+1 for keeping the tabs vs space for now. When I start working on Flink I was itching to move to spaces indentation since that makes reader consistent. But that was the choice by preference made early on and I think we could keep it and add as exception in Java code style.
Scala, on the other hand is different. We should stick with Scala standard code style and add exceptions as needed. For those don't pay attention, there has been small backlash when Databricks announce it's "Scala coding guide" which not promoting the recommended way of FP use for Scala. I would like to have written agreement on style, meaning stricter style check for Java and Scala. The idea is to reduce heterogeneity of the code for easy to follow and understand. Right now the existing committers have good agreement of code style but like I have said before, the bigger the community the harder to enforce this style (e.g: Hadoop) - Henry On Wed, Mar 18, 2015 at 8:56 AM, Robert Metzger <rmetz...@apache.org> wrote: > I'm against changing the indentation, for the same reasons as Stephan > listed. > > In my opinion, the codebase has grown too large to "just" switch the > indentation or the entire code style (to the google style or whatever). > We have 235870 LOC of Java and 24173 LOC of Scala. > > Therefore, I'm proposing to: > a) Decide on one validation framework (Guava seems to be our favorite > here), change & document it. > b) Decide on one parsing framework, change & document it. > c) Decide on a list of checkstyle rules. > d) Add pull requests for each rule, adding it to the checkstyle > configuration and making the code compliant. > > > Regarding the rules themselves: I have the impression that there is an > unwritten agreement on the code style by the core committers of Flink. > There might be some minor differences nobody cares about .. but all in all > the majority of the code is pretty uniform (at least how I perceive it) > The list of checkstyle rules should basically enforce this "core committers > code style" because it would minimize the number of required changes. Also, > the style has evolved over many years and seems to work well for our needs. > > > > On Wed, Mar 18, 2015 at 4:25 PM, Stephan Ewen <se...@apache.org> wrote: > >> I agree, if we set p a new project, we should use space indentation. >> >> Should we really refactor 300k lines of code? Would be massive. >> >> Also: The history would basically show a single committer for all code. Git >> blame (for error tracing) would become useless. >> >> On Wed, Mar 18, 2015 at 3:49 PM, Alexander Alexandrov < >> alexander.s.alexand...@gmail.com> wrote: >> >> > Massive +1 for switching to space indention. Makes the code render >> > consistently across various viewers (e.g. Github UI, Apache >> infrastructure, >> > IDEs). >> > >> > 2015-03-18 1:29 GMT+01:00 Fabian Hueske <fhue...@gmail.com>: >> > >> > > Touching every file of the code would also be a good opportunity to >> > switch >> > > from tab to space indention. >> > > So if we enforce a strict style, we could also address this issue which >> > > causes discussions every now and then. >> > > >> > > 2015-03-16 21:53 GMT+01:00 Aljoscha Krettek <aljos...@apache.org>: >> > > >> > > > No, but I don't know whether that's possible. >> > > > >> > > > The style guide prescribes, for example, this: >> > > > >> > > > def foo( >> > > > a: Int, >> > > > b: String, >> > > > c: String) >> > > > >> > > > for methods with long parameter lists while a lot of people do this: >> > > > >> > > > def foo(a: Int, >> > > > b: String, >> > > > c: String) >> > > > >> > > > (IntelliJ also does this). >> > > > >> > > > The scalastyle rules I added supposedly check for the official scala >> > > > guide style but they allow both styles of methods. >> > > > >> > > > On Mon, Mar 16, 2015 at 5:37 PM, Till Rohrmann <trohrm...