all: Refactor schema validation to support type-specific logic and prevent AttributeTypes/ElementType field panics

.changes/unreleased/BUG FIXES-20230329-102850.yaml

@@ -0,0 +1,7 @@
+kind: BUG FIXES
+body: 'datasource/schema: Raise errors with `ListAttribute`, `MapAttribute`, `ObjectAttribute`,
+  and `SetAttribute` implementations instead of panics when missing required `AttributeTypes` or
+  `ElementTypes` fields'
+time: 2023-03-29T10:28:50.525346-04:00
+custom:
+  Issue: "699"

.changes/unreleased/BUG FIXES-20230329-102851.yaml

@@ -0,0 +1,7 @@
+kind: BUG FIXES
+body: 'provider/metaschema: Raise errors with `ListAttribute`, `MapAttribute`, `ObjectAttribute`,
+  and `SetAttribute` implementations instead of panics when missing required `AttributeTypes` or
+  `ElementTypes` fields'
+time: 2023-03-29T10:28:51.525346-04:00
+custom:
+  Issue: "699"

.changes/unreleased/BUG FIXES-20230329-102852.yaml

@@ -0,0 +1,7 @@
+kind: BUG FIXES
+body: 'provider/schema: Raise errors with `ListAttribute`, `MapAttribute`, `ObjectAttribute`,
+  and `SetAttribute` implementations instead of panics when missing required `AttributeTypes` or
+  `ElementTypes` fields'
+time: 2023-03-29T10:28:52.525346-04:00
+custom:
+  Issue: "699"

.changes/unreleased/BUG FIXES-20230329-102853.yaml

@@ -0,0 +1,7 @@
+kind: BUG FIXES
+body: 'resource/schema: Raise errors with `ListAttribute`, `MapAttribute`, `ObjectAttribute`,
+  and `SetAttribute` implementations instead of panics when missing required `AttributeTypes` or
+  `ElementTypes` fields'
+time: 2023-03-29T10:28:53.525346-04:00
+custom:
+  Issue: "699"

.changes/unreleased/ENHANCEMENTS-20230329-102106.yaml

@@ -0,0 +1,6 @@
+kind: ENHANCEMENTS
+body: 'datasource/schema: Added `Schema` type `ValidateImplementation()` method, which performs framework-defined
+  schema validation and can be used in unit testing'
+time: 2023-03-29T10:21:06.251285-04:00
+custom:
+  Issue: "699"

.changes/unreleased/ENHANCEMENTS-20230329-102107.yaml

@@ -0,0 +1,6 @@
+kind: ENHANCEMENTS
+body: 'provider/metaschema: Added `Schema` type `ValidateImplementation()` method, which performs framework-defined
+  schema validation and can be used in unit testing'
+time: 2023-03-29T10:21:07.251285-04:00
+custom:
+  Issue: "699"

.changes/unreleased/ENHANCEMENTS-20230329-102108.yaml

@@ -0,0 +1,6 @@
+kind: ENHANCEMENTS
+body: 'provider/schema: Added `Schema` type `ValidateImplementation()` method, which performs framework-defined
+  schema validation and can be used in unit testing'
+time: 2023-03-29T10:21:08.251285-04:00
+custom:
+  Issue: "699"

.changes/unreleased/ENHANCEMENTS-20230329-102109.yaml

@@ -0,0 +1,6 @@
+kind: ENHANCEMENTS
+body: 'resource/schema: Added `Schema` type `ValidateImplementation()` method, which performs framework-defined
+  schema validation and can be used in unit testing'
+time: 2023-03-29T10:21:09.251285-04:00
+custom:
+  Issue: "699"

.changes/unreleased/NOTES-20230329-124336.yaml

@@ -0,0 +1,6 @@
+kind: NOTES
+body: 'datasource/schema: The `Schema` type `Validate()` method has been deprecated
+  in preference of `ValidateImplementation()`'
+time: 2023-03-29T12:43:36.636825-04:00
+custom:
+  Issue: "699"

.changes/unreleased/NOTES-20230329-124337.yaml

@@ -0,0 +1,6 @@
+kind: NOTES
+body: 'provider/metaschema: The `Schema` type `Validate()` method has been deprecated
+  in preference of `ValidateImplementation()`'
+time: 2023-03-29T12:43:37.636825-04:00
+custom:
+  Issue: "699"

.changes/unreleased/NOTES-20230329-124338.yaml

@@ -0,0 +1,6 @@
+kind: NOTES
+body: 'provider/schema: The `Schema` type `Validate()` method has been deprecated
+  in preference of `ValidateImplementation()`'
+time: 2023-03-29T12:43:38.636825-04:00
+custom:
+  Issue: "699"

