Dotty has its own logic for displaying problems with the proper file
path, position, and caret, but if we store this information in
Problem#message we end up with duplicated information in the output
since Zinc will prepend/append similar things (see
sbt.internal.inc.ProblemStringFormats). So far, we worked around this in
Dotty by using an empty position in the sbt bridge reporter, but this
means that crucial semantic information that could be used by a Build
Server Protocol implementation and other tools is lost. This commit
allows us to avoid by adding an optional `rendered` field to `Problem`:
when this field is set, its value controls what the user sees, otherwise
we fallback to the default behavior (the logic to do this will be added to
Zinc after this PR is merged and a new release of sbt-util is made).
Positions in the Language Server Protocol and Build Server Protocol are
line/column-based instead of offset-based, so this is more convenient.
Computing the line/column from the offset is possible but requires
reading the source file.
A position now has a start, an end, and a point (the existing `offset`),
just like it does in the Scala compiler. This information is especially
useful for displaying squiggly lines in an IDE.
This commit and the next one are required for https://github.com/sbt/zinc/pull/571
`F0`, `F1` and `Maybe` have become useless since Java 8 introduced
`Supplier`, `Function` and `Optional` in the default Java 8 standard
library.
Therefore, they are not necessary anymore. This change is required to
change some Zinc's and sbt APIs. They are not widely used, so the
changes will be small.
* Make Nothing a singleton
* Make Maybe's constructor private
* Optimise equals to use reference equality first
* Optimise Just.equals by having proper, non-anonymous subclasses
* Having non-anonymous subclasses makes them have nicer classnames
* Give Just a value() method
Ethan Atkins
Guillaume Martres
jvican
Eugene Yokota
Dale Wijnand
Martin Duhem