我试图在Kotlin为我的android应用程序做UI测试。由于新系统使用ActivityTestRule，我不能使它工作:它编译正确，在运行时，我得到:

java.lang.Exception: The @Rule 'mActivityRule' must be public.
    at org.junit.internal.runners.rules.RuleFieldValidator.addError(RuleFieldValidator.java:90)
    at org.junit.internal.runners.rules.RuleFieldValidator.validatePublic(RuleFieldValidator.java:67)
    at org.junit.internal.runners.rules.RuleFieldValidator.validateField(RuleFieldValidator.java:55)
    at org.junit.internal.runners.rules.RuleFieldValidator.validate(RuleFieldValidator.java:50)
    at org.junit.runners.BlockJUnit4ClassRunner.validateFields(BlockJUnit4ClassRunner.java:170)
    at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:103)
    at org.junit.runners.ParentRunner.validate(ParentRunner.java:344)
    at org.junit.runners.ParentRunner.<init>(ParentRunner.java:74)
    at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:55)
    at android.support.test.internal.runner.junit4.AndroidJUnit4ClassRunner.<init>(AndroidJUnit4ClassRunner.java:38)
    at android.support.test.runner.AndroidJUnit4.<init>(AndroidJUnit4.java:36)
    at java.lang.reflect.Constructor.constructNative(Native Method)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
    at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.buildAndroidRunner(AndroidAnnotatedBuilder.java:57)
    at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.runnerForClass(AndroidAnnotatedBuilder.java:45)
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
    at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29)
    at org.junit.runner.Computer.getRunner(Computer.java:38)
    at org.junit.runner.Computer$1.runnerForClass(Computer.java:29)
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
    at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:98)
    at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:84)
    at org.junit.runners.Suite.<init>(Suite.java:79)
    at org.junit.runner.Computer.getSuite(Computer.java:26)
    at android.support.test.internal.runner.TestRequestBuilder.classes(TestRequestBuilder.java:691)
    at android.support.test.internal.runner.TestRequestBuilder.build(TestRequestBuilder.java:654)
    at android.support.test.runner.AndroidJUnitRunner.buildRequest(AndroidJUnitRunner.java:329)
    at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:226)
    at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1584)

下面是我如何声明mActivityRule:

RunWith(javaClass<AndroidJUnit4>())
LargeTest
public class RadisTest {

    Rule
    public val mActivityRule: ActivityTestRule<MainActivity> = ActivityTestRule(javaClass<MainActivity>())

   ...
}

它已经是公共的:/

Subversion、Git、Mercurial和其他版本支持三方合并(结合我的、他们的和“基础”版本)，并支持图形工具来解决冲突。

你用什么工具?Windows, Mac OS X, Linux，免费或商业，你能想到的。

下面是一些我用过或听说过的，只是为了开始对话:

KDiff3 DiffMerge P4Merge 融合 Beyond Compare Pro。

(我承认这有点像最佳差异工具，但它的不同之处在于我明确地专注于三方合并工具;例如，WinMerge就不在此列。)

为什么这段代码给输出c++吸?它背后的概念是什么?

#include <stdio.h>

double m[] = {7709179928849219.0, 771};

int main() {
    m[1]--?m[0]*=2,main():printf((char*)m);    
}

在这里测试。

我有两个YAML文件，“A”和“B”，我希望将A的内容插入到B中，要么拼接到现有的数据结构中，就像数组一样，要么作为元素的子元素，就像某个散列键的值一样。

这可能吗?怎么做?如果不是，是否有指向规范引用的指针?

一段时间以来，我一直在我的个人项目中使用subversion。

我听到越来越多关于Git、Mercurial和DVCS的好消息。

我想尝试一下DVCS，但我对这两种选择都不太熟悉。

Mercurial和Git之间有什么区别?

注意:我并不是要找出哪一个是“最好的”，或者我应该从哪一个开始。我主要寻找它们相似和不同的关键领域，因为我想知道它们在实现和理念方面有何不同。

什么是有效的方法来取代一个字符的所有出现与另一个字符在std::字符串?

