Throw error when Tuple contains mixed Types

provider/validate.go

@@ -35,6 +35,68 @@ func (s *RawProviderServer) ValidateResourceTypeConfig(ctx context.Context, req
 		return resp, nil
 	}
 
+	// This section validates that all elements within a Tuple have the same Type.
+	// https://github.com/hashicorp/terraform-provider-kubernetes-alpha/issues/231
+	err = tftypes.Walk(config, func(path *tftypes.AttributePath, val tftypes.Value) (bool, error) {
+		if val.IsNull() || !val.IsKnown() {
+			return false, nil
+		}
+		if val.Type().Is(tftypes.Tuple{}) {
+			// Convert the Tuple into a Go value that can be inspected.
+			var tuple []tftypes.Value
+			val.As(&tuple)
+			containsObjects := false
+
+			// Inspect each Object in the Tuple.
+			for _, tupleElem := range tuple {
+				var objectAsMap map[string]tftypes.Value
+				if tupleElem.Type().Is(tftypes.Object{}) {
+					containsObjects = true
+					tupleElem.As(&objectAsMap)
+
+				}
+
+				// Collect the element types from the Object.
+				var elementTypes []tftypes.Value
+				for _, v := range objectAsMap {
+					elementTypes = append(elementTypes, v)
+				}
+
+				// Check the list of element types.
+				_, err := tftypes.TypeFromElements(elementTypes)
+				if err != nil {
+					resp.Diagnostics = append(resp.Diagnostics, &tfprotov5.Diagnostic{
+						Severity: tfprotov5.DiagnosticSeverityError,
+						Summary:  "Tuple element failed validation:" + tupleElem.String(),
+						Detail: err.Error(),
+					})
+					return false, err
+				}
+			}
+			// If a Tuple contains no Objects, its elements can be checked.
+			if !containsObjects {
+				_, err := tftypes.TypeFromElements(tuple)
+				if err != nil {
+					resp.Diagnostics = append(resp.Diagnostics, &tfprotov5.Diagnostic{
+						Severity: tfprotov5.DiagnosticSeverityError,
+						Summary:  "Tuple failed validation:" + val.String(),
+						Detail: err.Error(),
+					})
+					return false, err
+				}
+			}
+		}
+		return true, nil
+	})
+	if err != nil {
+		resp.Diagnostics = append(resp.Diagnostics, &tfprotov5.Diagnostic{
+			Severity: tfprotov5.DiagnosticSeverityError,
+			Summary:  "Config validation failed",
+			Detail:   err.Error(),
+		})
+		return resp, nil
+	}
+
 	att := tftypes.NewAttributePath()
 	att = att.WithAttributeName("manifest")