sbt/notes

Goals/Guidelines for xsbt
=====
As usual:
 - Immutable interfaces
 - Typesafe
 - Robust, flexible API

ISSUES
 - Scala issue #2265: cannot use structural types or libraries that use structural types, or OOME: PermGen will occur.  Running/testing user code with structural types might also cause OOME, but is unlikely unless the Scala standard library or compiler uses structural types.

TODO
 - immutable LinkedSet that preserves order of section declarations for repositories and app.properties
 - launcher interface versioning

Task engine
- method tasks will be normal tasks that pull the command line from a CommandLine task
- possibly have per task logging, including configuration (e.g. 'debug compile')
- unnamed tasks log to parent task
- in parallel, optionally one task always logging

- Have Interfaces subproject that depends on no other project and defines interfaces in package xsbti.  They are written in Java and cannot refer to Scala classes (compileOrder = JavaThenScala).  These interfaces can be used to pass objects across ClassLoader boundaries.
- launcher/main interface is not static (no system properties should be used past the static entry point)
- simple, well-defined ClassLoaders
- use Exceptions instead of Option/Either
- every component gets its own subproject
- can use any version of compiler/Scala that is source compatible with the compiler-interface component
- Logger passed by implicit parameter
- build xsbt using normal cross-build conventions
- compiler: raw interface (no dependency analysis, but still in same jvm) or with dependency analysis
- compiler: can specify scala-library.jar and scala-compiler.jar + version instead of retrieving the ClassLoader
- minimal dependence on main xsbt logger from subcomponents: use thin interface for subcomponents

Dependency Management
- resolvers are completely defined in project definition (use Resolver.withDefaultResolvers)
- configurations completely defined within project (use ModuleConfiguration.configurations)

Launcher
- see launch.specification
- boot interface contains static final int version = N that main xsbt can use to check if it can be loaded by that version (a lower bound check)
- main xsbt has static final int version = N that boot can use to check if it can load that version (a lower bound check)
Initial xsbt commit 2009-08-16 20:29:08 +02:00			`Goals/Guidelines for xsbt`
			`=====`
			`As usual:`
			`- Immutable interfaces`
			`- Typesafe`
			`- Robust, flexible API`

Launcher documentation 2009-10-17 15:48:39 +02:00			`ISSUES`
			`- Scala issue #2265: cannot use structural types or libraries that use structural types, or OOME: PermGen will occur. Running/testing user code with structural types might also cause OOME, but is unlikely unless the Scala standard library or compiler uses structural types.`

			`TODO`
			`- immutable LinkedSet that preserves order of section declarations for repositories and app.properties`
			`- launcher interface versioning`

Initial xsbt commit 2009-08-16 20:29:08 +02:00			`Task engine`
			`- method tasks will be normal tasks that pull the command line from a CommandLine task`
			`- possibly have per task logging, including configuration (e.g. 'debug compile')`
			`- unnamed tasks log to parent task`
			`- in parallel, optionally one task always logging`

Launcher documentation 2009-10-17 15:48:39 +02:00			`- Have Interfaces subproject that depends on no other project and defines interfaces in package xsbti. They are written in Java and cannot refer to Scala classes (compileOrder = JavaThenScala). These interfaces can be used to pass objects across ClassLoader boundaries.`
			`- launcher/main interface is not static (no system properties should be used past the static entry point)`
Initial xsbt commit 2009-08-16 20:29:08 +02:00			`- simple, well-defined ClassLoaders`
			`- use Exceptions instead of Option/Either`
			`- every component gets its own subproject`
Launcher documentation 2009-10-17 15:48:39 +02:00			`- can use any version of compiler/Scala that is source compatible with the compiler-interface component`
Initial xsbt commit 2009-08-16 20:29:08 +02:00			`- Logger passed by implicit parameter`
Compilation with analysis independent of Scala version of sbt. Basic test for this. 2009-08-24 04:21:15 +02:00			`- build xsbt using normal cross-build conventions`
Launcher documentation 2009-10-17 15:48:39 +02:00			`- compiler: raw interface (no dependency analysis, but still in same jvm) or with dependency analysis`
Initial xsbt commit 2009-08-16 20:29:08 +02:00			`- compiler: can specify scala-library.jar and scala-compiler.jar + version instead of retrieving the ClassLoader`
Launcher documentation 2009-10-17 15:48:39 +02:00			`- minimal dependence on main xsbt logger from subcomponents: use thin interface for subcomponents`
Initial xsbt commit 2009-08-16 20:29:08 +02:00
			`Dependency Management`
			`- resolvers are completely defined in project definition (use Resolver.withDefaultResolvers)`
			`- configurations completely defined within project (use ModuleConfiguration.configurations)`
Setting up compiler support and several related additions to util/io * Added the top-level interface project for communicating across scala versions within a jvm. * Added plugin project containing analysis compiler plugin * Added component compiler to build xsbt components against required version of Scala on the fly * Added interface to compiler that runs in the same version of Scala * Added frontend that compiles against a given version of Scala with or without analysis. 2009-08-17 16:51:43 +02:00
New generalized launcher 2009-09-26 08:18:04 +02:00			`Launcher`
Turned sbt launcher into a general Scala application launcher as described in launch.specification 2009-09-27 20:39:26 +02:00			`- see launch.specification`
			`- boot interface contains static final int version = N that main xsbt can use to check if it can be loaded by that version (a lower bound check)`
			`- main xsbt has static final int version = N that boot can use to check if it can load that version (a lower bound check)`