From 77d6820075989b5de42bf278d02f58ba647a012d Mon Sep 17 00:00:00 2001
From: Pieter Noordhuis <pieter.noordhuis@databricks.com>
Date: Wed, 17 Apr 2024 10:58:07 +0200
Subject: [PATCH] Convert between integer and float in normalization (#1371)

## Changes

We currently issue a warning if an integer is used where a floating
point number is expected. But if they are convertible, we should convert
and not issue a warning. This change fixes normalization if they are
convertible between each other. We still produce a warning if the type
conversion leads to a loss in precision.

## Tests

Unit tests pass.
---
 libs/dyn/convert/normalize.go      | 20 +++++++++++++
 libs/dyn/convert/normalize_test.go | 46 ++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)

diff --git a/libs/dyn/convert/normalize.go b/libs/dyn/convert/normalize.go
index b4bee977..35d4d821 100644
--- a/libs/dyn/convert/normalize.go
+++ b/libs/dyn/convert/normalize.go
@@ -293,6 +293,16 @@ func (n normalizeOptions) normalizeInt(typ reflect.Type, src dyn.Value, path dyn
 	switch src.Kind() {
 	case dyn.KindInt:
 		out = src.MustInt()
+	case dyn.KindFloat:
+		out = int64(src.MustFloat())
+		if src.MustFloat() != float64(out) {
+			return dyn.InvalidValue, diags.Append(diag.Diagnostic{
+				Severity: diag.Warning,
+				Summary:  fmt.Sprintf(`cannot accurately represent "%g" as integer due to precision loss`, src.MustFloat()),
+				Location: src.Location(),
+				Path:     path,
+			})
+		}
 	case dyn.KindString:
 		var err error
 		out, err = strconv.ParseInt(src.MustString(), 10, 64)
@@ -326,6 +336,16 @@ func (n normalizeOptions) normalizeFloat(typ reflect.Type, src dyn.Value, path d
 	switch src.Kind() {
 	case dyn.KindFloat:
 		out = src.MustFloat()
+	case dyn.KindInt:
+		out = float64(src.MustInt())
+		if src.MustInt() != int64(out) {
+			return dyn.InvalidValue, diags.Append(diag.Diagnostic{
+				Severity: diag.Warning,
+				Summary:  fmt.Sprintf(`cannot accurately represent "%d" as floating point number due to precision loss`, src.MustInt()),
+				Location: src.Location(),
+				Path:     path,
+			})
+		}
 	case dyn.KindString:
 		var err error
 		out, err = strconv.ParseFloat(src.MustString(), 64)
diff --git a/libs/dyn/convert/normalize_test.go b/libs/dyn/convert/normalize_test.go
index 1a0869a9..843b4ea5 100644
--- a/libs/dyn/convert/normalize_test.go
+++ b/libs/dyn/convert/normalize_test.go
@@ -555,6 +555,27 @@ func TestNormalizeIntNil(t *testing.T) {
 	}, err[0])
 }
 
+func TestNormalizeIntFromFloat(t *testing.T) {
+	var typ int
+	vin := dyn.V(float64(1.0))
+	vout, err := Normalize(&typ, vin)
+	assert.Empty(t, err)
+	assert.Equal(t, dyn.V(int64(1)), vout)
+}
+
+func TestNormalizeIntFromFloatError(t *testing.T) {
+	var typ int
+	vin := dyn.V(1.5)
+	_, err := Normalize(&typ, vin)
+	assert.Len(t, err, 1)
+	assert.Equal(t, diag.Diagnostic{
+		Severity: diag.Warning,
+		Summary:  `cannot accurately represent "1.5" as integer due to precision loss`,
+		Location: vin.Location(),
+		Path:     dyn.EmptyPath,
+	}, err[0])
+}
+
 func TestNormalizeIntFromString(t *testing.T) {
 	var typ int
 	vin := dyn.V("123")
@@ -618,6 +639,31 @@ func TestNormalizeFloatNil(t *testing.T) {
 	}, err[0])
 }
 
+func TestNormalizeFloatFromInt(t *testing.T) {
+	var typ float64
+
+	// Maximum safe integer that can be accurately represented as a float.
+	vin := dyn.V(int64(9007199254740992))
+	vout, err := Normalize(&typ, vin)
+	assert.Empty(t, err)
+	assert.Equal(t, dyn.V(float64(9007199254740992)), vout)
+}
+
+func TestNormalizeFloatFromIntError(t *testing.T) {
+	var typ float64
+
+	// Minimum integer that cannot be accurately represented as a float.
+	vin := dyn.V(9007199254740992 + 1)
+	_, err := Normalize(&typ, vin)
+	assert.Len(t, err, 1)
+	assert.Equal(t, diag.Diagnostic{
+		Severity: diag.Warning,
+		Summary:  `cannot accurately represent "9007199254740993" as floating point number due to precision loss`,
+		Location: vin.Location(),
+		Path:     dyn.EmptyPath,
+	}, err[0])
+}
+
 func TestNormalizeFloatFromString(t *testing.T) {
 	var typ float64
 	vin := dyn.V("1.2")