2023/05/17(水) Qiita Conference 2023
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ΞοϓσʔτΛॏͶΔߨԋͷ݄൛Ͱ͢ʢ࿈ࡌୈճ·ͰऩʣIUUQTTQFBLFSEFDLDPNUXBEBίϥϜ࿈ࡌͷୈճ·Ͱऩ͍ͯ͠·͢
ߨԋͷจࣈى͜͠ࠓޙެ։༧ఆͰ͢ެ։͞ΕͨΒTQFBLFSEFDLͷಉҰ63-ͰࢿྉΛΞοϓσʔτ͠·͢
t-wadat_wadatwada📷🙆 📹🙅🙆ࣗݾհ#QiitaConference
ٕज़ॻͷग़൛ʹؔΘ͍ͬͯ·͢
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/*** @test* @group learning*/public function DateTimeのaddは自身の状態を変更しつつ自身を返す(): void{$halloween = new \DateTime('2021-10-31');$oneYear = \DateInterval::createFromDateString('1 year');$halloween2022 = $halloween->add($oneYear);$this->assertSame($halloween, $halloween2022);$this->assertEquals('2022-10-31', $halloween->format('Y-m-d'));$this->assertEquals('2022-10-31', $halloween2022->format('Y-m-d'));}/*** @test* @group learning*/public function DateTimeImmutableのaddは自身の状態を変更せず新しい状態を伴う新しいインスタンスを返す(): void{$halloween = new \DateTimeImmutable('2021-10-31');$oneYear = \DateInterval::createFromDateString('1 year');$halloween2022 = $halloween->add($oneYear);$this->assertNotSame($halloween, $halloween2022);$this->assertEquals('2021-10-31', $halloween->format('Y-m-d'));$this->assertEquals('2022-10-31', $halloween2022->format('Y-m-d'));}%BUF5JNFͱ%BUF5JNF*NNVUBCMFͷҧ͍Λֶशςετʹ͢Δֶशςετʢֶͼ͕తͷςετʣΛݟ͚ΔͨΊʹMFBSOJOHλάΛ͚͍ͭͯ·ֶ͕͢͜͜ͼֶ͕͜͜ͼ
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/*** @test* @group learning*/public function 同じ時刻を指している場合はタイムゾーンが異なっても等価とみなされる(): void{$utc = new DateTimeImmutable('2021-12-24T15:00:00', new DateTimeZone('UTC'));$jst = new DateTimeImmutable('2021-12-25T00:00:00', new DateTimeZone('Asia/Tokyo'));$this->assertTrue($utc == $jst);}ٙΛςετʹ͢Δςετʹฉ͍ͯΈΕ͍͍
ڻ͖Λςετʹ͢Δྫ͑ʜʜ
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/*** @test* @group learning*/public function コンストラクタをもう一度呼ぶと破壊的変更ができてしまう(): void{$dt = new \DateTimeImmutable('2021-12-24');$this->assertSame('2021-12-24', $dt->format('Y-m-d'));$dt->__construct('2022-01-01');$this->assertSame('2022-01-01', $dt->format('Y-m-d'));}ͳΜʜʜͩͱʜʜʂʁ໌ࣔతʹݺͯ͠·͏༨ஊ͜ͷςετίʔυΛ͖͔͚ͬʹQIQTSDʹJTTVFͱͯ͠ใࠂ͞Εɺ͕ٞߦΘΕ·ͨ͠ɻIUUQTHJUIVCDPNQIQQIQTSDJTTVFT༨ஊ͜ͷςετίʔυΛ͖͔͚ͬʹ੩తղੳπʔϧ1)14UBOͱ1TBMNʹػೳఏҊ͕ߦΘΕɺ1)14UBOʹ!NVOP@͞Μ͕࡞ͨ͠QVMMSFRVFTU͕࠾༻͞ΕɺϦϦʔε͞Ε·ͨ͠ɻIUUQTHJUIVCDPNQIQTUBOQIQTUBOTSDQVMM
ֶश༻ςετِཅੑͱِӄੑςεταΠζςετμϒϧςετϐϥϛουࣗಈςετͷαΠζμϯઓུ"HFOEB࿈ࡌ֤ճͷςʔϚ🦁
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