From 2239fb253d5225b38209e1b1f929f1e00806a047 Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Tue, 3 Nov 2026 14:02:01 +0100
Subject: [PATCH] =?UTF-8?q?Rows=20for=20the=20composer's=20composition=20o?=
 =?UTF-8?q?f=20today:=20the=20same=20inputs=20give=20the=20running=20diges?=
 =?UTF-8?q?t,=20a=20changed=20input=20another,=20a=20build=20it=20cannot?=
 =?UTF-8?q?=20compose=20none=20(ADR=200601=20=C2=A71;=20review=20round=201?=
 =?UTF-8?q?,=20finding=202)?=
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---
 internal/selfcompose/selfcompose_test.go | 25 ++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/internal/selfcompose/selfcompose_test.go b/internal/selfcompose/selfcompose_test.go
index a9e663a..170a0b3 100644
--- a/internal/selfcompose/selfcompose_test.go
+++ b/internal/selfcompose/selfcompose_test.go
@@ -268,6 +268,31 @@ func TestTheNodeComposesItsWantsFromTheBus(t *testing.T) {
 		b.mu.Unlock()
 		t.Fatalf("handed %v, want %s and %s", got, lemursKey, nodeKey)
 	}
+	// ADR 0601 §1: the module composed today at the build it runs, as the agent compares it with what runs. The same inputs give
+	// the digest handed; a changed input (here its manifest's service, as a changed setting would change a file) another; a
+	// build that cannot be composed (no done build or manifest of it: held) gives none.
+	c.mu.Lock()
+	handedDig := c.handed[lemursKey]
+	c.mu.Unlock()
+	if dig, ok := c.ComposedToday(ctx, "lemurs", fp); !ok || dig != handedDig {
+		t.Errorf("composed today at the build it runs: %s %v, want %s", dig, ok, handedDig)
+	}
+	if dig, ok := c.ComposedToday(ctx, "lemurs", delivery.SourcePrefix2+strings.Repeat("9", 64)); ok {
+		t.Errorf("a build that cannot be composed was composed today: %s", dig)
+	}
+	chgJSON := strings.Replace(lemurs, `"state":"running"`, `"state":"stopped"`, 1)
+	chgDigest := delivery.ManifestDigest([]byte(chgJSON))
+	chgMan, _ := delivery.EncodeManifest(delivery.Manifest{Module: "lemurs", JSON: chgJSON})
+	chgKey, _ := delivery.ManifestsKey(chgDigest)
+	b.mu.Lock()
+	b.kv[delivery.ManifestsBucket+"/"+chgKey] = chgMan
+	b.mu.Unlock()
+	chgMod, _ := delivery.EncodeModule(delivery.Module{FP2: fp, Manifest: chgDigest, Repository: "novox/x", Commit: "c"})
+	c.takeModule(agent.Update{Key: "lemurs", Value: chgMod})
+	if dig, ok := c.ComposedToday(ctx, "lemurs", fp); !ok || dig == handedDig {
+		t.Errorf("composed today with a changed input: %s %v, want another digest than %s", dig, ok, handedDig)
+	}
+	c.takeModule(agent.Update{Key: "lemurs", Value: mod})
 
 	// Issue 1126, the switch made safe: a bus not answering for a moment (a reload of its accounts) is tried again and
 	// refuses nothing; a pass whose run ended refuses nothing either.