dependencies: defer importing a custom dependency until it is used

This lessens the amount of code imported at Meson startup by mapping
each dependency to a dictionary entry and using a programmable import to
dynamically return it.

Minus 16 files and 6399 lines of code imported at startup.

1 files changed, 1 insertions, 1 deletions

diff --git a/run_project_tests.py b/run_project_tests.py
index bf8860862..facf1e98f 100755
--- a/run_project_tests.py
+++ b/run_project_tests.py
@@ -540,7 +540,7 @@ def validate_output(test: TestDef, stdo: str, stde: str) -> str:
 # coded to run as a batch process.
 def clear_internal_caches() -> None:
     import mesonbuild.interpreterbase
-    from mesonbuild.dependencies import CMakeDependency
+    from mesonbuild.dependencies.cmake import CMakeDependency
     from mesonbuild.mesonlib import PerMachine
     mesonbuild.interpreterbase.FeatureNew.feature_registry = {}
     CMakeDependency.class_cmakeinfo = PerMachine(None, None)