It can only be used for projects that don't have any rules at all, i.e.
they are purely using Meson to:
- configure files
- run (script?) tests
- install files that exist by the end of the setup stage
This can be useful e.g. for Meson itself, a pure python project.
In commit 97a72a1c53 we started to allow
cmakedefine with 3 tokens, as cmake expects (unlike mesondefine). This
would silently start working even if the declared minimum version was
older than 0.54.1
We need to know the project minimum version before evaluating the rest
of the function. There's three basic approaches:
- try to set it inside KwargInfo
- just run a minimal version of func_project for this, then load
everything after
- drop down to the AST and set it before anything else
In order to handle FeatureNew emitted by a FunctionNode evaluated
before project() due to being inlined, such as `version: run_command()`,
only option 3 suffices, the rest all happen way too late. Since we have
just added AST handling support for erroring out, we can do that to set
the version as well.
If the meson.build file is sufficiently "broken", even attempting to lex
and parse it will totally fail, and we error out without getting the
opportunity to evalaute the project() function. This can fairly easily
happen if we add new grammar to the syntax, which old versions of meson
cannot understand. Setting a minimum meson_version doesn't help, because
people with a too-old version of meson get parser errors instead of
advice about upgrading meson.
Examples of this include adding dict support to meson.
There are two general approaches to solving this issue, one of which
projects are empowered to do:
- refactor the project to place too-new syntax in a subdir() loaded
build file, so the root file can be interpreted
- teach meson to catch errors in building the initial AST, and just load
enough of the AST to check for meson_version advice
This implements the latter, allowing to future-proof the build
grammar.
Suppressing all exceptions was hidding even syntax errors in compiler
source code. If a compiler cannot be found, a MesonException is raised,
we should only expect that type.
If someone specifies a binary in a machine file, but the resulting
prog.found() is false because it doesn't actually exist on disk, then
the user was probably trying to disable finding that program. But
find_program() currently doesn't distinguish between a machine file
lookup returning a not-found program, and returning a dummy program
because there's no entry at all.
Explicitly check for a dummy program, rather than checking if the
program was found, before deciding whether to discard the lookup results
and continue trying other program lookup methods.
Include a frivolous error message too. We never see it, but if someone
reads the code and wonders why on *earth* there's a DSL function to
raise a RuntimeError, the message string will clue them in.
We have to allow through build.BuildTarget and build.ExtractedObjects,
which is what our previous level of checking did, even though they are
ignored. I've used FeatureDeprecated calls here, so that we have a clear
time of "this was officially deprecated in 1.1.0"
Hook this up to installed dependency manifests. This is often needed
above and beyond just an SPDX string -- e.g. many licenses have custom
copyright lines.
T.Sequence is a questionable concept. The idea is to hammer out generic,
maximally forgiving APIs that operate on protocols, which is a fancy way
of saying "I don't care if you use tuples or lists". This is rarely
needed, actually, and in exchange for this fancy behavior you get free
bugs.
Specifically, `somestr` is of type `T.Sequence[str]`, and also
`somestr[0]` is another string of type you guessed it. It's ~~turtles~~
strings all the way down.
It's worth noting that trying to code for "protocols" is a broken
concept if the contents have semantic meaning, e.g. it operates on
"the install tags of this object" rather than "an iterable that supports
efficient element access".
The other way to use T.Sequence is "I don't like that T.List is
invariant, but also I don't like that T.Tuple makes you specify exact
ordering". This sort of works. In fact it probably does work as long as
you don't allow str in your sequences, which of course everyone allows
anyway.
Use of Sequence has cute side effects, such as actually passing lists
around, knowing that you are going to get a list and knowing that you
need to pass it on as a list, and then having to re-allocate as
`list(mylist)` "because the type annotations says it could be a str or
tuple".
Except it cannot be a str, because if it is then the application is
fatally flawed and logic errors occur to disastrous end user effects,
and the type annotations:
- do not enforce their promises of annotating types
- fail to live up to "minimal runtime penalties" due to all the `list()`
Shun this broken concept, by hardening the type annotations. As it turns
out, we do not actually need any of this covariance or protocol-ism for
a list of strings! The whole attempt was a slow, buggy waste of time.
When auto-generating e.g. a `clang-format` target, we first check to see
if the user has already defined one, and if so we don't bother creating
our own. We check for two things:
- if a ninja target already exists, skip
- if a run_target was defined, skip
The second check is *obviously* a duplicate of the first check. But the
first check never actually worked, because all_outputs was only
generated *after* generating all utility rules and actually writing out
the build.ninja file. The check itself compares against nothing, and
always evaluates to false no matter what.
Fix this by reordering the target creation logic so we track outputs
immediately, but only error about them later. Now, we no longer need to
special-case run_target at all, so we can drop that whole logic from
build.py and interpreter.py, and simplify the tracked state.
