Extension\StringTest::testSubstr PHP Method

    public function testSubstr()
    {
        $t = new \Test\Strings();
        $this->assertSame($t->testSubstr('abcdef', 1, 3), 'bcd');
        $this->assertSame($t->testSubstr('abcdef', 0, 4), 'abcd');
        $this->assertSame($t->testSubstr('abcdef', 0, 8), 'abcdef');
        $this->assertSame($t->testSubstr('abcdef', -1, 1), 'f');
        $this->assertSame($t->testSubstr('abcdef', -3, -1), 'de');
        $this->assertSame($t->testSubstr('abcdef', 2, -1), 'cde');
        $this->assertSame($t->testSubstr2('abcdef', -1), 'f');
        $this->assertSame($t->testSubstr2('abcdef', -2), 'ef');
        $this->assertSame($t->testSubstr2('abcdef', 2), 'cdef');
        $this->assertSame($t->testSubstr3('abcdef'), 'f');
        $this->assertSame($t->testSubstr4('abcdef'), 'abcde');
    }