调试 package::function() 虽然使用了惰性求值 [英] Debugging package::function() although lazy evaluation is used

问题描述

如果由于惰性求值导致包未知，我如何在 R 中高效调试.我想保留基本的 browser() 功能，因为它很好用 - 即使使用 testthat 包.如以下帖子中所述，--with-keep.source 在项目选项 => 构建工具"中为我的项目设置.

How can I debug efficiently in R if packages are unknown due to lazy evaluation. I would like to keep the basic browser() functionality as it works great - even with the testthat package. As explained in the following post, --with-keep.source is set for my project in "project options => Build Tools".

要重现该行为，请创建一个包含

To reproduce the behavior, create a package TestDebug containing

myfun <- function(a,b) {return(a+b)}

和脚本 example.R

{
browser()
TestDebug::myfun(1,2)
}

编辑:TestDebug::myfun(1,2)调用otherpackage::myfun2(1,2)的情况应该是也覆盖.我认为这种情况应该出现在每个真实"的包裹中?

Edit: The situation where TestDebug::myfun(1,2) calls otherpackage::myfun2(1,2) should be also covered. I think the situation should occur in every "real" package?

推荐答案

以下对我有用.

我有我的包 TestDebug 和我的函数

I have my package TestDebug with my function

myfun <- function(a,b) {return(a+b)}

如果我运行脚本

debug(TestDebug::myfun)
TestDebug::myfun(1,2)

调试器直接进入 TestDebug::myfun() 的源代码，而不是像放置 browser() 时那样进入 :: 函数 在调用 TestDebug::myfun(1,2) 之前.

The debugger steps right into the source of TestDebug::myfun() not into the :: function as it does when you place a browser() before the call to TestDebug::myfun(1,2).

正如您在问题中提到的:在现实生活中，TestDebug::myfun(1,2) 经常调用 otherpackage::myfun2(1,2).如果您尝试进入 otherpackage::myfun2(1,2)，您将再次进入 :: 函数.

As you mention in your question: in real-life situations TestDebug::myfun(1,2) often calls otherpackage::myfun2(1,2). If you try to step into otherpackage::myfun2(1,2) you will end up inside the :: function again.

为了防止这种情况，我将在其他函数中调用的这个函数即时添加到 debug 索引中:

To prevent this I add this functions called inside other functions to the debug index on the fly:

只要您在 TestDebug::myfun() 内的线路上，其中 otherpackage::myfun2(1,2) 被称为我运行 debug(otherpackage::myfun2(1,2)) 在控制台中.之后，我可以毫无问题地进入 otherpackage::myfun2(1,2) 并最终进入 otherpackage::myfun2(1,2) 的源代码.(..并且不在 :: 的源代码中)

As soon as you are on the line inside TestDebug::myfun() where otherpackage::myfun2(1,2) is called I run debug(otherpackage::myfun2(1,2)) in the console. After that I can step into otherpackage::myfun2(1,2) without problems and end up in the source code of otherpackage::myfun2(1,2). (..and not in the source code of ::)

在确定您的问题不在 otherpackage::myfun2(1,2) 内之后，不要忘记调用 undebug(otherpackage::myfun2(1,2))) 以防止调试器在下次调用时跳转到 otherpackage::myfun2(1,2).

Don't forget to call undebug(otherpackage::myfun2(1,2)) after you're sure that your problem is not inside otherpackage::myfun2(1,2) to prevent the debugger to jump into otherpackage::myfun2(1,2) the next time it is called.

如果你愿意，你也可以使用 debugonce(otherpackage::myfun(1,2))(而不是 debug(..))来只调试一个函数一次.

If you prefer you can also use debugonce(otherpackage::myfun(1,2)) (instead of debug(..)) to only debug a function once.

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