1 files changed, 130 insertions, 0 deletions
diff --git a/internal/validate/hardening_craft_validation_test.go b/internal/validate/hardening_craft_validation_test.go
new file mode 100644
index 0000000..5e5d83f
--- /dev/null
+++ b/internal/validate/hardening_craft_validation_test.go
@@ -0,0 +1,130 @@
+package validate
+
+import (
+	"path/filepath"
+	"testing"
+
+	"thehouseoficarus/internal/item"
+)
+
+// Regression: validateCraftBlocks must validate byproducts, the required tool,
+// and success/fail coherence. A typo in a byproduct previously passed startup
+// validation and the runtime wrote a phantom inventory slot with no item
+// definition; a tool that names no item was also unchecked; and a fail product
+// or fail_message on a recipe with no success formula can never be reached
+// (the engine hardcodes a 100% success chance).
+
+func writeCraftItem(t *testing.T, dir, name, body string) {
+	t.Helper()
+	writeFile(t, filepath.Join(dir, "items", name+".yaml"), body)
+}
+
+func TestCraftByproductMustExist(t *testing.T) {
+	dir := t.TempDir()
+	writeCraftItem(t, dir, "test_in", "id: test_in\nname: test in\n")
+	writeCraftItem(t, dir, "test_out", `id: test_out
+name: test out
+craft:
+  - type: crafting
+    ingredients:
+      - items: [test_in]
+        quantity: 1
+        byproducts: [missing_byproduct]
+`)
+	issues := validateCraftBlocks(newSource(dir))
+	if !containsMsg(issues, "nonexistent byproduct") {
+		t.Fatalf("expected nonexistent-byproduct error, got: %+v", issues)
+	}
+}
+
+func TestCraftToolMustExist(t *testing.T) {
+	dir := t.TempDir()
+	writeCraftItem(t, dir, "test_in", "id: test_in\nname: test in\n")
+	writeCraftItem(t, dir, "test_out", `id: test_out
+name: test out
+craft:
+  - type: crafting
+    tool: missing_tool
+    ingredients:
+      - items: [test_in]
+        quantity: 1
+`)
+	issues := validateCraftBlocks(newSource(dir))
+	if !containsMsg(issues, "nonexistent tool") {
+		t.Fatalf("expected nonexistent-tool error, got: %+v", issues)
+	}
+}
+
+func TestCraftFailWithoutSuccessFormulaIsWarned(t *testing.T) {
+	dir := t.TempDir()
+	writeCraftItem(t, dir, "test_in", "id: test_in\nname: test in\n")
+	writeCraftItem(t, dir, "burnt", "id: burnt\nname: burnt\n")
+	writeCraftItem(t, dir, "test_out", `id: test_out
+name: test out
+craft:
+  - type: cooking
+    fail: burnt
+    fail_message: You burn it.
+    ingredients:
+      - items: [test_in]
+        quantity: 1
+`)
+	issues := validateCraftBlocks(newSource(dir))
+	if !containsMsg(issues, "unreachable") {
+		t.Fatalf("expected unreachable fail warning, got: %+v", issues)
+	}
+	for _, issue := range issues {
+		if issue.Level == "ERROR" {
+			t.Fatalf("dead fail data must not fail startup validation: %+v", issue)
+		}
+	}
+}
+
+func TestCraftReachableFailProducesNoIssue(t *testing.T) {
+	dir := t.TempDir()
+	writeCraftItem(t, dir, "test_in", "id: test_in\nname: test in\n")
+	writeCraftItem(t, dir, "burnt", "id: burnt\nname: burnt\n")
+	writeCraftItem(t, dir, "test_out", `id: test_out
+name: test out
+craft:
+  - type: cooking
+    fail: burnt
+    fail_message: You burn it.
+    success:
+      base: 0.5
+      cap: 0.95
+      per_level: 0.02
+    ingredients:
+      - items: [test_in]
+        quantity: 1
+`)
+	if issues := validateCraftBlocks(newSource(dir)); len(issues) != 0 {
+		t.Fatalf("reachable fail branch must validate cleanly, got: %+v", issues)
+	}
+}
+
+func TestCraftFailureReachableFormula(t *testing.T) {
+	cases := []struct {
+		name   string
+		base   float64
+		perLvl float64
+		cap    float64
+		nilF   bool
+		want   bool
+	}{
+		{name: "no formula", nilF: true, want: false},
+		{name: "50% base", base: 0.5, perLvl: 0.02, cap: 0.95, want: true},
+		{name: "always succeeds", base: 1.0, perLvl: 0, cap: 1.0, want: false},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			craft := &item.CraftDef{Level: 1}
+			if !c.nilF {
+				craft.Success = &item.SuccessFormula{Base: c.base, PerLevel: c.perLvl, Cap: c.cap}
+			}
+			if got := craftFailureReachable(craft); got != c.want {
+				t.Errorf("craftFailureReachable = %v, want %v", got, c.want)
+			}
+		})
+	}
+}