Index sequence assembly and history lookups

internal/engine/compose_test.go

@@ -1,6 +1,7 @@
 package engine
 
 import (
+	"fmt"
 	"reflect"
 	"strings"
 	"testing"
@@ -8,6 +9,52 @@ import (
 	"gitea.maximumdirect.net/eric/ConfigKit/internal/document"
 )
 
+func TestComposeWideRegisteredCollectionsPreservesEvidenceAndReplay(t *testing.T) {
+	policy := sequencePolicy{identityFields: make(map[string]string)}
+	var inputs []*document.Node
+	for source := 0; source < 3; source++ {
+		var text strings.Builder
+		for collection := 0; collection < 128; collection++ {
+			key := fmt.Sprintf("records%d", collection)
+			policy.identityFields[Keys(key).String()] = "id"
+			fmt.Fprintf(&text, "%s: [{id: source%d}]\n", key, source)
+		}
+		inputs = append(inputs, parseCompositionDocument(t, fmt.Sprintf("source-%d", source), text.String()))
+	}
+	composed, diagnostics := composeDocumentsWithPolicy(policy, inputs...)
+	if len(diagnostics) != 0 {
+		t.Fatal(diagnostics)
+	}
+	working := &document.Node{Kind: document.Mapping}
+	for _, application := range composed.applications {
+		applyHistoryApplication(&working, application, new(mappingIndex))
+	}
+	if !configurationValuesEqual(working, composed.root) {
+		t.Fatal("wide registered collections replay differs from assembly")
+	}
+	for collection := 0; collection < 128; collection++ {
+		path := Keys(fmt.Sprintf("records%d", collection)).Index(2).Key("id")
+		origin := composed.origins[path.String()]
+		if len(origin.Locations) != 1 || origin.Locations[0].SourceID != "source-2" {
+			t.Fatalf("shifted origin at %s = %#v", path.String(), origin)
+		}
+		local, ok := historyApplicationLocalPath(composed.applications[2], path)
+		if !ok || local.String() != Keys(fmt.Sprintf("records%d", collection)).Index(0).Key("id").String() {
+			t.Fatal("wide local path projection failed")
+		}
+	}
+	clone := cloneComposedDocument(composed)
+	for _, original := range composed.applications[0].sequences {
+		pointer := original.path.String()
+		copy := clone.applications[0].sequencesByPath[pointer]
+		copy.path.segments[0].key = "changed"
+		if composed.applications[0].sequencesByPath[pointer].path.String() != pointer {
+			t.Fatal("history path index aliases cloned state")
+		}
+		break
+	}
+}
+
 func TestComposeDocumentsJoinsDisjointMappingsAndTracksClaims(t *testing.T) {
 	base := parseCompositionDocument(t, "source-1", `services:
   api: