Preserve inherited source origins and transfer evidence

internal/engine/inheritance_origin_test.go

@@ -0,0 +1,141 @@
+package engine
+
+import (
+	"io/fs"
+	"testing"
+	"testing/fstest"
+
+	"gitea.maximumdirect.net/eric/ConfigKit/internal/document"
+)
+
+func TestInheritedOriginsKeepSourcePathsPresenceAndIndependentReplacement(t *testing.T) {
+	parent := parseCompositionDocument(t, "source-1", `parent:
+  enabled: false
+  count: 0
+  optional: null
+  items: [{file: message.txt}]
+  settings: {shared: parent}
+`)
+	child := parseCompositionDocument(t, "source-2", `child:
+  extends: parent
+  count: 3
+  settings: {own: child}
+`)
+	composed, diagnostics := composeDocuments(parent, child)
+	if len(diagnostics) != 0 {
+		t.Fatal(diagnostics)
+	}
+	result, diagnostics := expandInheritanceWithOrigins(composed.root, composed.origins, defaultProjectionLimits())
+	if len(diagnostics) != 0 {
+		t.Fatal(diagnostics)
+	}
+	for _, key := range []string{"enabled", "optional"} {
+		path := Keys("child", key)
+		value, found := documentAtPath(result.root, path)
+		origin, hasOrigin := result.origins[path.String()]
+		if !found || !hasOrigin || value == nil || len(origin.Locations) != 1 || origin.Locations[0].SourceID != "source-1" ||
+			len(projectInheritanceSteps(origin)) != 1 {
+			t.Fatalf("inherited %s = %#v, %#v", key, value, origin)
+		}
+	}
+	count := result.origins["/child/count"]
+	if len(count.Locations) != 1 || count.Locations[0].SourceID != "source-2" || len(projectInheritanceSteps(count)) != 0 {
+		t.Fatalf("direct replacement origin = %#v", count)
+	}
+	if len(result.replacements) != 1 || result.replacements[0].path.String() != "/child/count" ||
+		result.replacements[0].before.Text != "0" || result.replacements[0].after.Text != "3" ||
+		len(result.replacements[0].previous) != 1 ||
+		len(projectInheritanceSteps(result.replacements[0].previous[0].origin)) != 1 {
+		t.Fatalf("displaced inheritance = %#v", result.replacements)
+	}
+	settings := result.origins["/child/settings"]
+	if len(settings.Locations) != 2 || settings.Locations[0].SourceID != "source-1" ||
+		settings.Locations[1].SourceID != "source-2" || len(projectInheritanceSteps(settings)) != 1 {
+		t.Fatalf("composite mapping origin = %#v", settings)
+	}
+	if originContainedBy(result.origins["/child/enabled"], result.origins["/parent/enabled"]) ||
+		originContainedBy(result.origins["/parent/enabled"], result.origins["/child/enabled"]) {
+		t.Fatal("direct and inherited evidence collapsed despite matching source coordinates")
+	}
+	original := result.origins["/child/enabled"]
+	detached := cloneOrigin(original)
+	detached.Locations[0].SourceID = "changed"
+	detached.contributors[0].source.segments[0].key = "changed"
+	stepsCopy := projectInheritanceSteps(original)
+	stepsCopy[0].Locations[0].SourceID = "changed"
+	if original.Locations[0].SourceID != "source-1" ||
+		original.contributors[0].source.String() != "/parent/enabled" ||
+		projectInheritanceSteps(original)[0].Locations[0].SourceID != "source-2" {
+		t.Fatal("cloned origin or projected steps changed retained evidence")
+	}
+	resource := result.origins["/child/items/0/file"]
+	steps := projectInheritanceSteps(resource)
+	if len(steps) != 1 || steps[0].From.String() != "/parent/items/0/file" ||
+		steps[0].To.String() != "/child/items/0/file" || steps[0].Reference.String() != "/child/extends" ||
+		len(resource.Locations) != 1 || resource.Locations[0].SourceID != "source-1" {
+		t.Fatalf("sequence resource origin = %#v, steps = %#v", resource, steps)
+	}
+	contexts := map[string]fs.FS{
+		"source-1": fstest.MapFS{"message.txt": &fstest.MapFile{Data: []byte("from parent")}},
+		"source-2": fstest.MapFS{"message.txt": &fstest.MapFile{Data: []byte("from child")}},
+	}
+	data, err := fs.ReadFile(contexts[resource.Locations[0].SourceID], "message.txt")
+	if err != nil || string(data) != "from parent" {
+		t.Fatalf("inherited resource = %q, %v", data, err)
+	}
+}
+
+func TestInheritedOriginsRetainChainsAndNestedDestinations(t *testing.T) {
+	first := parseCompositionDocument(t, "source-1", `first:
+  enabled: false
+  settings:
+    primary: {value: original}
+    secondary: {extends: primary}
+`)
+	second := parseCompositionDocument(t, "source-2", `first: {other: present}
+middle: {extends: first}
+last:
+  extends: middle
+  settings:
+    primary: {value: replaced}
+`)
+	composed, diagnostics := composeDocuments(first, second)
+	if len(diagnostics) != 0 {
+		t.Fatal(diagnostics)
+	}
+	result, diagnostics := expandInheritanceWithOrigins(composed.root, composed.origins, defaultProjectionLimits())
+	if len(diagnostics) != 0 {
+		t.Fatal(diagnostics)
+	}
+	chain := projectInheritanceSteps(result.origins["/last/enabled"])
+	if len(chain) != 2 || chain[0].From.String() != "/first/enabled" ||
+		chain[0].To.String() != "/middle/enabled" || chain[1].From.String() != "/middle/enabled" ||
+		chain[1].To.String() != "/last/enabled" {
+		t.Fatalf("chain = %#v", chain)
+	}
+	composite := result.origins["/last"]
+	if len(composite.Locations) < 2 || len(composite.contributors) != len(composite.Locations) {
+		t.Fatalf("composite contributors = %#v", composite)
+	}
+	seenSources := make(map[string]bool)
+	for _, contributor := range composite.contributors {
+		seenSources[contributor.location.SourceID] = true
+	}
+	if !seenSources["source-1"] || !seenSources["source-2"] {
+		t.Fatalf("same-layer source contributors = %#v", composite.contributors)
+	}
+	nested := projectInheritanceSteps(result.origins["/last/settings/secondary/value"])
+	if len(nested) != 1 || nested[0].From.String() != "/last/settings/primary/value" ||
+		nested[0].To.String() != "/last/settings/secondary/value" {
+		t.Fatalf("destination-specific nested transfer = %#v", nested)
+	}
+	if got := result.origins["/last/settings/secondary/value"].Locations[0].SourceID; got != "source-2" {
+		t.Fatalf("nested replacement source = %q", got)
+	}
+	if original, found := documentAtPath(first, Keys("first", "settings", "primary", "value")); !found || original.Text != "original" {
+		t.Fatal("expansion changed its input")
+	}
+	if inherited, found := documentAtPath(result.root, Keys("last", "settings", "secondary", "value")); !found || inherited.Kind != document.String || inherited.Text != "replaced" {
+		t.Fatalf("nested inherited value = %#v, %v", inherited, found)
+	}
+}