Structured Plan Renderer: Add tests validating behaviour of dynamic types (#32482)

* add support for dynamic types into attribute processing

* fix names

* add tests

internal/command/jsonformat/differ/attribute.go

@@ -49,6 +49,12 @@ func (v Value) computeChangeForType(ctype cty.Type) change.Change {
 
 	switch {
 	case ctype == cty.NilType, ctype == cty.DynamicPseudoType:
+		// Forward nil or dynamic types over to be processed as outputs.
+		// There is nothing particularly special about the way outputs are
+		// processed that make this unsafe, we could just as easily call this
+		// function computeChangeForDynamicValues(), but external callers will
+		// only be in this situation when processing outputs so this function
+		// is named for their benefit.
 		return v.ComputeChangeForOutput()
 	case ctype.IsPrimitiveType():
 		return v.computeAttributeChangeAsPrimitive(ctype)

internal/command/jsonformat/differ/value_test.go

@@ -1573,6 +1573,33 @@ func TestValue_PrimitiveAttributes(t *testing.T) {
 			attribute:      cty.String,
 			validateChange: change.ValidatePrimitive(strptr("\"old\""), strptr("\"old\""), plans.NoOp, false),
 		},
+		"dynamic": {
+			input: Value{
+				Before: "old",
+				After:  "new",
+			},
+			attribute:      cty.DynamicPseudoType,
+			validateChange: change.ValidatePrimitive(strptr("\"old\""), strptr("\"new\""), plans.Update, false),
+			validateSliceChanges: []change.ValidateChangeFunc{
+				change.ValidatePrimitive(strptr("\"old\""), nil, plans.Delete, false),
+				change.ValidatePrimitive(nil, strptr("\"new\""), plans.Create, false),
+			},
+		},
+		"dynamic_type_change": {
+			input: Value{
+				Before: "old",
+				After:  4.0,
+			},
+			attribute: cty.DynamicPseudoType,
+			validateChange: change.ValidateTypeChange(
+				change.ValidatePrimitive(strptr("\"old\""), nil, plans.Delete, false),
+				change.ValidatePrimitive(nil, strptr("4"), plans.Create, false),
+				plans.Update, false),
+			validateSliceChanges: []change.ValidateChangeFunc{
+				change.ValidatePrimitive(strptr("\"old\""), nil, plans.Delete, false),
+				change.ValidatePrimitive(nil, strptr("4"), plans.Create, false),
+			},
+		},
 	}
 	for name, tmp := range tcs {
 		tc := tmp