |||
353 | /** |
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354 | * @param int $pattern |
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355 | * |
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356 | * @return void |
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357 | */ |
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358 | protected function testPattern(int $pattern){ |
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378 | |||
379 | /** |
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380 | * @param bool $test |
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381 | * |
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382 | * @return void |
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383 | */ |
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384 | protected function setTypeNumber(bool $test){ |
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395 | |||
396 | /** |
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397 | * @param bool $test |
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398 | * @param int $pattern |
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399 | * |
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400 | * @return void |
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401 | */ |
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402 | protected function setTypeInfo(bool $test, int $pattern){ |
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427 | |||
428 | /** |
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429 | * @return void |
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430 | * @throws \chillerlan\QRCode\QRCodeException |
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431 | */ |
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432 | protected function createData(){ |
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477 | |||
478 | /** |
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479 | * @return array |
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480 | * @throws \chillerlan\QRCode\QRCodeException |
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481 | */ |
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482 | protected function createBytes():array { |
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546 | |||
547 | /** |
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548 | * @param int $pattern |
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549 | * |
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550 | * @return void |
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551 | * @throws \chillerlan\QRCode\QRCodeException |
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552 | */ |
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553 | protected function mapData(int $pattern){ |
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615 | |||
616 | /** |
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617 | * @return void |
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618 | */ |
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619 | protected function setupPositionProbePattern(){ |
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642 | |||
643 | /** |
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644 | * @return void |
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645 | */ |
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646 | protected function setupPositionAdjustPattern(){ |
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667 | |||
668 | /** |
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669 | * @return void |
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670 | * @throws \chillerlan\QRCode\QRCodeException |
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671 | */ |
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672 | protected function setPattern(){ |
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686 | |||
687 | /** |
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688 | * @param bool $test |
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689 | * @param int $maskPattern |
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690 | * |
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691 | * @throws \chillerlan\QRCode\QRCodeException |
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692 | */ |
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693 | protected function getMatrix(bool $test, int $maskPattern){ |
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704 | |||
705 | } |
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706 |
If you access a property on an interface, you most likely code against a concrete implementation of the interface.
Available Fixes
Adding an additional type check:
Changing the type hint: