how to configure SBT to pick the desired scala version (2.9) - scala

While creating a project with sbt command it always prompts for the 2.7.X version of scala however I have 2.9.0 and sbt 0.7.7 installed is there a way to configure sbt to pick 2.9 by default.

If you use sbt version 0.10 instead it has changed a bit, in the build.sbt file you specify scalaVersion := "2.9.0-1" (default seem to be 2.8.1)
See Migrating from SBT 0.7.x to 0.10.x or Quick Configuration Examples. The Full configuration example shows Scala style configuration.
Threre is a ~/.sbt/plugins/ library where you store global plugins. But I do not yet know if you can define a global build properties.

In your project directory there should be a file called build.properties. There you can configure SBT to use whatever version you want. When you change the file either exit SBT or use the command reload.

Related

sbteclipse not adding generated source folders to java build path?

I ran sbt eclipse on a Scala Project and when I imported it into Scala IDE(4.0.0 RC2), it gave me a type not found error as the types referred to were actually auto-generated code which were at target/scala-2_10/src_managed/main/compiled_avro/org/... I was able to do a sbt compile at the console though.
I got it to compile by adding the above folder to the Java Build Path.
My question is that since sbt eclipse can already detect Java Projects which the current project depends on and since sbt compile works at the console, should sbt eclipse be able to figure out dependencies to source folders of generated code as well? or maybe such a feature exists and I just don't know about it?
This may not be the correct way of doing things but to fix the issue i did the following.
sbt avro:compile
sbt compile
sbt eclipse
In eclipse i right clicked on target/scala-*/src_managed/main/compiled_avro > build path > use as source folder
The sbteclipse way:
Edit your project or global build.sbt file. My global ~/.sbt/0.13/build.sbt contains:
import com.typesafe.sbteclipse.plugin.EclipsePlugin._
EclipseKeys.createSrc := EclipseCreateSrc.Default + EclipseCreateSrc.Managed
I'm using an older version of _sbteclipse, version 2.5.0 (various non-relevant reasons), which seems to require both the import and a single blank link between each line of real content (this drives me a bit crazy, yes). I don't believe the import is required for newer versions of sbteclipse.
sbt clean avro:compile compile
sbt eclipse

Do you need to install Scala separately if you use sbt?

Reason I ask, is because it's possible to specify a Scala version in the build.sbt file (using scalaVersion setting), and once you do that, sbt will automatically download that Scala version to use with the project.
I also seem to remember that despite having Scala 2.11.1 on my system, sbt would compile and run with Scala 2.10 if no version was specified.
So the question is, do I need to install Scala separately if I got sbt installed?
No you don't need it. sbt will download Scala for you.
If you install sbt-extras (basically just a script) you don't even need to download sbt: it will automatically download the sbt launcher you need. Very handy since you just need to specify sbt.version in your build.properties and you're good to go.
Edit: removed my comment about not being able to do sbt console in an empty directory, since both sbt and sbt-extras support it now.

How do i change the Scala version that sbt works with?

Firing up the SBT console it reads :
[info] Building project AYLIEN 1.0 against Scala 2.8.1
[info] using MyProject with sbt 0.7.4 and Scala 2.7.7
How can I make it use MyProject with sbt 0.7.4 and Scala 2.8.1 ? Please pay attenetion that I'm not asking about the Scala version that is used to build my project (it is the 2.8.1 as you can see), but I rather want to make sbt use MyProject with Scala 2.8.1. Apparently sbt uses it's own scala version to work with project definition (MyProject here) which is different than one it uses to actually build the project! or perhaps I'm missing something ... ?
I can see your concern about SBT still using 2.7.7 internally, but it doesn't really matter since SBT downloads that version on its own. You do not have to install 2.7.7 or anything, just forget about it and pretend your environment is pure Scala 2.8.
The configuration file that holds the SBT version setting is: project/build.properties. The content looks like this:
project.organization=com.ab.web
project.name=cool_proj
sbt.version=0.7.4
project.version=1.0
build.scala.versions=2.8.0
project.initialize=false
When you want to move up to the next SBT version, just change 0.7.4 to that version and SBT will update itself. Eventually SBT will use some other Scala version internally, but this will not matter to the user.
SBT 0.7.* won't work with Scala 2.8.* for your project definition.
Mark Harrah is currently working on the next version of SBT which will work with 2.8.*. This means that you can't use any Scala features or functionality that was added after Scala 2.7.7 in your project definition or plugins. Your project itself is free to use 2.8.*.

