forgeversion: make sure nothing is stored in distprefix

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2359090

rpm/macros.d/macros.forge

@@ -143,6 +143,12 @@ if util.get_flag("a") then
 else
   local i = util.get_flag("z", true) or ""
   part = part .. (util.get_macro("_forgeversionsuffix" .. i) or "")
+  -- Regardless of whether -a is used, undefine all other distprefixes to avoid
+  -- extra information in Release when forgeversion is already used.
+  -- See https://bugzilla.redhat.com/show_bug.cgi?id=2359090.
+  for i=0,9999 do
+    rpm.undefine("distprefix" .. i)
+  end
 end
 \
 -- Strip any leading '.'

tests/vectors.yaml

@@ -530,10 +530,16 @@ cases:
 
   - id: unit_forge_version
     defines:
+      # Check with version
       - version: "1.0.0"
         _forgeversionsuffix0: ".abcd"
         _forgeversionsuffix5: ".sxyz"
         _forgeversionsuffix9999: ".s456"
+        # Used for distprefix check
+        distprefix0: "something"
+        distprefix5: "something"
+        distprefix9999: "something"
+      # Check with version0
       - version0: "1.0.0"
         _forgeversionsuffix0: ".abcd"
         _forgeversionsuffix5: ".sxyz"
@@ -545,15 +551,19 @@ cases:
         _forgeversionsuffix5: ".sxyz"
         _forgeversionsuffix9999: ".s456"
     expected:
+      "forgeversion": "1.0.0^abcd"
+      # Make sure distprefix is cleared out
+      "undefined distprefix": "1"
+      "undefined distprefix0": "1"
+      "undefined distprefix5": "1"
+      "undefined distprefix9999": "1"
+      "forgeversion -z0": "1.0.0^abcd"
+      # Only first with pre-release
+      "forgeversion -p": "1.0.0~abcd"
       # Basic all usage
       "forgeversion -a": "1.0.0^abcd.sxyz.s456"
       # Pre-release
       "forgeversion -p -a": "1.0.0~abcd.sxyz.s456"
-      # Only first
-      "forgeversion": "1.0.0^abcd"
-      "forgeversion -z0": "1.0.0^abcd"
-      # Only first with pre-release
-      "forgeversion -p": "1.0.0~abcd"
       # -z12 doesn't exist
       "forgeversion -z12": "1.0.0"
       "forgeversion -p -z12": "1.0.0"
@@ -582,3 +592,5 @@ cases:
     zero_indexed: *zeroidx
     expected_undefined:
       - distprefix
+
+