From ca2472598826dba8c47d0490a41a1f25eb6b592f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bastian=20M=C3=BCller?= <bastian@turbolent.com>
Date: Fri, 14 Feb 2025 13:38:13 -0800
Subject: [PATCH 1/2] panic with UnreachableError in unreachable cases

---
 array.go                           | 2 +-
 cmd/smoke/array.go                 | 6 +++---
 cmd/smoke/map.go                   | 4 ++--
 cmd/smoke/typeinfo.go              | 2 +-
 map.go                             | 2 +-
 test_utils/expected_value_utils.go | 6 +++---
 6 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/array.go b/array.go
index 3d54976..57e421b 100644
--- a/array.go
+++ b/array.go
@@ -939,7 +939,7 @@ func (a *Array) Storable(_ SlabStorage, _ Address, maxInlineSize uint64) (Storab
 		return SlabIDStorable(a.SlabID()), nil
 
 	default:
-		panic("not reachable")
+		panic(NewUnreachableError())
 	}
 }
 
diff --git a/cmd/smoke/array.go b/cmd/smoke/array.go
index 9c58d88..d910a52 100644
--- a/cmd/smoke/array.go
+++ b/cmd/smoke/array.go
@@ -329,7 +329,7 @@ func modifyArray(
 		case arrayMutateChildContainerAfterAppend:
 			nextNestedLevels = nestedLevels - 1
 		default:
-			panic("not reachable")
+			panic(atree.NewUnreachableError())
 		}
 
 		// Create new chid child
@@ -366,7 +366,7 @@ func modifyArray(
 		case arrayMutateChildContainerAfterSet:
 			nextNestedLevels = nestedLevels - 1
 		default:
-			panic("not reachable")
+			panic(atree.NewUnreachableError())
 		}
 
 		// Create new child child
@@ -425,7 +425,7 @@ func modifyArray(
 		case arrayMutateChildContainerAfterInsert:
 			nextNestedLevels = nestedLevels - 1
 		default:
-			panic("not reachable")
+			panic(atree.NewUnreachableError())
 		}
 
 		// Create new child child
diff --git a/cmd/smoke/map.go b/cmd/smoke/map.go
index a049bbd..36d07a4 100644
--- a/cmd/smoke/map.go
+++ b/cmd/smoke/map.go
@@ -337,7 +337,7 @@ func modifyMap(
 		case mapMutateChildContainerAfterSet:
 			nextNestedLevels = nestedLevels - 1
 		default:
-			panic("not reachable")
+			panic(atree.NewUnreachableError())
 		}
 
 		var expectedKey, key atree.Value
@@ -416,7 +416,7 @@ func modifyMap(
 
 	case mapRemoveOp:
 		if m.Type().IsComposite() {
-			panic("not reachable")
+			panic(atree.NewUnreachableError())
 		}
 
 		// Use for-range on Go map to get random key
diff --git a/cmd/smoke/typeinfo.go b/cmd/smoke/typeinfo.go
index 343f7b5..0529aaf 100644
--- a/cmd/smoke/typeinfo.go
+++ b/cmd/smoke/typeinfo.go
@@ -125,7 +125,7 @@ func newCompositeTypeInfo() compositeTypeInfo {
 
 	endIndex := startIndex + count
 	if endIndex > len(compositeFieldNames) {
-		panic("not reachable")
+		panic(atree.NewUnreachableError())
 	}
 
 	return compositeTypeInfo{fieldStartIndex: startIndex, fieldEndIndex: endIndex}
diff --git a/map.go b/map.go
index dc867ed..a764fc9 100644
--- a/map.go
+++ b/map.go
@@ -1137,7 +1137,7 @@ func (m *OrderedMap) Storable(_ SlabStorage, _ Address, maxInlineSize uint64) (S
 		return SlabIDStorable(m.SlabID()), nil
 
 	default:
-		panic("not reachable")
+		panic(NewUnreachableError())
 	}
 }
 
diff --git a/test_utils/expected_value_utils.go b/test_utils/expected_value_utils.go
index 49d2a34..0cd4c91 100644
--- a/test_utils/expected_value_utils.go
+++ b/test_utils/expected_value_utils.go
@@ -32,7 +32,7 @@ type ExpectedArrayValue []atree.Value
 var _ atree.Value = &ExpectedArrayValue{}
 
 func (v ExpectedArrayValue) Storable(atree.SlabStorage, atree.Address, uint64) (atree.Storable, error) {
-	panic("not reachable")
+	panic(atree.NewUnreachableError())
 }
 
 // ExpectedMapValue
@@ -42,7 +42,7 @@ type ExpectedMapValue map[atree.Value]atree.Value
 var _ atree.Value = &ExpectedMapValue{}
 
 func (v ExpectedMapValue) Storable(atree.SlabStorage, atree.Address, uint64) (atree.Storable, error) {
-	panic("not reachable")
+	panic(atree.NewUnreachableError())
 }
 
 // ExpectedWrapperValue
@@ -58,7 +58,7 @@ func NewExpectedWrapperValue(value atree.Value) ExpectedWrapperValue {
 }
 
 func (v ExpectedWrapperValue) Storable(atree.SlabStorage, atree.Address, uint64) (atree.Storable, error) {
-	panic("not reachable")
+	panic(atree.NewUnreachableError())
 }
 
 func ValueEqual(expected atree.Value, actual atree.Value) (bool, error) {

From 827ac1ead3d2792adf7ca668017a324a947ebf7a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bastian=20M=C3=BCller?= <bastian@turbolent.com>
Date: Fri, 14 Feb 2025 13:39:10 -0800
Subject: [PATCH 2/2] write to stderr instead of panicing, like for other
 errors

---
 cmd/smoke/main.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cmd/smoke/main.go b/cmd/smoke/main.go
index 0a39891..1e46d33 100644
--- a/cmd/smoke/main.go
+++ b/cmd/smoke/main.go
@@ -117,7 +117,8 @@ func main() {
 		var err error
 		seed, err = strconv.ParseInt(strings.ReplaceAll(flagSeedHex, "0x", ""), 16, 64)
 		if err != nil {
-			panic("Failed to parse seed flag (hex string)")
+			fmt.Fprintf(os.Stderr, "failed to parse seed flag (hex string) %s: %s", flagSeedHex, err)
+			return
 		}
 	}