How to create SBT project with IntelliJ Idea?

I just got started with Scala/LiftWeb/Sbt developing, and I'd like to import a Sbt project in IntelliJ Idea.
Actually, I managed to import my project in two different ways:
1) with Maven. I created a Maven project, and of top of that I created a Sbt project, which I then imported in IntelliJ. I could then easily start, stop the jetty server, and do other stuff.
But that's not what I want. I want to do the same stuff, just Maven-free.
That lead me to
2) with Eclipse. So, I created a new Sbt project (with a little script I wrote, configuring the Sbt project to be a WebProject). I used then the sbt-eclipsify plugin to 'convert' the project for Eclipse, which I then imported in IntelliJ (existing source -> eclipse).
But the problems started here: I cannot get the IntelliJ Sbt plugin to work.
Can anyone help me with this?
There are three basic ways how to create a project - modern versions of IntelliJ can import sbt project out of the box, otherwise you can either use sbt plugin to generate IntelliJ project, or use IntelliJ Scala plugin to create sbt project. Basic features work out of the box using both solutions, some complex builds can have problems, so try other tools to see if it works there.
IntelliJ
IntelliJ IDEA has become so much better these days. The current version (14.0.2) supports sbt projects out of the box with the Scala plugin. Just install the plugin and you should be able to open up Scala/sbt projects without any troubles.
With the plugin, just point at a sbt project and IDEA is going to offer you a wizard to open that kind of project.
IntelliJ Scala Plugin
IntelliJ plugin can be found here
http://confluence.jetbrains.com/display/SCA/Scala+Plugin+for+IntelliJ+IDEA or can be installed directoly from within the IDE using Settings -> Plugins dialog. Afterwards one can just do File -> New Project -> Scala -> SBT based. IntelliJ will generate basic build.sbt, download necessary dependencies and open project.
SBT Plugin
Sbt plugin that generate an idea project based on the sbt files can be found here: https://github.com/mpeltonen/sbt-idea
SBT 12.0+ & 13.0+
Simply add addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.5.2") to your build.sbt; no additional resolvers are needed.
Older Versions:
SBT 0.11+
Create and add the following lines to ~/.sbt/plugins/build.sbt OR PROJECT_DIR/project/plugins.sbt
resolvers += "sbt-idea-repo" at "http://mpeltonen.github.com/maven/"
addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.6.0")
Use gen-idea in sbt to create IDEA project files.
By default, classifiers (i.e. sources and javadocs) of sbt and library dependencies are loaded if found and references added to IDEA project files. If you don't want to download/reference them, use command gen-idea no-classifiers no-sbt-classifiers.
SBT 0.10.1
(according to the plugin author, 0.10.0 won't work!)
Create and add the following lines to ~/.sbt/plugins/build.sbt:
resolvers += "sbt-idea-repo" at "http://mpeltonen.github.com/maven/"
libraryDependencies += "com.github.mpeltonen" %% "sbt-idea" % "0.10.0"
Use gen-idea sbt task to create IDEA project files.
By default, classifiers (i.e. sources and javadocs) of sbt and library dependencies are loaded if found and references added to IDEA project files. If you don't want to download/reference them, use command gen-idea no-classifiers no-sbt-classifiers.
SBT 0.7
To use it, simply run this from your sbt shell, it will use the plugin as an external program:
> *sbtIdeaRepo at http://mpeltonen.github.com/maven/
> *idea is com.github.mpeltonen sbt-idea-processor 0.4.0
...
> update
...
> idea
...
You can also add trait in your project definition, as you want:
import sbt._
class MyProject(info: ProjectInfo) extends ParentProject(info) with IdeaProject {
lazy val mySubProject = project("my-subproject", "my-subproject", new DefaultProject(_) with IdeaProject)
// ...
}
For now I do this by hand. It is quite simple.
Create the project with SBT
Create a new IDEA Project with the same root path
Create a module with the same root path
Set src/main/scala as a src path on the module
Set src/test/scala as a test path on the module
Add scala-library.jar as a library
Add lib (if it is present) as a jar directory within a module library
Add lib_managed/compile (if it is present) as a jar directory within a module library
Add lib_managed/test (if it is present) as a jar directory within a module library
That's it from memory. It would be better if it were automated, but it's no big deal as it is now.
One note of caution: The above approach doesn't work well with new-school sbt, i.e. versions 0.10 and newer, because it doesn't copy dependencies into lib_managed by default. You can add
