We try to backtrack through the filesystem to find the correct directory
to build in, and suggest this as a possible diagnostic. However, our
current heuristic relies on parsing the raw file with string matching to
see if it starts with `project(`, and this may or may not actually work.
Instead, do a bit of recursion and parse each candidate with mparser,
then check if the first node of *that* file is a project() function.
This makes us resilient to a common case: where the root meson.build is
entirely valid, but, the first line is a comment containing e.g. SPDX
license headers and a simple string comparison simply does not cut it.
Fixes the bad error message from #12441, which was supposed to provide
more guidance but did not.
Performed using https://github.com/ilevkivskyi/com2ann
This has no actual effect on the codebase as type checkers (still)
support both and negligible effect on runtime performance since
__future__ annotations ameliorates that. Technically, the bytecode would
be bigger for non function-local annotations, of which we have many
either way.
So if it doesn't really matter, why do a large-scale refactor? Simple:
because people keep wanting to, but it's getting nickle-and-dimed. If
we're going to do this we might as well do it consistently in one shot,
using tooling that guarantees repeatability and correctness.
Repeat with:
```
com2ann mesonbuild/
```
This detects cases where module A imports a function from B, and C
imports that same function from A instead of B. It's not part of the API
contract of A, and causes innocent refactoring to break things.
During evaluation of codeblocks, we start off with an iteration of
nodes, and then while evaluating them we may update the global
self.current_node context. When catching and formatting errors, we
didn't take into account that the node might be updated from the
original top-level iteration.
Switch to formatting errors using self.current_node instead, to ensure
we can point at the likely most-accurate actual cause of an error.
Also update the current node in a few more places, so that function
calls always see the function call as the current node, even if the most
recently parsed node was an argument to the function call.
Fixes#11643
If we add new kwargs to a function invoked on the first line, we also
need to validate the meson_version before erroring out due to unknown
kwargs. Even if the AST was successfully built.
Amusingly, we also get to improve the error message a bit. By passing
the AST node instead of an interpreter node, we get not just line
numbers, but also column offsets of the issueful meson_version. That
broke the stdout of another failing test; adapt it.
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.
This can be triggered if someone tries to call a non-ID. The example
reproducer was:
```
if (var = dependency(...)).found()
```
This produced a traceback ending in
```
raise InvalidArguments(f'Variable "{object_name}" is not callable.')
UnboundLocalError: local variable 'object_name' referenced before assignment
```
After this commit, the error is reported as:
```
ERROR: AssignmentNode is not callable.
```
+ Extend the parser to recognize the multiline f-strings, which the
documentation already implies will work.
The syntax is like:
```
x = 'hello'
y = 'world'
msg = f'''This is a multiline string.
Sending a message: '@x@ @y@'
'''
```
which produces:
```
This is a multiline string.
Sending a message: 'hello world'
```
+ Added some f-string tests cases to "62 string arithmetic" to exercise
the new behavior.
These are only used for type checking, so don't bother importing them at
runtime.
Generally add future annotations at the same time, to make sure that
existing uses of these imports don't need to be quoted.
Use a derived type when passing `subproject` around, so that mypy knows
it's actually a SubProject, not a str. This means that passing anything
other than a handle to the interpreter state's subproject attribute
becomes a type violation, specifically when the order of the *four*
different str arguments is typoed.
This is the final refactoring for extracting the bultin object
logic out of Interpreterbase. I decided to do both arrays and
dicts in one go since splitting it would have been a lot more
confusing.
Another commit in my quest to rid InterpreterBase from all higher
level object processing logic.
Additionally, there is a a logic change here, since `str.join` now
uses varargs and can now accept more than one argument (and supports
list flattening).
Since it cannot resolve `import typing as T` in order to figure out that
T.* is doing annotation-worthy stuff.
Since T.cast('Foo') is not actually using Foo except in an annotation
context (due to being a string) it requires extra work to resolve, and
the only thing that would currently work is actually using
'typing.cast'. However, we have decided to not use it except as T...
Since this import is only imported during mypy it's not so bad to noqa
it.
We have a lot of these. Some of them are harmless, if unidiomatic, such
as `if (condition)`, others are potentially dangerous `assert(...)`, as
`assert(condtion)` works as expected, but `assert(condition, message)`
will result in an assertion that never triggers, as what you're actually
asserting is `bool(tuple[2])`, which will always be true.
Follow-up on commit 5a7b8d86d0
Sometimes, we find a parent meson.build which is also malformed, and we
shouldn't suggest that maybe the user meant to use that, if it isn't a
valid project() either. Do a rough and dirty check to see if the very
first line is a project() declaration, and if not, don't try to be
clever and suggest using it.
The "invalid source tree" error suffices here, since we're not
absolutely sure meson can be successfully run in that parent directory
and actually advising people about the wrong location is a lot more
confusing than just saying "please figure this out yourself, here is
what to look for".
Granted, we miss cases where project() comes after blank lines and/or
comments, but doing a full AST parse here is excessively overkill and
probably too painful to do, and we don't need to be *that* clever. So
let's be content with merely going above and beyond the call of duty.
Explicitly mention that the project definition is invalid, and clarify
that project is `project()` -- a function.
Also try to walk the directory tree upward, and if there are parent
meson.build files, just say this isn't the project root, and "maybe you
meant to run meson there instead?"
This won't catch calls to subdir('foo/bar') but we can't be perfect,
only better than before and catch the *majority* of such cases, and
hopefully it's a lot more clear if meson protests that the project is
"invalid, there is no project() function", where the user should look
for a potential solution.
Fixes#3426
This commit introduces a new type of `HoldableObject`: The
`SecondLevelHolder`. The primary purpose of this class is
to handle cases where two (or more) `HoldableObject`s are
stored at the same time (with one default object). The
best (and currently only) example here is the `BothLibraries`
class.