util-macros: ensure url_for_version works for older versions (spack#4…

…4421)

* util-macros: ensure url_for_version only used for older versions
* util-macros: use url.substitute_version after xz -> bz2
* util-macros: mv url_for_version down the file

var/spack/repos/builtin/packages/util-macros/package.py

@@ -14,11 +14,6 @@ class UtilMacros(AutotoolsPackage, XorgPackage):
     homepage = "https://gitlab.freedesktop.org/xorg/util/macros"
     xorg_mirror_path = "util/util-macros-1.19.1.tar.xz"
 
-    # note: url_for_version can only return a single url, no mirrors
-    def url_for_version(self, version):
-        if self.spec.satisfies("@:1.19"):
-            return self.urls[0].replace("xz", "bz2")
-
     maintainers("robert-mijakovic", "wdconinc")
 
     license("MIT")
@@ -29,6 +24,11 @@ def url_for_version(self, version):
     version("1.19.1", sha256="18d459400558f4ea99527bc9786c033965a3db45bf4c6a32eefdc07aa9e306a6")
     version("1.19.0", sha256="2835b11829ee634e19fa56517b4cfc52ef39acea0cd82e15f68096e27cbed0ba")
 
+    # note: url_for_version can only return a single url, no mirrors
+    def url_for_version(self, version):
+        if self.spec.satisfies("@:1.19"):
+            return spack.url.substitute_version(self.urls[0].replace("xz", "bz2"), version)
+
     def setup_dependent_build_environment(self, env, dependent_spec):
         """Adds the ACLOCAL path for autotools."""
         env.append_path("ACLOCAL_PATH", self.prefix.share.aclocal)