【CTS】几个serialno失败项

【问题结论】
AuthorBlog：秋城https://www.cnblogs.com/houser0323/
ro.serialno的问题，只可以‘数字与大小写字母’改为字母数字组合，测试全部pass
【问题描述】
CTS三条失败项

run cts -m CtsTelephonyTestCases -t android.telephony.cts.TelephonyManagerTest#testGetDeviceId
run cts -m CtsTelephonyTestCases -t android.telephony.cts.TelephonyManagerTest#testGetDeviceIdForSlot
run cts -m CtsUsbTests -t com.android.cts.usb.TestUsbTest#testUsbSerialReadOnDeviceMatches

问题日志：

06-10 15:29:58 I/ConsoleReporter: [1/1 armeabi-v7a CtsUsbTests xxx_xxx_111_00000111] com.android.cts.usb.TestUsbTest#testUsbSerialReadOnDeviceMatches fail: junit.framework.ComparisonFailure: usb serial != adb serial expected:<[]> but was:<[xxx_xxx_111_00000111]>
    at junit.framework.Assert.assertEquals(Assert.java:100)
    at junit.framework.TestCase.assertEquals(TestCase.java:261)
    at com.android.cts.usb.TestUsbTest.testUsbSerialReadOnDeviceMatches(TestUsbTest.java:162)

【问题分析】

• 源码追溯

cts / master / . / hostsidetests / usb / src / com / android / cts / usb / TestUsbTest.java
/**
     * Check if adb serial number, USB serial number, ro.serialno, and android.os.Build.SERIAL
     * all matches and meets the format requirement [a-zA-Z0-9]{6,20}
     */
public void testInstantAppsCannotReadSerial() throws Exception {
......
        CommandResult result = RunUtil.getDefault().runTimedCmd(5000, "lsusb", "-v");//这一句是在linux测试机执行shell命令"lsusb -v"
......
        String lsusbOutput = result.getStdout();
        Pattern pattern = Pattern.compile("^\s+iSerial\s+\d+\s+([a-zA-Z0-9]{6,20})",Pattern.MULTILINE);//在上句命令的返回值中匹配，看serilnumber是不是合法即“只能由字母数字组成，且6≤lenth≤20”
        Matcher matcher = pattern.matcher(lsusbOutput);
        String usbSerial = "";
        while (matcher.find()) {
            String currentSerial = matcher.group(1).toLowerCase();
            if (adbSerial.compareTo(currentSerial) == 0) {
                usbSerial = currentSerial;
                break;
            }
        }
        assertEquals("usb serial != adb serial" , usbSerial, adbSerial);//由于我们的serialno是带下划线了，所以匹配为空，就抛异常了

• 实验
  在理清源码测试逻辑后，我们将SN配置项修改为“无下划线”的字母数字组合
  实验结果：三条均pass