我已经在Windows上使用git有一段时间了(使用msysGit)，我喜欢分布式源代码控制的想法。就在最近，我一直在关注Mercurial (hg)，它看起来很有趣。然而，我无法理解hg和git之间的区别。

有人把git和hg放在一起比较吗?我很想知道hg和git有什么不同，而不需要加入粉丝的讨论。

我能够通过HTTPS认证克隆此回购的副本。我已经提交了一些内容，希望将其推回到GitHub服务器。在Windows 7 x64上使用Cygwin。

C:\cygwin\home\XPherior\Code\lunch_call>git push
Password:
error: The requested URL returned error: 403 while accessing https://MichaelDrog
alis@github.com/derekerdmann/lunch_call.git/info/refs

fatal: HTTP request failed

还可以设置为详细模式。我还是很困惑。

C:\cygwin\home\XPherior\Code\lunch_call>set GIT_CURL_VERBOSE=1

C:\cygwin\home\XPherior\Code\lunch_call>git push
Password:
* Couldn't find host github.com in the _netrc file; using defaults
* About to connect() to github.com port 443 (#0)
*   Trying 207.97.227.239... * 0x23cb740 is at send pipe head!
* Connected to github.com (207.97.227.239) port 443 (#0)
* successfully set certificate verify locations:
*   CAfile: C:\Program Files (x86)\Git/bin/curl-ca-bundle.crt
  CApath: none
* SSL connection using AES256-SHA
* Server certificate:
*        subject: 2.5.4.15=Private Organization; 1.3.6.1.4.1.311.60.2.1.3=US; 1.
3.6.1.4.1.311.60.2.1.2=California; serialNumber=C3268102; C=US; ST=California; L
=San Francisco; O=GitHub, Inc.; CN=github.com
*        start date: 2011-05-27 00:00:00 GMT
*        expire date: 2013-07-29 12:00:00 GMT
*        subjectAltName: github.com matched
*        issuer: C=US; O=DigiCert Inc; OU=www.digicert.com; CN=DigiCert High Ass
urance EV CA-1
*        SSL certificate verify ok.
> GET /derekerdmann/lunch_call.git/info/refs?service=git-receive-pack HTTP/1.1
User-Agent: git/1.7.4.3282.g844cb
Host: github.com
Accept: */*
Pragma: no-cache

< HTTP/1.1 401 Authorization Required
< Server: nginx/1.0.4
< Date: Thu, 15 Sep 2011 22:44:41 GMT
< Content-Type: text/plain
< Connection: keep-alive
< Content-Length: 55
< WWW-Authenticate: Basic realm="GitHub"
<
* Ignoring the response-body
* Expire cleared
* Connection #0 to host github.com left intact
* Issue another request to this URL: 'https://MichaelDrogalis@github.com/dereker
dmann/lunch_call.git/info/refs?service=git-receive-pack'
* Couldn't find host github.com in the _netrc file; using defaults
* Re-using existing connection! (#0) with host github.com
* Connected to github.com (207.97.227.239) port 443 (#0)
* 0x23cb740 is at send pipe head!
* Server auth using Basic with user 'MichaelDrogalis'
> GET /derekerdmann/lunch_call.git/info/refs?service=git-receive-pack HTTP/1.1
Authorization: Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
User-Agent: git/1.7.4.3282.g844cb
Host: github.com
Accept: */*
Pragma: no-cache

