i would like to change the way SBT for Scala presents informations. Any ideas for modification are wellcome but I am most interested in few thing.
How could be done this?
Remowe parts of information that does not interest you
Color certain piece of information for example test errors in red
Show full error stack trace, asserted object values, place where are differences in compared strings ect
Try to set the log level to info by typing info
Related
I was wondering if there is a way to get a 'simplified' version of the exception stacktrace.
one that does not contain the trace of functions that are sourced in outside site-packages.
kind of like Justmycode. but for python with pycharm..
I have tried looking around but haven't found anything yet,
i'm aware that I can take the Stacktrace and filter out rows that are from outside sources,
but I really thought there would already be a solution for it?
Thanks in advance!
The tbvaccine Python package shows relevant lines highlighted, which is like a visual filter of irrelevant lines.
The package doesn't seem to be under active development btw.
I'm frustrated by unintelligible stacktraces when my Scala.js code throws an exception. I thought I had a solution using a Javascript library (see Getting a scala stacktrace) but it breaks too often.
How do you extract meaning (where the program broke; how it got there -- in terms of the Scala code) from a stacktrace like the following. Or am I doing something wrong to even get an untranslated stacktrace?
Take a look at this code I wrote a while back in my youi framework: https://github.com/outr/youi/tree/e66dc36a12780fa8941152d07de9c3a52d28fc10/app/js/src/main/scala/io/youi/app/sourceMap
It is used to reverse JS stack traces to Scala stack traces. In youi I send the errors to the server so I can monitor browser errors that occur with the complete traceback.
Brief Overview
source-map.js
You need source-map.js to parse the js.map file that Scala.js
generated when it compiled your code. See:
https://github.com/mozilla/source-map
Load the js.map file via Ajax
The SourceMapConsumer needs a js.Object (JSON) of the js.map file. See https://github.com/outr/youi/blob/e66dc36a12780fa8941152d07de9c3a52d28fc10/app/js/src/main/scala/io/youi/app/sourceMap/ErrorTrace.scala#L58 for an example of loading via youi's Ajax features.
Process the Throwable
The trace represents line and columns in the JS file and you can pass
that information to SourceMapConsumer to get the original Scala line
numbers back (see SourceMapConsumer.originalPositionFor). See
ErrorTrace.toCause
(https://github.com/outr/youi/blob/e66dc36a12780fa8941152d07de9c3a52d28fc10/app/js/src/main/scala/io/youi/app/sourceMap/ErrorTrace.scala#L98)
for an example iterating over the Throwable's trace elements.
Handling Errors
Now that you have the capacity to process JavaScript errors and
convert them back to Scala traces, you need to actually receive the
errors. If you want to globally handle uncaught errors set a function
to window.onerror to capture errors. As of this writing, the
function signature in Scala.js isn't ideal for handling all
information, so in youi I use js.Dynamic to set it to what I need
(see:
https://github.com/outr/youi/blob/e66dc36a12780fa8941152d07de9c3a52d28fc10/app/js/src/main/scala/io/youi/app/ClientApplication.scala#L35).
Also, notice that in ErrorTrace it supports multiple incoming types
of errors (ErrorEvent, Throwable, and a more generic scenario).
This is because in JavaScript the errors come in different ways based
on what's happening. This is a fairly complex topic, and why I
created this functionality in youi to simplify things.
Not nearly as brief an overview as I would have liked, but this isn't a simple problem to solve. The source-map GitHub project (https://github.com/mozilla/source-map) has decent documentation and is what I used originally to write my solution (with some added trial and error). If the information I've provided is incomplete I'd recommend reading more there as it should provide the majority of information, and probably better explained.
I'd like to be able to turn off a particular compiler warning, but only for a single file in my project. Is this possible?
The context is that I have a single source file that makes calls to an external macro library that produces adapted-arg warnings. I found that I can eliminate these warnings by changing my build.sbt file:
scalacOptions ++= Seq("-Xlint:-adapted-args,_" /*, ... */)
However, this turns off the warning globally, and I only want it off for the single file that raises them.
