Add static-only option for ESMF (#34576)

var/spack/repos/builtin/packages/esmf/package.py

@@ -89,6 +89,7 @@ class Esmf(MakefilePackage):
         when="@8.3.0b09",
     )
     variant("debug", default=False, description="Make a debuggable version of the library")
+    variant("shared", default=True, description="Build shared library")
 
     # Required dependencies
     depends_on("zlib")
@@ -358,6 +359,10 @@ def edit(self, spec, prefix):
             # ESMF_XERCES_INCLUDE
             # ESMF_XERCES_LIBPATH
 
+        # Static-only option:
+        if "~shared" in spec:
+            os.environ["ESMF_SHARED_LIB_BUILD"] = "OFF"
+
     @run_after("install")
     def install_findesmf(self):
         install_tree("cmake", self.prefix.cmake)