retrieveManaged := true
to your build.sbt to make it copy the dependencies into lib_managed.
Tempus fugit and IntelliJ IDEA has become so much better these days. It's 2015 after all, isn't it?
Having said that, the latest version of IntelliJ IDEA 14.0.2 supports sbt projects out of the box with the Scala plugin. Just install the plugin and you should be able to open up Scala/sbt projects without much troubles.
I'm using the Early Access version of the plugin which is 1.2.67.6.EAP as of the time of the writing.
With the plugin just point at a sbt project and IDEA is going to offer you a wizard to open that kind of project.
About sbt-idea in sbt 0.12.4
For sbt 0.12.4 the system-wide plugin configuration file - ~/.sbt/plugins/build.sbt or PROJECT_DIR/project/plugins.sbt - should have the following lines:
resolvers += "Sonatype snapshots" at "http://oss.sonatype.org/content/repositories/snapshots/"
addSbtPlugin(dependency="com.github.mpeltonen" % "sbt-idea" % "1.5.0-SNAPSHOT")
Run sbt gen-idea to generate IDEA project files.
Read the sbt-idea plugin website for more up-to-date information. You may also find my blog entry Importing sbt-based project to IntelliJ IDEA 13 (with sbt-idea, Scala 2.11 and sbt 0.12) useful.
For sbt 0.7
See the answer elsewhere on this page.
For sbt 0.10
Clone and build Ismael's sbt-idea:
git clone https://github.com/ijuma/sbt-idea.git
cd sbt-idea
git checkout sbt-0.10
./sbt package
Create an sbt plugin lib directory if you don't have one already
mkdir -p ~/.sbt/plugins/lib
Copy the jar built in step one into here
cp sbt-idea/target/scala-2.8.1.final/*.jar ~/.sbt/plugins/lib
Restart or reload sbt, then you can run gen-idea (or gen-idea with-classifiers if you want sources and javadoc in intelliJ too)
Source: Tackers' suggestion on the message group.
In IntelliJ IDEA 13.x itself
You can open an SBT-based project in IDEA nowadays. It will create the necessary project and modules, and keep your dependencies up-to-date whenever you make changes to the build scripts.
I just went through all this pain. I spend days trying to get an acceptable environment up and have come to the conclusion that ENSIME, SBT and JRebel are going to be my development environment for some time. Yes, it is going back to Emacs, but ENSIME turns it into a bit or an idea with refactoring, debugging support, navigation, etc. It's not nowhere near as good as Eclipse (Java), but unless the scala plugins work better it's the best we have.
Until the Scala development environments get up to snuff (Eclipse or IntelliJ) I'm not going to bother. They're just way too buggy.
See the discussion on the lift site.
http://groups.google.com/group/liftweb/browse_thread/thread/6e38ae7396575052#
Within that thread, there is a link to a HOWTO for IntelliJ, but although it kinda works, there are many issues that render it a little less that useful.
http://blog.morroni.com/2010/07/14/setup-intellij-9-for-lift-framework-development/comment-page-1/
The answers are old for 2014.
In IntelliJ 13.x, the plugin Scala is ver 0.41.2 ( SBT is included).
My SBT version is 0.13.5 (terminal : sbt sbtVersion )
Go to the project's root folder and enter in the terminal
sbt idea
You will see two new hidden folders .idea and .idea_modules.
Then in IntelliJ, File > Open > select the project.
It should open the project without any problem.
Before you start creating your SBT project, make sure that the Scala plugin is downloaded and enabled in IntelliJ IDEA.
below link explains everything you need to know.
https://www.jetbrains.com/help/idea/2016.1/getting-started-with-sbt.html

How to change Scala version for sbt project?

How can I change Scala version in a sbt project?
I would like SBT to check whether the system's Scala version is correct and if it is not the case then download it.
xsbt (0.10+, including the latest 0.13.7)
Change scalaVersion in build.sbt to whatever Scala version your project should be using - see .sbt build definition.
scalaVersion := "2.10.1"
sbt:
As mentioned in RunningSBT, you can:
You can temporarily switch to another version of Scala using ++<version>.
This version does not have to be listed in your build.scala.versions property, but it does have to be in a repository or be a local Scala version you have defined.
But the CrossBuild page is more suited for what you want, as it shows in action how to change the build.scala.versions property.
So you should be able to
set build.scala.versions 2.7.7
reload
set build.scala.versions 2.8.0.RC2
reload
and each time trigger a compilation with a different Scala version.