.changes/unreleased/NOTES-20230329-124339.yaml

@@ -0,0 +1,6 @@
+kind: NOTES
+body: 'resource/schema: The `Schema` type `Validate()` method has been deprecated
+  in preference of `ValidateImplementation()`'
+time: 2023-03-29T12:43:39.636825-04:00
+custom:
+  Issue: "699"

datasource/schema/list_attribute.go

@@ -1,6 +1,8 @@
 package schema
 
 import (
+	"context"
+
 	"github.com/hashicorp/terraform-plugin-framework/attr"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema/fwxschema"
@@ -12,8 +14,9 @@ import (
 
 // Ensure the implementation satisifies the desired interfaces.
 var (
-	_ Attribute                             = ListAttribute{}
-	_ fwxschema.AttributeWithListValidators = ListAttribute{}
+	_ Attribute                                    = ListAttribute{}
+	_ fwschema.AttributeWithValidateImplementation = ListAttribute{}
+	_ fwxschema.AttributeWithListValidators        = ListAttribute{}
 )
 
 // ListAttribute represents a schema attribute that is a list with a single
@@ -195,3 +198,13 @@ func (a ListAttribute) IsSensitive() bool {
 func (a ListAttribute) ListValidators() []validator.List {
 	return a.Validators
 }
+
+// ValidateImplementation contains logic for validating the
+// provider-defined implementation of the attribute to prevent unexpected
+// errors or panics. This logic runs during the GetProviderSchema RPC
+// and should never include false positives.
+func (a ListAttribute) ValidateImplementation(ctx context.Context, req fwschema.ValidateImplementationRequest, resp *fwschema.ValidateImplementationResponse) {
+	if a.CustomType == nil && a.ElementType == nil {
+		resp.Diagnostics.Append(fwschema.AttributeMissingElementTypeDiag(req.Path))
+	}
+}

datasource/schema/list_attribute_test.go

@@ -1,15 +1,19 @@
 package schema_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/datasource/schema"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema"
 	"github.com/hashicorp/terraform-plugin-framework/internal/testing/testschema"
+	testtypes "github.com/hashicorp/terraform-plugin-framework/internal/testing/types"
+	"github.com/hashicorp/terraform-plugin-framework/path"
 	"github.com/hashicorp/terraform-plugin-framework/schema/validator"
 	"github.com/hashicorp/terraform-plugin-framework/types"
 	"github.com/hashicorp/terraform-plugin-go/tftypes"
@@ -424,3 +428,71 @@ func TestListAttributeListValidators(t *testing.T) {
 		})
 	}
 }
+
+func TestListAttributeValidateImplementation(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		attribute schema.ListAttribute
+		request   fwschema.ValidateImplementationRequest
+		expected  *fwschema.ValidateImplementationResponse
+	}{
+		"customtype": {
+			attribute: schema.ListAttribute{
+				Computed:   true,
+				CustomType: testtypes.ListType{},
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{},
+		},
+		"elementtype": {
+			attribute: schema.ListAttribute{
+				Computed:    true,
+				ElementType: types.StringType,
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{},
+		},
+		"elementtype-missing": {
+			attribute: schema.ListAttribute{
+				Computed: true,
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{
+				Diagnostics: diag.Diagnostics{
+					diag.NewErrorDiagnostic(
+						"Invalid Attribute Implementation",
+						"When validating the schema, an implementation issue was found. "+
+							"This is always an issue with the provider and should be reported to the provider developers.\n\n"+
+							"\"test\" is missing the CustomType or ElementType field on a collection Attribute. "+
+							"One of these fields is required to prevent other unexpected errors or panics.",
+					),
+				},
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		name, testCase := name, testCase
+
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			got := &fwschema.ValidateImplementationResponse{}
+			testCase.attribute.ValidateImplementation(context.Background(), testCase.request, got)
+
+			if diff := cmp.Diff(got, testCase.expected); diff != "" {
+				t.Errorf("unexpected difference: %s", diff)
+			}
+		})
+	}
+}

datasource/schema/map_attribute.go

@@ -1,6 +1,8 @@
 package schema
 
 import (
+	"context"
+
 	"github.com/hashicorp/terraform-plugin-framework/attr"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema/fwxschema"
@@ -12,8 +14,9 @@ import (
 
 // Ensure the implementation satisifies the desired interfaces.
 var (
-	_ Attribute                            = MapAttribute{}
-	_ fwxschema.AttributeWithMapValidators = MapAttribute{}
+	_ Attribute                                    = MapAttribute{}
+	_ fwschema.AttributeWithValidateImplementation = MapAttribute{}
+	_ fwxschema.AttributeWithMapValidators         = MapAttribute{}
 )
 
