Add D&D enemy event artifact contract

internal/modules/dnd/codec/enemyevents/codec_test.go

@@ -0,0 +1,99 @@
+package enemyevents
+
+import (
+	"encoding/json"
+	"reflect"
+	"strings"
+	"testing"
+
+	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
+	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd"
+)
+
+func validList() dnd.EnemyEventList {
+	return dnd.EnemyEventList{Events: []dnd.EnemyEvent{
+		{Name: "Ashfang", Kind: dnd.EnemyEventKindEngaged, SourceRefs: refs(1, 2)},
+		{Name: "Ashfang", Kind: dnd.EnemyEventKindFled, SourceRefs: refs(5, 6)},
+	}}
+}
+
+func refs(start, end int) []source.SourceRef {
+	return []source.SourceRef{{SourceID: "session", StartUnitID: start, EndUnitID: end}}
+}
+
+func TestCodecRoundTripAndIdentity(t *testing.T) {
+	codec := New()
+	value := validList()
+	content, err := codec.Encode(value)
+	if err != nil {
+		t.Fatalf("Encode() error = %v", err)
+	}
+	decoded, err := codec.Decode(content)
+	if err != nil || !reflect.DeepEqual(decoded, value) {
+		t.Fatalf("Decode() = %#v, %v; want %#v", decoded, err, value)
+	}
+
+	schema := codec.Schema()
+	if codec.Kind() != dnd.EnemyEventListKind || codec.MediaType() != MediaType || schema.ID != SchemaID || schema.Name != SchemaName || schema.Version != SchemaVersion || !json.Valid(schema.JSONSchema) {
+		t.Fatalf("codec identity/schema = %q/%q %#v", codec.Kind(), codec.MediaType(), schema)
+	}
+	registry := pipeline.NewArtifactCodecRegistry()
+	if err := pipeline.RegisterArtifactCodec(registry, codec); err != nil {
+		t.Fatal(err)
+	}
+	spec, ok := registry.Spec(dnd.EnemyEventListKind)
+	if !ok || spec.SchemaDigest != contracts.DigestArtifactSchema(schema) {
+		t.Fatalf("registered spec = %#v, %t", spec, ok)
+	}
+}
+
+func TestCodecRejectsStrictJSONAndMissingRequiredFields(t *testing.T) {
+	validJSON := `{"events":[{"name":"Ashfang","kind":"engaged","source_refs":[{"source_id":"session","start_unit_id":1,"end_unit_id":1}]}]}`
+	tests := []struct {
+		name, raw, want string
+	}{
+		{"invalid JSON", `{`, "decode dnd enemy event list"},
+		{"unknown root field", `{"events":[],"unexpected":true}`, "unknown field"},
+		{"unknown event field", strings.Replace(validJSON, `"kind":"engaged"`, `"kind":"engaged","unexpected":true`, 1), "unknown field"},
+		{"missing events", `{}`, "events must be present"},
+		{"missing name", strings.Replace(validJSON, `"name":"Ashfang",`, "", 1), "events[0].name must be present"},
+		{"missing kind", strings.Replace(validJSON, `"kind":"engaged",`, "", 1), "events[0].kind must be present"},
+		{"missing refs", strings.Replace(validJSON, `,"source_refs":[{"source_id":"session","start_unit_id":1,"end_unit_id":1}]`, "", 1), "events[0].source_refs must be present"},
+		{"missing source ID", strings.Replace(validJSON, `"source_id":"session",`, "", 1), "source_refs[0].source_id must be present"},
+		{"trailing JSON", `{"events":[]} {}`, "multiple JSON values"},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			if _, err := New().Decode([]byte(test.raw)); err == nil || !strings.Contains(err.Error(), test.want) {
+				t.Fatalf("Decode() error = %v, want %q", err, test.want)
+			}
+		})
+	}
+}
+
+func TestCodecDefensivelyOwnsValuesAndDefersSemanticValidation(t *testing.T) {
+	codec := New()
+	candidate := dnd.EnemyEventList{Events: []dnd.EnemyEvent{{
+		Name: " ", Kind: "unsupported", SourceRefs: []source.SourceRef{{SourceID: "", StartUnitID: 0, EndUnitID: -1}},
+	}}}
+	content, err := codec.EncodeCandidate(candidate)
+	if err != nil {
+		t.Fatal(err)
+	}
+	decoded, err := codec.Decode(content)
+	if err != nil || !reflect.DeepEqual(decoded, candidate) {
+		t.Fatalf("Decode() = %#v, %v; want semantic candidate preservation", decoded, err)
+	}
+	decoded.Events[0].SourceRefs[0].SourceID = "changed"
+	if candidate.Events[0].SourceRefs[0].SourceID != "" {
+		t.Fatal("Decode() retained caller-owned source references")
+	}
+
+	first := codec.Schema()
+	first.JSONSchema[0] = '['
+	if second := codec.Schema(); !json.Valid(second.JSONSchema) || second.JSONSchema[0] == '[' {
+		t.Fatal("Schema() returned shared bytes")
+	}
+}