I haven't had any luck searching for any of the following possible solutions I thought might exist:
Specifying separate compilation options for different files in my project in my build.sbt file
Providing some pragma-like comment in my source file to change the warnings generated by the compiler, similar to the special scalastyle:on/off comments recognized by Scalastyle
Some annotation for smaller regions of code, like #unchecked
So, is there any way to have different linting options in effect for different files, or even for limited regions of code?
The expectation was that folks would write a custom Reporter that would filter out undesirable warnings.
It's easy to write one that filters by file name, perhaps given a whitelist.
The error/warn API supplies the textual Position. It would also be easy to parse the position.lineContent for a magic comment token like IGNORE or SUPPRESS, which is not as convenient as a SuppressWarnings annotation but is easy to implement.
The compiler asks the reporter if there were errors.
The custom reporter is specified with -Xreporter myclass, or it wouldn't surprise me if someone has written an sbt plugin.
I am using STS 3.4 and working on a web application based on Grails framework.
When i try to use System.err.println in groovy classes it does not print anything on standard eclipse console(STS console).
Actually there are times when in print things but that is like 1 in 10, I couldn't understand this random behavior.
I am using some library that uses System.err.println for debugging purposes but i could not get any debugging info. All i need to know is where and how to get System.err.println output?
Please help me, Thanks in advance
If it is a random behaviour, it may be not-flush-ed buffered stream. Especially, that can happen when output comes from different thread.
As a solution, you can hook in into System.err dispatching (it's a stream, that you can set from outside), and overload functions, to get desired output anywhere you want. Or simply force flush it. But be careful, as it may lead to performance problems.
Consider using logging instead for more standard and configurable output. This should help you to set it up: http://groovy.codehaus.org/Logging
I'm not much of an Eclipse guru, so please forgive my clumsiness.
In Eclipse, when I call Assert.assertEquals(obj1,obj2) and that fails, how do I get the IDE to show me obj1 and obj2?
I'm using JExample, but I guess that shouldn't make a difference.
Edit: Here's what I see:
(source: yfrog.com)
.
Comparison with failure trace is not a easy task when your object is a little bit complex.
Comparison with debugger is useful if you have not redefined toString(). It remains still very tedious as solution because you should inspect with your eyes each objects from both sides.
Junit Eclipse plugin offers a option when there is a failure : "Compare actual With Expected TestResult". The view is close enough to classic content comparison tools :
Problem is that it is avaiable only when you writeassertEquals() with String objects (in the screenshot, we can see that the option in the corner is not proposed with no String class) :
You may use toString() on your object in assertion but it's not a good solution :
firstly, you correlate toString() with equals(Object)... modification of one must entail modification of the other.
secondly, the semantic is not any longer respected. toString() should return a useful method to debug the state of one object, not to identify an object in the Java semantic (equals(Object)).
According to me, I think that the JUnit Eclipse plugin misses a feature.
When comparison fails, even when we compare not String objects, it should offer a comparison of the two objects which rely on their toString() method.
It could offer a minimal visual way of comparing two unequals objects.
Of course, as equals(Object) is not necessarily correlated to toString(), highlighted differences should be studied with our eyes but it would be already a very good basis and anyway, it is much better than no comparison tool.
If the information in the JUnit view is not enough for you, you can always set a exception breakpoint on, for example, java.lang.AssertionError. When running the test, the debugger will stop immediately before the exception is actually being thrown.
Assert.assertEquals() will put the toString() representation of the expected and actual object in the message of the AssertionFailedError it throws, and eclipse will display that in the "failure trace" part of the JUnit view:
(source: ibm.com)
If you have complex objects you want to inspect, you'll have to use the debugger and put a breakpoint inside Assert.assertEquals()
What are you seeing?
When you do assertTrue() and it fails, you see a null.
But when you do assertEquals, it is supposed to show you what it expected and what it actually got.
If you are using JUnit, mke sure you are looking at the JUnit view and moving the mouse to the failed test.
FEST Assert will display comparison dialog in case of assertion failure even when objects you compare are not strings. I explained it in more detail on my blog.
If what you are comparing is a String then you can double click stack element and it will popup a dialog showing the diff in eclipse.
This only works with Strings though. For the general case the only way to see the real reason is to install a breakpoint and step into it.