Fixes defining an `alias_target()` for a utility, which tried to
auto-generate another rule and errored out. Also fixes doing the same
thing with a `custom_target()` although I cannot imagine why anyone
would want to produce an output file named `clang-format` (unless clang
itself decided to migrate to Meson, which would be cool but feels
unlikely).
Since it's also used in the rust module, it should be in a common place.
Also rename from `TEST_KWARGS` to `TEST_KWS`, which is more in line with
the `*_KW` naming scheme used in the type_checking module.
This finds uses of deny-listed functions, which defaults to map and
filter. These functions should be replaced by comprehensions in
idiomatic python because:
1. comprehensions are more heavily optimized and are often faster
2. They avoid the need for lambdas in some cases, which make them
faster
3. you can do the equivalent in one statement rather than two, which
is faster
4. They're easier to read
5. if you need a concrete instance (ie, a list) then you don't have
to convert the iterator to a list afterwards
Regression test: libccpp has both C and C++ sources. The executable only
has C sources. It should still link using the C++ compiler. When using
both_libraries the static has no sources and thus no compilers,
resulting in the executable linking using the C compiler.
https://github.com/Netflix/vmaf/issues/1107
This was introduced in commit 3a6e2aeed9
as part of 0.50.0, but did not contain a FeatureNew. As a result, people
would use it without realizing that they broke support for versions of
Meson included in their minimum requirements.
This is based on searching for `@FeatureNew*` decorators.
There is also one correction to a version in a decorators;
`build_by_default` was added in #1303, which is 0.38.0, not 0.40.0.
When using both_libraries(), or library() with default_library=both, we
remove all sources from args and kwargs when building the static
library, and replace them by the objects from the shared library. But
sources could also come from any InternalDependency, in which case we
currently build them twice (not efficient) and link both objects into
the static library.
It also means that when we needlessly build those source for the static
library, it miss order dependency on generated headers that we removed
from args/kwargs, which can cause build errors in the case the source
from static lib is compiled before the header in shared lib gets
generated.
This happened in GLib:
https://gitlab.gnome.org/GNOME/glib/-/merge_requests/2917.
To differentiate it from the function parameter itself. Annotating a
function as
```
def func_foo(kwargs: kwargs.FooKwargs):
```
is confusing, both visually and to static linters.
Strictly speaking code restructuring isn't needed, but making this PEP8
compliant results in indentation of the code that reduces the
readability. By moving the offending code on the outside of the method
call, the readability is maintained.
This is generally a bad idea, e.g. it causes OSError on freebsd.
It also gets ignored by solaris and thus causes unittest failures.
The proper solution is to simply reject any attempt to set this, and log a
warning.
The install_emptydir function does apply the mode as well, and since it
is a directory it actually does something. This is the only place where
we don't reset the mode.
Although install_subdir also installs directories, and in theory it
could set the mode as well, that would be a new feature. Also it doesn't
provide much granularity and has mixed semantics with files. Better to
let people use install_emptydir + install_subdir.
Fixes#5902
Generally plumb through the values of get_option() passed to
install_dir, and use this to establish the install plan name. Fixes
several odd cases, such as:
- {datadir} being prepended to "share" or "include"
- dissociating custom install directories and writing them out as
{prefix}/share/foo or {prefix}/lib/python3.10/site-packages
This is the second half of #9478Fixes#10601
`configure_file` is both an extremely complicated implementation, and
a strange place for copying. It's a bit of a historical artifact, since
the fs module didn't yet exist. It makes more sense to move this to the
fs module and deprecate this `configure_file` version.
This new version works at build time rather than configure time, which
has the disadvantage it can't be passed to `run_command`, but with the
advantage that changes to the input don't require a full reconfigure.
This was never meant to work, it's an implementation detail of using
`importlib.import_module` and that our modules used to be named
`unstable_` that this ever worked.
Thanks to `ModuleInfo`, all modules are just named `foo.py` instead of
`unstable_foo.py`, which simplifies the import method a bit. This also
allows for accurate FeatureNew/FeatureDeprecated use, as we know when
the module was added and if/when it was stabilized.
Instead of using FeatureNew/FeatureDeprecated in the module.
The goal here is to be able to handle information about modules in a
single place, instead of having to handle it separately. Each module
simply defines some metadata, and then the interpreter handles the rest.
This error message was quite confusing when triggered by
use of an absolute path to the include dir of an external dependency
(numpy in my case). Changing that to a relative dir also isn't
a solution, because Meson will *not* do the "busywork to make paths
work" that the error message says it will.
Eli Schwartz
Dylan Baker
Xavier Claessens
Paolo Bonzini
Michael Champanis
David Robillard
Tristan Partin
Elliott Sales de Andrade
Thomas Li
Alf Henrik Sauge
Daniel Mensinger
Ralf Gommers