mesh-config compare: leave out merged or closed pull requests' candidates and a module with no manifest and no mirrored keys, so compare can come out empty (issue 1953 L5d, L5e)

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL

modules/mesh-config/cmd/mesh-config/takeover.go

@@ -350,6 +350,17 @@ func (c *Config) compare() (*Comparison, error) {
 	c.mirrorDeclarations(&mirror)
 	var diffs []Difference
 
+	// A placed module no catalog manifest names (mesh-wireguard, which the mesh ships computed) whose mirror key holds
+	// no config key declares nothing on both sides: nothing resolves from it, so nothing differs (issue 1953, L5d).
+	declaresNothing := map[string]bool{}
+	for module, d := range mirror.Declared {
+		if len(d.Config) == 0 {
+			if _, err := c.trunkDeclarations(module); err != nil {
+				declaresNothing[module] = true
+			}
+		}
+	}
+
 	// Each placed module's declarations: `declared` against the mirror's key for it.
 	for _, module := range modulesOf(own.Assignments) {
 		var ownRaw []byte
@@ -364,6 +375,7 @@ func (c *Config) compare() (*Comparison, error) {
 			mirrorRaw, _ = json.Marshal(normal(d.Config))
 		}
 		switch {
+		case ownRaw == nil && declaresNothing[module]:
 		case ownRaw == nil && mirrorRaw == nil:
 			diffs = append(diffs, Difference{What: DiffDeclared, Module: module, Why: "neither side holds its declarations"})
 		case ownRaw == nil:
@@ -412,9 +424,13 @@ func (c *Config) compare() (*Comparison, error) {
 	if cerr != nil {
 		diffs = append(diffs, Difference{What: DiffPull, Why: "the indexer's config candidates cannot be read: " + cerr.Error()})
 	}
+	settled := map[string]string{} // a pull request the forge says is no longer open → how it ended
 	for _, k := range unionKeys(cands, own.Pulls) {
 		a, aok := cands[k]
 		b, bok := own.Pulls[k]
+		if c.pullSettled(firstNonEmpty(a.Pull, b.Pull), settled) {
+			continue // a merged or closed pull request is no candidate to agree on (the operator, 2026-11-01)
+		}
 		switch {
 		case !aok:
 			diffs = append(diffs, Difference{What: DiffPull, Pull: b.Pull, Why: "the controller told its declarations and the indexer holds no candidate"})
@@ -456,6 +472,9 @@ func (c *Config) compare() (*Comparison, error) {
 		diffs = append(diffs, Difference{What: DiffValue, Node: u.Node, Module: u.Module, Why: "not resolved from the mirror: " + u.Why})
 	}
 	for _, u := range own.Unresolved {
+		if declaresNothing[u.Module] {
+			continue
+		}
 		diffs = append(diffs, Difference{What: DiffValue, Node: u.Node, Module: u.Module, Why: "not resolved from its own source: " + u.Why})
 	}
 	sort.SliceStable(diffs, func(i, j int) bool {
@@ -474,6 +493,41 @@ func (c *Config) compare() (*Comparison, error) {
 	return cmp, nil
 }
 
+func firstNonEmpty(a, b string) string {
+	if a != "" {
+		return a
+	}
+	return b
+}
+
+// pullSettled is whether the forge says a pull request merged or closed. Without a forge, or when it does not say, the
+// pull request counts as open, so its row stays (failure is loud).
+func (c *Config) pullSettled(pull string, memo map[string]string) bool {
+	if c.Forge == nil || pull == "" {
+		return false
+	}
+	if v, ok := memo[pull]; ok {
+		return v != ""
+	}
+	owner, repo, n, err := parsePull(pull)
+	if err != nil {
+		return false
+	}
+	open, merged, _, err := c.Forge.Pull(owner, repo, n)
+	switch {
+	case err != nil:
+		c.logf("[mesh-config] compare: the forge does not say whether %s is open (%v); its row stays", pull, err)
+		memo[pull] = ""
+	case open:
+		memo[pull] = ""
+	case merged:
+		memo[pull] = "merged"
+	default:
+		memo[pull] = "closed"
+	}
+	return memo[pull] != ""
+}
+
 // normal is declarations in one encoding: a null default as none.
 func normal(d map[string]Declaration) map[string]Declaration {
 	out := map[string]Declaration{}

modules/mesh-config/cmd/mesh-config/takeover_test.go

@@ -88,9 +88,18 @@ func TestCompareListsEveryDifferenceAndTheTakeOverWaitsForNone(t *testing.T) {
 		{"a pull request only the indexer holds", func(t *testing.T, m *memStore) {
 			candidate(t, m, "novox/mesh-catalog#9", "h1", `{"dunst":{"gap":{"kind":"","type":"number","default":2}}}`)
 		}, []string{"pull:novox/mesh-catalog#9"}},
+		{"a candidate of a merged pull request is no difference", func(t *testing.T, m *memStore) {
+			candidate(t, m, "novox/mesh-catalog#11", "h1", `{"dunst":{"gap":{"kind":"","type":"number","default":2}}}`)
+			candidate(t, m, "novox/mesh-catalog#10", "h2", `{"dunst":{"gap":{"kind":"","type":"number","default":2}}}`)
+		}, []string{"pull:novox/mesh-catalog#10"}},
+		{"a module no manifest names and the mirror declares nothing of", func(t *testing.T, m *memStore) {
+			m.assign(t, "g14", "mesh-wireguard")
+			m.mirror(t, MirrorDeclaredRead, "mesh-wireguard", `{"module":"mesh-wireguard","settings":{}}`)
+		}, nil},
 	}
 	for _, tc := range cases {
 		c, m, r := anAgreeingMesh(t)
+		c.Forge = &standForge{state: map[string][2]bool{"novox/mesh-catalog#11": {false, true}}}
 		tc.change(t, m)
 		cmp, err := c.Compare()
 		if err != nil {