[PROPOSAL] Implement TypeSet resource.TestCheckFuncs (#13556)

* Implement TypeSet resource.TestCheckFuncs

* Add unit tests and rename pkg

Added check that the last part of a path is in fact the sentinel value

aws/internal/tfawsresource/testing.go

@@ -0,0 +1,120 @@
+package tfawsresource
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/terraform-plugin-sdk/helper/resource"
+	"github.com/hashicorp/terraform-plugin-sdk/terraform"
+)
+
+const (
+	sentinelIndex = "*"
+)
+
+// TestCheckTypeSetElemNestedAttrs is a resource.TestCheckFunc that accepts a resource
+// name, an attribute path, which should use the sentinel value '*' for indexing
+// into a TypeSet. The function verifies that an element matches the whole value
+// map.
+//
+// Use this function over SDK provided TestCheckFunctions when validating a
+// TypeSet where its elements are a nested object with their own attrs/values.
+//
+// Please note, if the provided value map is not granular enough, there exists
+// the possibility you match an element you were not intending to, in the TypeSet.
+// Provide a full mapping of attributes to be sure the unique element exists.
+func TestCheckTypeSetElemNestedAttrs(res, attr string, values map[string]string) resource.TestCheckFunc {
+	return func(s *terraform.State) error {
+		ms := s.RootModule()
+		rs, ok := ms.Resources[res]
+		if !ok {
+			return fmt.Errorf("Not found: %s in %s", res, ms.Path)
+		}
+
+		is := rs.Primary
+		if is == nil {
+			return fmt.Errorf("No primary instance: %s in %s", res, ms.Path)
+		}
+
+		matches := make(map[string]int)
+		attrParts := strings.Split(attr, ".")
+		if attrParts[len(attrParts)-1] != sentinelIndex {
+			return fmt.Errorf("%q does not end with the special value %q", attr, sentinelIndex)
+		}
+		for stateKey, stateValue := range is.Attributes {
+			stateKeyParts := strings.Split(stateKey, ".")
+			// a Set/List item with nested attrs would have a flatmap address of
+			// at least length 3
+			// foo.0.name = "bar"
+			if len(stateKeyParts) < 3 {
+				continue
+			}
+			var pathMatch bool
+			for i := range attrParts {
+				if attrParts[i] != stateKeyParts[i] && attrParts[i] != sentinelIndex {
+					break
+				}
+				if i == len(attrParts)-1 {
+					pathMatch = true
+				}
+			}
+			if !pathMatch {
+				continue
+			}
+			elementId := stateKeyParts[len(attrParts)-1]
+			nestedAttr := strings.Join(stateKeyParts[len(attrParts):], ".")
+			if v, keyExists := values[nestedAttr]; keyExists && v == stateValue {
+				matches[elementId] = matches[elementId] + 1
+				if matches[elementId] == len(values) {
+					return nil
+				}
+			}
+		}
+
+		return fmt.Errorf("%q no TypeSet element %q, with nested attrs %#v in state: %#v", res, attr, values, is.Attributes)
+	}
+}
+
+// TestCheckTypeSetElemAttr is a resource.TestCheckFunc that accepts a resource
+// name, an attribute path, which should use the sentinel value '*' for indexing
+// into a TypeSet. The function verifies that an element matches the provided
+// value.
+//
+// Use this function over SDK provided TestCheckFunctions when validating a
+// TypeSet where its elements are a simple value
+func TestCheckTypeSetElemAttr(res, attr, value string) resource.TestCheckFunc {
+	return func(s *terraform.State) error {
+		ms := s.RootModule()
+		rs, ok := ms.Resources[res]
+		if !ok {
+			return fmt.Errorf("Not found: %s in %s", res, ms.Path)
+		}
+
+		is := rs.Primary
+		if is == nil {
+			return fmt.Errorf("No primary instance: %s in %s", res, ms.Path)
+		}
+
+		attrParts := strings.Split(attr, ".")
+		if attrParts[len(attrParts)-1] != sentinelIndex {
+			return fmt.Errorf("%q does not end with the special value %q", attr, sentinelIndex)
+		}
+		for stateKey, stateValue := range is.Attributes {
+			if stateValue == value {
+				stateKeyParts := strings.Split(stateKey, ".")
+				if len(stateKeyParts) == len(attrParts) {
+					for i := range attrParts {
+						if attrParts[i] != stateKeyParts[i] && attrParts[i] != sentinelIndex {
+							break
+						}
+						if i == len(attrParts)-1 {
+							return nil
+						}
+					}
+				}
+			}
+		}
+
+		return fmt.Errorf("%q no TypeSet element %q, with value %q in state: %#v", res, attr, value, is.Attributes)
+	}
+}