Prevent installer from working with RobotPy versions from other years

robotpy_installer/pyproject.py

@@ -9,6 +9,7 @@
 import tomli
 import tomlkit
 
+from . import installer
 from . import pypackages
 from .pypackages import Packages, Env
 from .errors import Error
@@ -22,6 +23,10 @@ class NoRobotpyError(PyprojectError):
     pass
 
 
+class UnsupportedRobotpyVersion(PyprojectError):
+    pass
+
+
 def toml_path(project_path: pathlib.Path):
     return project_path / "pyproject.toml"
 
@@ -223,6 +228,14 @@ def _load(
             f"{pyproject_path}: tools.robotpy.robotpy_version is not a valid version"
         ) from None
 
+    supported_year = int(installer._WPILIB_YEAR)
+    if robotpy_version.major != supported_year:
+        msg = (
+            f"Only RobotPy {supported_year}.x is supported by this version "
+            f"of robotpy-installer ({pyproject_path} has {robotpy_version})"
+        )
+        raise UnsupportedRobotpyVersion(msg)
+
     robotpy_extras_any = robotpy_data.get("robotpy_extras")
     if isinstance(robotpy_extras_any, list):
         robotpy_extras = list(map(str, robotpy_extras_any))