Close out the D&D combat turn extraction roadmap

internal/modules/dnd/extract/combatturns/model_test.go

@@ -0,0 +1,58 @@
+package combatturns
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+func TestExtractionResponseDecodingPreservesValidatorOwnedSemantics(t *testing.T) {
+	content := []byte(`{"combat_turns":[{"actor":"","turn_kind":"unsupported","round":-1,"actions":[{"category":"unsupported","declaration":"","targets":[],"resolution":""}],"summary":"","source_refs":[{"start_unit_id":0,"end_unit_id":-1}]}]}`)
+	var response extractionResponse
+	if err := json.Unmarshal(content, &response); err != nil {
+		t.Fatalf("json.Unmarshal() error = %v, want semantic candidate", err)
+	}
+	turn := response.CombatTurns[0]
+	if turn.Round == nil || *turn.Round != -1 || turn.TurnKind != "unsupported" || turn.Actions[0].Category != "unsupported" || turn.Actions[0].Resolution == nil || *turn.Actions[0].Resolution != "" {
+		t.Fatalf("decoded turn = %#v, want validator-owned values preserved", turn)
+	}
+	if turn.SourceRefs[0] != (combatSourceRefResponse{StartUnitID: 0, EndUnitID: -1}) {
+		t.Fatalf("decoded source reference = %#v, want nonpositive values preserved", turn.SourceRefs[0])
+	}
+}
+
+func TestExtractionResponseDecodingDistinguishesMissingAndNullNullableFields(t *testing.T) {
+	validNulls := []byte(`{"combat_turns":[{"actor":"Aria","turn_kind":"turn","round":null,"actions":[{"category":"attack","declaration":"attacks","targets":[],"resolution":null}],"summary":"attacks","source_refs":[{"start_unit_id":1,"end_unit_id":1}]}]}`)
+	var response extractionResponse
+	if err := json.Unmarshal(validNulls, &response); err != nil {
+		t.Fatalf("json.Unmarshal(nulls) error = %v", err)
+	}
+	if response.CombatTurns[0].Round != nil || response.CombatTurns[0].Actions[0].Resolution != nil {
+		t.Fatalf("decoded nullables = %#v, want explicit null", response.CombatTurns[0])
+	}
+
+	for _, test := range []struct {
+		name    string
+		content string
+		field   string
+	}{
+		{
+			name:    "missing round",
+			content: `{"combat_turns":[{"actor":"Aria","turn_kind":"turn","actions":[],"summary":"attacks","source_refs":[]}]}`,
+			field:   "round",
+		},
+		{
+			name:    "missing resolution",
+			content: `{"combat_turns":[{"actor":"Aria","turn_kind":"turn","round":null,"actions":[{"category":"attack","declaration":"attacks","targets":[]}],"summary":"attacks","source_refs":[]}]}`,
+			field:   "resolution",
+		},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			var candidate extractionResponse
+			err := json.Unmarshal([]byte(test.content), &candidate)
+			if err == nil || !strings.Contains(err.Error(), test.field) {
+				t.Fatalf("json.Unmarshal() error = %v, want missing %s failure", err, test.field)
+			}
+		})
+	}
+}