From e5aa440109f0464eb218aca93bb761b71d974c35 Mon Sep 17 00:00:00 2001
From: Morgan Bazalgette <morgan@morganbaz.com>
Date: Wed, 11 Oct 2023 00:16:12 +0100
Subject: [PATCH] fix(gnolang): allow floats in inc/dec statements

---
 gnovm/pkg/gnolang/op_inc_dec.go         | 47 +++++++++++++++++++++++--
 gnovm/tests/files/{inc.gno => inc0.gno} |  0
 gnovm/tests/files/inc1.gno              | 15 ++++++++
 3 files changed, 60 insertions(+), 2 deletions(-)
 rename gnovm/tests/files/{inc.gno => inc0.gno} (100%)
 create mode 100644 gnovm/tests/files/inc1.gno

diff --git a/gnovm/pkg/gnolang/op_inc_dec.go b/gnovm/pkg/gnolang/op_inc_dec.go
index 80987707035..70886497d5e 100644
--- a/gnovm/pkg/gnolang/op_inc_dec.go
+++ b/gnovm/pkg/gnolang/op_inc_dec.go
@@ -1,5 +1,12 @@
 package gnolang
 
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/cockroachdb/apd"
+)
+
 func (m *Machine) doOpInc() {
 	s := m.PopStmt().(*IncDecStmt)
 
@@ -42,8 +49,26 @@ func (m *Machine) doOpInc() {
 		lv.SetUint32(lv.GetUint32() + 1)
 	case Uint64Type:
 		lv.SetUint64(lv.GetUint64() + 1)
+	case Float32Type:
+		lv.SetFloat32(lv.GetFloat32() + 1)
+	case Float64Type:
+		lv.SetFloat64(lv.GetFloat64() + 1)
+	case BigintType, UntypedBigintType:
+		lb := lv.GetBigInt()
+		lb = big.NewInt(0).Add(lb, big.NewInt(1))
+		lv.V = BigintValue{V: lb}
+	case BigdecType, UntypedBigdecType:
+		lb := lv.GetBigDec()
+		sum := apd.New(0, 0)
+		cond, err := apd.BaseContext.WithPrecision(0).Add(sum, lb, apd.New(1, 0))
+		if err != nil {
+			panic(fmt.Sprintf("bigdec addition error: %v", err))
+		} else if cond.Inexact() {
+			panic(fmt.Sprintf("bigdec addition inexact: %v + 1", lb))
+		}
+		lv.V = BigdecValue{V: sum}
 	default:
-		panic("unexpected type in in operation")
+		panic(fmt.Sprintf("unexpected type %s in inc/dec operation", lv.T))
 	}
 
 	// Mark dirty in realm.
@@ -94,8 +119,26 @@ func (m *Machine) doOpDec() {
 		lv.SetUint32(lv.GetUint32() - 1)
 	case Uint64Type:
 		lv.SetUint64(lv.GetUint64() - 1)
+	case Float32Type:
+		lv.SetFloat32(lv.GetFloat32() - 1)
+	case Float64Type:
+		lv.SetFloat64(lv.GetFloat64() - 1)
+	case BigintType, UntypedBigintType:
+		lb := lv.GetBigInt()
+		lb = big.NewInt(0).Sub(lb, big.NewInt(1))
+		lv.V = BigintValue{V: lb}
+	case BigdecType, UntypedBigdecType:
+		lb := lv.GetBigDec()
+		sum := apd.New(0, 0)
+		cond, err := apd.BaseContext.WithPrecision(0).Sub(sum, lb, apd.New(1, 0))
+		if err != nil {
+			panic(fmt.Sprintf("bigdec addition error: %v", err))
+		} else if cond.Inexact() {
+			panic(fmt.Sprintf("bigdec addition inexact: %v + 1", lb))
+		}
+		lv.V = BigdecValue{V: sum}
 	default:
-		panic("unexpected type in in operation")
+		panic(fmt.Sprintf("unexpected type %s in inc/dec operation", lv.T))
 	}
 
 	// Mark dirty in realm.
diff --git a/gnovm/tests/files/inc.gno b/gnovm/tests/files/inc0.gno
similarity index 100%
rename from gnovm/tests/files/inc.gno
rename to gnovm/tests/files/inc0.gno
diff --git a/gnovm/tests/files/inc1.gno b/gnovm/tests/files/inc1.gno
new file mode 100644
index 00000000000..f997b3b9a00
--- /dev/null
+++ b/gnovm/tests/files/inc1.gno
@@ -0,0 +1,15 @@
+package main
+
+func main() {
+	var i float64 = 899
+	i++
+	println(i)
+
+	j := float32(901)
+	j--
+	println(j)
+}
+
+// Output:
+// 900
+// 900