dependencies: make the preferred LibType available to any ExternalDependency

Just like we automatically provide some reusable glue for self.static,
provide it here too. It seems plausibly like something people would
commonly want.

mesonbuild/dependencies/base.py

@@ -22,7 +22,7 @@ from enum import Enum
 
 from .. import mlog
 from ..compilers import clib_langs
-from ..mesonlib import MachineChoice, MesonException, HoldableObject
+from ..mesonlib import LibType, MachineChoice, MesonException, HoldableObject
 from ..mesonlib import version_compare_many
 from ..interpreterbase import FeatureDeprecated
 
@@ -319,6 +319,7 @@ class ExternalDependency(Dependency, HasNativeKwarg):
         self.required = kwargs.get('required', True)
         self.silent = kwargs.get('silent', False)
         self.static = kwargs.get('static', False)
+        self.libtype = LibType.STATIC if self.static else LibType.PREFER_SHARED
         if not isinstance(self.static, bool):
             raise DependencyException('Static keyword must be boolean')
         # Is this dependency to be run on the build platform?

mesonbuild/dependencies/pkgconfig.py

@@ -13,7 +13,7 @@
 # limitations under the License.
 
 from .base import ExternalDependency, DependencyException, sort_libpaths, DependencyTypeName
-from ..mesonlib import LibType, MachineChoice, OptionKey, OrderedSet, PerMachine, Popen_safe
+from ..mesonlib import MachineChoice, OptionKey, OrderedSet, PerMachine, Popen_safe
 from ..programs import find_external_program, ExternalProgram
 from .. import mlog
 from pathlib import PurePath
@@ -267,7 +267,6 @@ class PkgConfigDependency(ExternalDependency):
         libs_found: OrderedSet[str] = OrderedSet()
         # Track not-found libraries to know whether to add library paths
         libs_notfound = []
-        libtype = LibType.STATIC if self.static else LibType.PREFER_SHARED
         # Generate link arguments for this library
         link_args = []
         for lib in full_args:
@@ -283,7 +282,7 @@ class PkgConfigDependency(ExternalDependency):
                     continue
                 if self.clib_compiler:
                     args = self.clib_compiler.find_library(lib[2:], self.env,
-                                                           libpaths, libtype)
+                                                           libpaths, self.libtype)
                 # If the project only uses a non-clib language such as D, Rust,
                 # C#, Python, etc, all we can do is limp along by adding the
                 # arguments as-is and then adding the libpaths at the end.