Complex classes like SubTest 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 SubTest, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 17 | class SubTest extends AbstractTestCase  | 
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| 18 | { | 
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| 19 | public function testSubYearsPositive()  | 
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| 23 | |||
| 24 | public function testSubYearsZero()  | 
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| 28 | |||
| 29 | public function testSubYearsNegative()  | 
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| 33 | |||
| 34 | public function testSubYear()  | 
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| 38 | |||
| 39 | public function testSubMonthsPositive()  | 
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| 43 | |||
| 44 | public function testSubMonthsZero()  | 
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| 48 | |||
| 49 | public function testSubMonthsNegative()  | 
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| 53 | |||
| 54 | public function testSubMonth()  | 
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| 58 | |||
| 59 | public function testSubDaysPositive()  | 
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| 63 | |||
| 64 | public function testSubDaysZero()  | 
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| 68 | |||
| 69 | public function testSubDaysNegative()  | 
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| 73 | |||
| 74 | public function testSubDay()  | 
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| 78 | |||
| 79 | public function testSubWeekdaysPositive()  | 
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| 83 | |||
| 84 | public function testSubWeekdaysZero()  | 
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| 88 | |||
| 89 | public function testSubWeekdaysNegative()  | 
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| 93 | |||
| 94 | public function testSubWeekday()  | 
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| 98 | |||
| 99 | public function testSubWeekdayDuringWeekend()  | 
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| 103 | |||
| 104 | public function testSubWeeksPositive()  | 
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| 108 | |||
| 109 | public function testSubWeeksZero()  | 
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| 113 | |||
| 114 | public function testSubWeeksNegative()  | 
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| 118 | |||
| 119 | public function testSubWeek()  | 
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| 123 | |||
| 124 | public function testSubHoursPositive()  | 
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| 128 | |||
| 129 | public function testSubHoursZero()  | 
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| 133 | |||
| 134 | public function testSubHoursNegative()  | 
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| 138 | |||
| 139 | public function testSubHour()  | 
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| 143 | |||
| 144 | public function testSubMinutesPositive()  | 
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| 148 | |||
| 149 | public function testSubMinutesZero()  | 
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| 153 | |||
| 154 | public function testSubMinutesNegative()  | 
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| 158 | |||
| 159 | public function testSubMinute()  | 
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| 163 | |||
| 164 | public function testSubSecondsPositive()  | 
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| 168 | |||
| 169 | public function testSubSecondsZero()  | 
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| 173 | |||
| 174 | public function testSubSecondsNegative()  | 
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| 178 | |||
| 179 | public function testSubSecond()  | 
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| 183 | |||
| 184 | /***** Test non plural methods with non default args *****/  | 
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| 185 | |||
| 186 | public function testSubYearPassingArg()  | 
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| 190 | |||
| 191 | public function testSubMonthPassingArg()  | 
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| 195 | |||
| 196 | public function testSubMonthNoOverflowPassingArg()  | 
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| 202 | |||
| 203 | public function testSubDayPassingArg()  | 
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| 207 | |||
| 208 | public function testSubHourPassingArg()  | 
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| 212 | |||
| 213 | public function testSubMinutePassingArg()  | 
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| 217 | |||
| 218 | public function testSubSecondPassingArg()  | 
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| 222 | }  | 
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| 223 |