cargo: pick version from Cargo.toml if not specified in a dependency

Extracted from a patch by Xavier Claessens <xclaessens@netflix.com>

Author: bonzini

mesonbuild/cargo/interpreter.py

@@ -160,7 +160,7 @@ def _fetch_package_from_subproject(self, package_name: str, meson_depname: str)
                 self._add_dependency(pkg, depname)
         return pkg, False
 
-    def _dep_package(self, dep: Dependency) -> PackageState:
+    def _dep_package(self, pkg: PackageState, dep: Dependency) -> PackageState:
         if dep.git:
             _, _, directory = _parse_git_url(dep.git, dep.branch)
             dep_pkg, _ = self._fetch_package_from_subproject(dep.package, directory)
@@ -203,7 +203,7 @@ def _add_dependency(self, pkg: PackageState, depname: str) -> None:
             # It could be build/dev/target dependency. Just ignore it.
             return
         pkg.required_deps.add(depname)
-        dep_pkg = self._dep_package(dep)
+        dep_pkg = self._dep_package(pkg, dep)
         if dep.default_features:
             self._enable_feature(dep_pkg, 'default')
         for f in dep.features:
@@ -227,7 +227,7 @@ def _enable_feature(self, pkg: PackageState, feature: str) -> None:
                     depname = depname[:-1]
                     if depname in pkg.required_deps:
                         dep = pkg.manifest.dependencies[depname]
-                        dep_pkg = self._dep_package(dep)
+                        dep_pkg = self._dep_package(pkg, dep)
                         self._enable_feature(dep_pkg, dep_f)
                     else:
                         # This feature will be enabled only if that dependency
@@ -237,7 +237,7 @@ def _enable_feature(self, pkg: PackageState, feature: str) -> None:
                     self._add_dependency(pkg, depname)
                     dep = pkg.manifest.dependencies.get(depname)
                     if dep:
-                        dep_pkg = self._dep_package(dep)
+                        dep_pkg = self._dep_package(pkg, dep)
                         self._enable_feature(dep_pkg, dep_f)
             elif f.startswith('dep:'):
                 self._add_dependency(pkg, f[4:])
@@ -302,7 +302,8 @@ def _create_dependencies(self, pkg: PackageState, build: builder.Builder) -> T.L
         ast: T.List[mparser.BaseNode] = []
         for depname in pkg.required_deps:
             dep = pkg.manifest.dependencies[depname]
-            ast += self._create_dependency(dep, build)
+            dep_pkg = self._dep_package(pkg, dep)
+            ast += self._create_dependency(dep_pkg, dep, build)
         ast.append(build.assign(build.array([]), 'system_deps_args'))
         for name, sys_dep in pkg.manifest.system_dependencies.items():
             if sys_dep.enabled(pkg.features):
@@ -336,10 +337,11 @@ def _create_system_dependency(self, name: str, dep: SystemDependency, build: bui
             ),
         ]
 
-    def _create_dependency(self, dep: Dependency, build: builder.Builder) -> T.List[mparser.BaseNode]:
-        pkg = self._dep_package(dep)
+    def _create_dependency(self, pkg: PackageState, dep: Dependency, build: builder.Builder) -> T.List[mparser.BaseNode]:
+        version_ = dep.meson_version or [pkg.manifest.package.version]
+        api = dep.api or pkg.manifest.package.api
         kw = {
-            'version': build.array([build.string(s) for s in dep.meson_version]),
+            'version': build.array([build.string(s) for s in version_]),
         }
         # Lookup for this dependency with the features we want in default_options kwarg.
         #
@@ -357,7 +359,7 @@ def _create_dependency(self, dep: Dependency, build: builder.Builder) -> T.List[
             build.assign(
                 build.function(
                     'dependency',
-                    [build.string(_dependency_name(dep.package, dep.api))],
+                    [build.string(_dependency_name(dep.package, api))],
                     kw,
                 ),
                 _dependency_varname(dep.package),
@@ -387,7 +389,7 @@ def _create_dependency(self, dep: Dependency, build: builder.Builder) -> T.List[
                 build.if_(build.not_in(build.identifier('f'), build.identifier('actual_features')), build.block([
                     build.function('error', [
                         build.string('Dependency'),
-                        build.string(_dependency_name(dep.package, dep.api)),
+                        build.string(_dependency_name(dep.package, api)),
                         build.string('previously configured with features'),
                         build.identifier('actual_features'),
                         build.string('but need'),
@@ -422,7 +424,7 @@ def _create_lib(self, pkg: PackageState, build: builder.Builder, crate_type: raw
             dep = pkg.manifest.dependencies[name]
             dependencies.append(build.identifier(_dependency_varname(dep.package)))
             if name != dep.package:
-                dep_pkg = self._dep_package(dep)
+                dep_pkg = self._dep_package(pkg, dep)
                 dep_lib_name = dep_pkg.manifest.lib.name
                 dependency_map[build.string(fixup_meson_varname(dep_lib_name))] = build.string(name)
         for name, sys_dep in pkg.manifest.system_dependencies.items():