< HTTP/1.1 401 Authorization Required
< Server: nginx/1.0.4
< Date: Thu, 15 Sep 2011 22:44:41 GMT
< Content-Type: text/plain
< Connection: keep-alive
< Content-Length: 55
* Authentication problem. Ignoring this.
< WWW-Authenticate: Basic realm="GitHub"
* The requested URL returned error: 401
* Closing connection #0
* Couldn't find host github.com in the _netrc file; using defaults
* About to connect() to github.com port 443 (#0)
*   Trying 207.97.227.239... * 0x23cb740 is at send pipe head!
* Connected to github.com (207.97.227.239) port 443 (#0)
* successfully set certificate verify locations:
*   CAfile: C:\Program Files (x86)\Git/bin/curl-ca-bundle.crt
  CApath: none
* SSL re-using session ID
* SSL connection using AES256-SHA
* old SSL session ID is stale, removing
* Server certificate:
*        subject: 2.5.4.15=Private Organization; 1.3.6.1.4.1.311.60.2.1.3=US; 1.
3.6.1.4.1.311.60.2.1.2=California; serialNumber=C3268102; C=US; ST=California; L
=San Francisco; O=GitHub, Inc.; CN=github.com
*        start date: 2011-05-27 00:00:00 GMT
*        expire date: 2013-07-29 12:00:00 GMT
*        subjectAltName: github.com matched
*        issuer: C=US; O=DigiCert Inc; OU=www.digicert.com; CN=DigiCert High Ass
urance EV CA-1
*        SSL certificate verify ok.
* Server auth using Basic with user 'MichaelDrogalis'
> GET /derekerdmann/lunch_call.git/info/refs HTTP/1.1
Authorization: Basic xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
User-Agent: git/1.7.4.3282.g844cb
Host: github.com
Accept: */*
Pragma: no-cache

* The requested URL returned error: 403
* Expire cleared
* Closing connection #0
error: The requested URL returned error: 403 while accessing https://MichaelDrog
alis@github.com/derekerdmann/lunch_call.git/info/refs

fatal: HTTP request failed

以下是我的git和curl版本：

C:\Users\XPherior>git --version
git version 1.7.4.msysgit.0

C:\Users\XPherior>curl --version
curl 7.21.7 (amd64-pc-win32) libcurl/7.21.7 OpenSSL/0.9.8r zlib/1.2.5
Protocols: dict file ftp ftps gopher http https imap imaps ldap pop3 pop3s rtsp
smtp smtps telnet tftp
Features: AsynchDNS GSS-Negotiate Largefile NTLM SSL SSPI libz

这个C程序是如何工作的?

main(_){_^448&&main(-~_);putchar(--_%64?32|-~7[__TIME__-_/8%8][">'txiZ^(~z?"-48]>>";;;====~$::199"[_*2&8|_/64]/(_&2?1:8)%8&1:10);}

它按原样编译(在gcc 4.6.3上进行了测试)。它在编译时打印时间。在我的系统中:

    !!  !!!!!!              !!  !!!!!!              !!  !!!!!! 
    !!  !!  !!              !!      !!              !!  !!  !! 
    !!  !!  !!              !!      !!              !!  !!  !! 
    !!  !!!!!!    !!        !!      !!    !!        !!  !!!!!! 
    !!      !!              !!      !!              !!  !!  !! 
    !!      !!              !!      !!              !!  !!  !! 
    !!  !!!!!!              !!      !!              !!  !!!!!!

来源:sykes2 -一行中的时钟，sykes2作者提示

一些提示:默认情况下没有编译警告。使用-Wall编译，会发出以下警告:

sykes2.c:1:1: warning: return type defaults to ‘int’ [-Wreturn-type]
sykes2.c: In function ‘main’:
sykes2.c:1:14: warning: value computed is not used [-Wunused-value]
sykes2.c:1:1: warning: implicit declaration of function ‘putchar’ [-Wimplicit-function-declaration]
sykes2.c:1:1: warning: suggest parentheses around arithmetic in operand of ‘|’ [-Wparentheses]
sykes2.c:1:1: warning: suggest parentheses around arithmetic in operand of ‘|’ [-Wparentheses]
sykes2.c:1:1: warning: control reaches end of non-void function [-Wreturn-type]

我刚刚在我的新项目的根上做了一个git初始化。

然后我创建了一个.gitignore文件。

现在，当我输入git status时，.gitignore文件出现在未跟踪文件列表中。为什么呢?