cargo: Fix feature resolution

Introduce a global Cargo interpreter state that keeps track of enabled
features on each crate.

Before generating AST of a Cargo subproject, it downloads every
sub-subproject and resolves the set of features enabled on each of them
recursively. When it later generates AST for one its dependencies, its
set of features and dependencies is already determined.

1 files changed, 3 insertions, 0 deletions

diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index 2621b9ca2..81a23404a 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -45,6 +45,7 @@ if T.TYPE_CHECKING:
 
     from .compilers import Compiler
     from .wrap.wrap import Resolver
+    from . import cargo
 
     CompilersDict = T.Dict[str, Compiler]
 
@@ -687,6 +688,8 @@ class Environment:
         self.default_cmake = ['cmake']
         self.default_pkgconfig = ['pkg-config']
         self.wrap_resolver: T.Optional['Resolver'] = None
+        # Store a global state of Cargo dependencies
+        self.cargo: T.Optional[cargo.Interpreter] = None
 
     def _load_machine_file_options(self, config: 'ConfigParser', properties: Properties, machine: MachineChoice) -> None:
         """Read the contents of a Machine file and put it in the options store."""