 // MapAttribute represents a schema attribute that is a list with a single
@@ -198,3 +201,13 @@ func (a MapAttribute) IsSensitive() bool {
 func (a MapAttribute) MapValidators() []validator.Map {
 	return a.Validators
 }
+
+// ValidateImplementation contains logic for validating the
+// provider-defined implementation of the attribute to prevent unexpected
+// errors or panics. This logic runs during the GetProviderSchema RPC
+// and should never include false positives.
+func (a MapAttribute) ValidateImplementation(ctx context.Context, req fwschema.ValidateImplementationRequest, resp *fwschema.ValidateImplementationResponse) {
+	if a.CustomType == nil && a.ElementType == nil {
+		resp.Diagnostics.Append(fwschema.AttributeMissingElementTypeDiag(req.Path))
+	}
+}

datasource/schema/map_attribute_test.go

@@ -1,15 +1,19 @@
 package schema_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/datasource/schema"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema"
 	"github.com/hashicorp/terraform-plugin-framework/internal/testing/testschema"
+	testtypes "github.com/hashicorp/terraform-plugin-framework/internal/testing/types"
+	"github.com/hashicorp/terraform-plugin-framework/path"
 	"github.com/hashicorp/terraform-plugin-framework/schema/validator"
 	"github.com/hashicorp/terraform-plugin-framework/types"
 	"github.com/hashicorp/terraform-plugin-go/tftypes"
@@ -424,3 +428,71 @@ func TestMapAttributeMapValidators(t *testing.T) {
 		})
 	}
 }
+
+func TestMapAttributeValidateImplementation(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		attribute schema.MapAttribute
+		request   fwschema.ValidateImplementationRequest
+		expected  *fwschema.ValidateImplementationResponse
+	}{
+		"customtype": {
+			attribute: schema.MapAttribute{
+				Computed:   true,
+				CustomType: testtypes.MapType{},
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{},
+		},
+		"elementtype": {
+			attribute: schema.MapAttribute{
+				Computed:    true,
+				ElementType: types.StringType,
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{},
+		},
+		"elementtype-missing": {
+			attribute: schema.MapAttribute{
+				Computed: true,
+			},
+			request: fwschema.ValidateImplementationRequest{
+				Name: "test",
+				Path: path.Root("test"),
+			},
+			expected: &fwschema.ValidateImplementationResponse{
+				Diagnostics: diag.Diagnostics{
+					diag.NewErrorDiagnostic(
+						"Invalid Attribute Implementation",
+						"When validating the schema, an implementation issue was found. "+
+							"This is always an issue with the provider and should be reported to the provider developers.\n\n"+
+							"\"test\" is missing the CustomType or ElementType field on a collection Attribute. "+
+							"One of these fields is required to prevent other unexpected errors or panics.",
+					),
+				},
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		name, testCase := name, testCase
+
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			got := &fwschema.ValidateImplementationResponse{}
+			testCase.attribute.ValidateImplementation(context.Background(), testCase.request, got)
+
+			if diff := cmp.Diff(got, testCase.expected); diff != "" {
+				t.Errorf("unexpected difference: %s", diff)
+			}
+		})
+	}
+}

datasource/schema/object_attribute.go

@@ -1,6 +1,8 @@
 package schema
 
 import (
+	"context"
+
 	"github.com/hashicorp/terraform-plugin-framework/attr"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema"
 	"github.com/hashicorp/terraform-plugin-framework/internal/fwschema/fwxschema"
@@ -12,8 +14,9 @@ import (
 
 // Ensure the implementation satisifies the desired interfaces.
 var (
-	_ Attribute                               = ObjectAttribute{}
-	_ fwxschema.AttributeWithObjectValidators = ObjectAttribute{}
+	_ Attribute                                    = ObjectAttribute{}
+	_ fwschema.AttributeWithValidateImplementation = ObjectAttribute{}
+	_ fwxschema.AttributeWithObjectValidators      = ObjectAttribute{}
 )
 
 // ObjectAttribute represents a schema attribute that is an object with only
@@ -197,3 +200,13 @@ func (a ObjectAttribute) IsSensitive() bool {
 func (a ObjectAttribute) ObjectValidators() []validator.Object {
 	return a.Validators
 }
+
+// ValidateImplementation contains logic for validating the
+// provider-defined implementation of the attribute to prevent unexpected
+// errors or panics. This logic runs during the GetProviderSchema RPC
+// and should never include false positives.
+func (a ObjectAttribute) ValidateImplementation(ctx context.Context, req fwschema.ValidateImplementationRequest, resp *fwschema.ValidateImplementationResponse) {
+	if a.AttributeTypes == nil && a.CustomType == nil {
+		resp.Diagnostics.Append(fwschema.AttributeMissingAttributeTypesDiag(req.Path))
+	}
+}