@apache.org >> > >> > > > wrote: >> > > > > Do we already enforce the official Scala style guide strictly? >> > > > > >> > > > > On Mon, Mar 16, 2015 at 4:57 PM, Aljoscha Krettek < >> > aljos...@apache.org >> > > > >> > > > > wrote: >> > > > > >> > > > >> I'm already always sticking to the official Scala style guide, >> with >> > > the >> > > > >> exception of 100 line length. >> > > > >> On Mar 16, 2015 3:27 PM, "Till Rohrmann" <trohrm...@apache.org> >> > > wrote: >> > > > >> >> > > > >> > +1 for stricter Java code styles. I haven't looked into the >> Google >> > > > Code >> > > > >> > Style but maybe we make it easier for new contributors if we >> > apply a >> > > > >> coding >> > > > >> > style which is somehow known. >> > > > >> > >> > > > >> > +1 for line length of 100 for Scala code. I think it makes code >> > > > review on >> > > > >> > GitHub easier. >> > > > >> > >> > > > >> > For the Scala style, we could stick to official style guidelines >> > > [1]. >> > > > >> > >> > > > >> > [1] http://docs.scala-lang.org/style/ >> > > > >> > >> > > > >> > On Mon, Mar 16, 2015 at 3:06 PM, Hermann Gábor < >> > > reckone...@gmail.com> >> > > > >> > wrote: >> > > > >> > >> > > > >> > > +1 for the stricter Java code styles. >> > > > >> > > >> > > > >> > > We should not forget about providing code formatter settings >> for >> > > > >> Eclipse >> > > > >> > > and Intellij IDEA (as mentioned above). >> > > > >> > > That would help a lot. >> > > > >> > > >> > > > >> > > (Of course if we'll use Google Code Style, they already >> provide >> > > such >> > > > >> > files >> > > > >> > > < >> > > > >> > > >> > > > >> > >> > > > >> >> > > > >> > > >> > >> https://code.google.com/p/google-styleguide/source/browse/trunk/intellij-java-google-style.xml >> > > > >> > > > >> > > > >> > > .) >> > > > >> > > >> > > > >> > > On Mon, Mar 16, 2015 at 2:45 PM Alexander Alexandrov < >> > > > >> > > alexander.s.alexand...@gmail.com> wrote: >> > > > >> > > >> > > > >> > > > +1 for not limiting the line length. >> > > > >> > > > >> > > > >> > > > 2015-03-16 14:39 GMT+01:00 Stephan Ewen <se...@apache.org>: >> > > > >> > > > >> > > > >> > > > > +1 for not limiting the line length. Everyone should have >> a >> > > good >> > > > >> > sense >> > > > >> > > to >> > > > >> > > > > break lines. When in exceptional cases people violate >> this, >> > it >> > > > is >> > > > >> > > usually >> > > > >> > > > > for a good reason. >> > > > >> > > > > >> > > > >> > > > > On Mon, Mar 16, 2015 at 2:18 PM, Maximilian Michels < >> > > > >> m...@apache.org> >> > > > >> > > > > wrote: >> > > > >> > > > > >> > > > >> > > > > > +1 for enforcing a more strict Java code style. However, >> > > let's >> > > > >> not >> > > > >> > > > > > introduce a line legth of 100 like in Scala. I think >> > that's >> > > > >> hurting >> > > > >> > > > > > readability of the code. >> > > > >> > > > > > >> > > > >> > > > > > On Sat, Mar 14, 2015 at 4:41 PM, Ufuk Celebi < >> > > u...@apache.org> >> > > > >> > wrote: >> > > > >> > > > > > >> > > > >> > > > > > > On Saturday, March 14, 2015, Aljoscha Krettek < >> > > > >> > aljos...@apache.org >> > > > >> > > > >> > > > >> > > > > > wrote: >> > > > >> > > > > > > >> > > > >> > > > > > > > I'm in favor of strict coding styles. And I like the >> > > > google >> > > > >> > > style. >> > > > >> > > > > > > >> > > > >> > > > > > > >> > > > >> > > > > > > +1 I would like that. We essentially all agree that we >> > > want >> > > > >> more >> > > > >> > > > > > > homogeneity and I think strict rules are the only way >> to >> > > go. >> > > > >> > Since >> > > > >> > > > this >> > > > >> > > > > > is >> > > > >> > > > > > > a very subjective matter it makes sense to go with >> > > something >> > > > >> > > > (somewhat) >> > > > >> > > > > > > well >> > > > >> > > > > > > established like the Google code style. >> > > > >> > > > > > > >> > > > >> > > > > > >> > > > >> > > > > >> > > > >> > > > >> > > > >> > > >> > > > >> > >> > > > >> >> > > > >> > > >> > >>
