patch-git: Support more Git trailers in patch-git (RHEL-173109)

The patch-git tool now ignores commonly used Git trailers (Acked-by,
Assisted-by, Reviewed-by, Reported-by, Signed-off-by, Suggested-by)
instead of rejecting them as unrecognized tags.

Resolves: RHEL-173109
Assisted-by: LLM
RPM-Changelog: -
RPM-Skip-Release: yes

patch-git.lua

@@ -1207,9 +1207,22 @@ do
       assert(not b and err == 'Branch must be zstream')
    end
 
+   -- Parser for ignored tags.
+   local function parse_ignore(tag, s)
+      return true
+   end
+
    -- These are the recognized trailer tags in Git commit messages.
    -- (Git calls them keys, see git-interpret-trailers(1).)
    local recognized_trailer_tags = {
+      ['Acked-By']={parse=parse_ignore, duplicates=true},
+      ['Assisted-By']={parse=parse_ignore, duplicates=true},
+      ['Co-Authored-By']={parse=parse_ignore, duplicates=true},
+      ['Reviewed-By']={parse=parse_ignore, duplicates=true},
+      ['Reported-By']={parse=parse_ignore, duplicates=true},
+      ['Signed-Off-By']={parse=parse_ignore, duplicates=true},
+      ['Suggested-By']={parse=parse_ignore, duplicates=true},
+      ['Tested-By']={parse=parse_ignore, duplicates=true},
       ['Resolves']={field='tickets',
                     parse=parse_ticket_string,
                     duplicates=true},
@@ -1234,6 +1247,20 @@ do
       end
    end
 
+   -- Automatically support lower-cased "-by" variants of dev-attribution tags.
+   do
+      local aliases = {}
+      for k, v in pairs(recognized_trailer_tags) do
+         if string.sub(k, -3) == '-By' then
+            aliases[string.sub(k, 1, 1) .. string.lower(string.sub(k, 2))] = v
+         end
+      end
+      -- Second loop to avoid structural mutation while iterating.
+      for k, v in pairs(aliases) do
+         recognized_trailer_tags[k] = v
+      end
+   end
+
    function parse_trailer(message)
       -- This holds due to the format of the input file.
       assert(string.sub(message, #message) == '\n')
@@ -1467,6 +1494,65 @@ RPM-Release: no
 ]])
       assert(not t)
       assert(err == 'malformed line in Git trailer after Resolves tag')
+
+      -- Ignored trailers.
+      t, err = parse_trailer([[Fix memory leak after fdopen seek failure
+
+- Backport: Remove memory leak in fdopen (bug 31840)
+
+Resolves: RHEL-108475
+Signed-Off-By: Signed Off <signedoff@example.com>
+Acked-by: Acked By <acked@example.com>
+Assisted-by: Assisted By <assisted@example.com>
+Co-authored-by: Co Authored <coauthored@example.com>
+Reviewed-by: Reviewed By <reviewed@example.com>
+Reviewed-By: Another Reviewed By <anotherreviewed@example.com>
+Reported-by: Reported By <reported@example.com>
+Suggested-by: Suggested By <suggested@example.com>
+Tested-by: Tested By <tested@example.com>
+Signed-off-by: Another Signed Off <anothersignedoff@example.com>
+]])
+      assert(t, err)
+      assert(t.tickets)
+      assert(#t.tickets == 1)
+      assert(t.tickets[1] == 'RHEL-108475')
+      assert(t.signed_off_by == true)
+      assert(t.acked_by == true)
+      assert(t.assisted_by == true)
+      assert(t.co_authored_by == true)
+      assert(t.reviewed_by == true)
+      assert(t.reported_by == true)
+      assert(t.suggested_by == true)
+      assert(t.tested_by == true)
+
+      -- Lowercase/incorrect casing for other tags is rejected.
+      t, err = parse_trailer([[Fix memory leak after fdopen seek failure
+
+resolves: RHEL-108475
+]])
+      assert(not t)
+      assert(err == 'not a recognized Git trailer tag: resolves')
+
+      t, err = parse_trailer([[Fix memory leak after fdopen seek failure
+
+acked-by: Acked By <acked@example.com>
+]])
+      assert(not t)
+      assert(err == 'not a recognized Git trailer tag: acked-by')
+
+      t, err = parse_trailer([[Fix memory leak after fdopen seek failure
+
+parent: 1234567890abcdef1234567890abcdef12345678
+]])
+      assert(not t)
+      assert(err == 'not a recognized Git trailer tag: parent')
+
+      t, err = parse_trailer([[Fix memory leak after fdopen seek failure
+
+Signed-off-By: Signed Off <signedoff@example.com>
+]])
+      assert(not t)
+      assert(err == 'not a recognized Git trailer tag: Signed-off-By')
    end
 end