From 836a94d705c40bdbb1e944d091ff3adb29adfe49 Mon Sep 17 00:00:00 2001
From: Brian Flad <bflad417@gmail.com>
Date: Tue, 5 Oct 2021 16:20:19 -0400
Subject: [PATCH] types: Prevent panic with uninitialized Number Value (#200)

Reference: https://github.com/hashicorp/terraform-plugin-framework/issues/89
Reference: https://github.com/hashicorp/terraform-plugin-go/pull/114

This change will ensure that if the `Number` `Value` pointer is `nil`, that the returned value is an untyped `nil`, rather than a `*big.Float` typed `nil`.

The upstream `(tftypes.Value).IsNull()` method can only detect untyped `nil` for values. A related fix for `tftypes.NewValue()` to convert a `*big.Float` `nil` value into an untyped `nil` has also been merged upstream to fix this in depth.

Previously, this new test case would pass:

```go
		"value-nil": {
			input:       Number{Value: nil},
			expectation: (*big.Float)(nil),
		},
```

Now it appropriately expects:

```go
		"value-nil": {
			input:       Number{Value: nil},
			expectation: nil,
		},
```
---
 .changelog/200.txt   | 3 +++
 types/number.go      | 3 +++
 types/number_test.go | 4 ++++
 3 files changed, 10 insertions(+)
 create mode 100644 .changelog/200.txt

diff --git a/.changelog/200.txt b/.changelog/200.txt
new file mode 100644
index 000000000..b95a09621
--- /dev/null
+++ b/.changelog/200.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+types: Prevent panic with uninitialized `Number` `Value`
+```
diff --git a/types/number.go b/types/number.go
index f342c1da9..c47e1d24e 100644
--- a/types/number.go
+++ b/types/number.go
@@ -55,6 +55,9 @@ func (n Number) ToTerraformValue(_ context.Context) (interface{}, error) {
 	if n.Unknown {
 		return tftypes.UnknownValue, nil
 	}
+	if n.Value == nil {
+		return nil, nil
+	}
 	return n.Value, nil
 }
 
diff --git a/types/number_test.go b/types/number_test.go
index f30b1617f..5dac7ed4e 100644
--- a/types/number_test.go
+++ b/types/number_test.go
@@ -92,6 +92,10 @@ func TestNumberToTerraformValue(t *testing.T) {
 			input:       Number{Value: big.NewFloat(123)},
 			expectation: big.NewFloat(123),
 		},
+		"value-nil": {
+			input:       Number{Value: nil},
+			expectation: nil,
+		},
 		"unknown": {
 			input:       Number{Unknown: true},
 			expectation: tftypes.UnknownValue,