The compiler now provides a server protocol for an interactive session
with another process. The build runner uses this protocol to communicate
compilation errors semantically from zig compiler subprocesses to the
build runner.
The protocol is exposed via stdin/stdout, or on a network socket,
depending on whether the CLI flag `--listen=-` or e.g.
`--listen=127.0.0.1:1337` is used.
Additionally:
* add the zig version string to the build runner cache prefix
* remove --prominent-compile-errors CLI flag because it no longer does
anything. Compilation errors are now unconditionally displayed at the
bottom of the build summary output when using the terminal-based
build runner.
* Remove the color field from std.Build. The build steps are no longer
supposed to interact with stderr directly. Instead they communicate
semantically back to the build runner, which has its own logic about
TTY configuration.
* Use the cleanExit() pattern in the build runner.
* Build steps can now use error.MakeFailed when they have already
properly reported an error, or they can fail with any other error
code in which case the build runner will create a simple message
based on this error code.
* Step.init() now takes an options struct
* Step.init() now captures a small stack trace and stores it in the
Step so that it can be accessed when printing user-friendly debugging
information, including the lines of code that created the step in
question.
RunStep is supposed to auto-detect whether the intend is for
side-effects or for producing an output file. The auto-detection logic
was incorrect, and this commit fixes it.
I tested this manually locally. Automated testing will require a more
significant investment in the test harness, which I will work on in a
future enhancement.
closes#14666
* Use std.Build.Cache.Directory instead of a string for storing the
cache roots and build roots.
* Set up a std.Build.Cache in build_runner.zig and use it in
std.Build.RunStep for avoiding redundant work.
This provides file path as a command line argument to the command being
run, and returns a FileSource which can be used as inputs to other APIs
throughout the build system.
Unfortunately, it is implemented by pooping a ton of temporary files
into zig-cache/tmp for the time being. I think one of the very next
improvements to the build system should be moving the compiler's cache
system to the standard library and using it in the build system. I had a
look at the dependencies and it is already pretty untangled.
Usage of `catch unreachable` in build scripts is completely harmless
because build scripts are always run in Debug mode, however, it sets a
poor example for beginners to learn from.
