path: Initial Path Expression Support

.changelog/396.txt

@@ -0,0 +1,11 @@
+```release-note:feature
+path: Introduced attribute path expressions
+```
+
+```release-note:enhancement
+tfsdk: Added `AttributePathExpression` field to `ModifyAttributePlanRequest` and `ValidateAttributeRequest` types
+```
+
+```release-note:enhancement
+tfsdk: Added `PathMatches` method to `Config`, `Plan`, and `State` types
+```

internal/fromtftypes/attribute_path_step.go

@@ -0,0 +1,35 @@
+package fromtftypes
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/hashicorp/terraform-plugin-framework/attr"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+// AttributePathStep returns the path.PathStep equivalent of a
+// tftypes.AttributePathStep. An error is returned instead of diag.Diagnostics
+// so callers can include appropriate logical context about when the error
+// occurred.
+func AttributePathStep(ctx context.Context, tfType tftypes.AttributePathStep, attrType attr.Type) (path.PathStep, error) {
+	switch tfType := tfType.(type) {
+	case tftypes.AttributeName:
+		return path.PathStepAttributeName(string(tfType)), nil
+	case tftypes.ElementKeyInt:
+		return path.PathStepElementKeyInt(int64(tfType)), nil
+	case tftypes.ElementKeyString:
+		return path.PathStepElementKeyString(string(tfType)), nil
+	case tftypes.ElementKeyValue:
+		attrValue, err := Value(ctx, tftypes.Value(tfType), attrType)
+
+		if err != nil {
+			return nil, fmt.Errorf("unable to create PathStepElementKeyValue from tftypes.Value: %w", err)
+		}
+
+		return path.PathStepElementKeyValue{Value: attrValue}, nil
+	default:
+		return nil, fmt.Errorf("unknown tftypes.AttributePathStep: %#v", tfType)
+	}
+}

internal/fromtftypes/attribute_path_step_test.go

@@ -0,0 +1,83 @@
+package fromtftypes_test
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/hashicorp/terraform-plugin-framework/attr"
+	"github.com/hashicorp/terraform-plugin-framework/internal/fromtftypes"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+func TestAttributePathStep(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		tfType        tftypes.AttributePathStep
+		attrType      attr.Type
+		expected      path.PathStep
+		expectedError error
+	}{
+		"nil": {
+			tfType:        nil,
+			expected:      nil,
+			expectedError: fmt.Errorf("unknown tftypes.AttributePathStep: <nil>"),
+		},
+		"PathStepAttributeName": {
+			tfType:   tftypes.AttributeName("test"),
+			expected: path.PathStepAttributeName("test"),
+		},
+		"PathStepElementKeyInt": {
+			tfType:   tftypes.ElementKeyInt(1),
+			expected: path.PathStepElementKeyInt(1),
+		},
+		"PathStepElementKeyString": {
+			tfType:   tftypes.ElementKeyString("test"),
+			expected: path.PathStepElementKeyString("test"),
+		},
+		"PathStepElementKeyValue": {
+			tfType:   tftypes.ElementKeyValue(tftypes.NewValue(tftypes.String, "test")),
+			attrType: types.StringType,
+			expected: path.PathStepElementKeyValue{Value: types.String{Value: "test"}},
+		},
+		"PathStepElementKeyValue-error": {
+			tfType:        tftypes.ElementKeyValue(tftypes.NewValue(tftypes.String, "test")),
+			attrType:      types.BoolType,
+			expected:      nil,
+			expectedError: fmt.Errorf("unable to create PathStepElementKeyValue from tftypes.Value: unable to convert tftypes.Value (tftypes.String<\"test\">) to attr.Value: can't unmarshal tftypes.String into *bool, expected boolean"),
+		},
+	}
+
+	for name, testCase := range testCases {
+		name, testCase := name, testCase
+
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			got, err := fromtftypes.AttributePathStep(context.Background(), testCase.tfType, testCase.attrType)
+
+			if err != nil {
+				if testCase.expectedError == nil {
+					t.Fatalf("expected no error, got: %s", err)
+				}
+
+				if !strings.Contains(err.Error(), testCase.expectedError.Error()) {
+					t.Fatalf("expected error %q, got: %s", testCase.expectedError, err)
+				}
+			}
+
+			if err == nil && testCase.expectedError != nil {
+				t.Fatalf("got no error, tfType: %s", testCase.expectedError)
+			}
+
+			if diff := cmp.Diff(got, testCase.expected); diff != "" {
+				t.Errorf("unexpected difference: %s", diff)
+			}
+		})
+	}
+}

internal/fromtftypes/doc.go

@@ -0,0 +1,3 @@
+// Package fromtftypes contains functions to convert from terraform-plugin-go
+// tftypes types to framework types.
+package fromtftypes

internal/fromtftypes/value.go

@@ -0,0 +1,24 @@
+package fromtftypes
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/hashicorp/terraform-plugin-framework/attr"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+// Value returns the attr.Value equivalent to the tftypes.Value.
+func Value(ctx context.Context, tfType tftypes.Value, attrType attr.Type) (attr.Value, error) {
+	if attrType == nil {
+		return nil, fmt.Errorf("unable to convert tftypes.Value (%s) to attr.Value: missing attr.Type", tfType.String())
+	}
+
+	attrValue, err := attrType.ValueFromTerraform(ctx, tfType)
+
+	if err != nil {
+		return nil, fmt.Errorf("unable to convert tftypes.Value (%s) to attr.Value: %w", tfType.String(), err)
+	}
+
+	return attrValue, nil
+}