feat(AIP-213): Lint message fields that should use common types

docs/rules/0213/common-types-fields.md

@@ -0,0 +1,90 @@
+---
+rule:
+  aip: 213
+  name: [core, '0213', common-types-fields]
+  summary: Message fields with certain names should use a common type.
+permalink: /213/common-types-fields
+redirect_from:
+  - /0213/common-types-fields
+---
+
+# Common types fields
+
+This rule enforces that message fields with specific names use a common type, as
+recommended in [AIP-213][].
+
+## Details
+
+This rule looks at the fields in a message, and complains if it finds a field
+with a specific name that doesn't have the corresponding common type.
+
+Some example pairings of common types and field names that are checked are:
+
+* `google.protobuf.Duration`: "duration"
+* `google.type.Color`: "color", "colour"
+* `google.type.PhoneNumber`: "mobile_number", "phone", "phone_number"
+
+## Examples
+
+**Incorrect** code for this rule:
+
+```proto
+// Incorrect.
+message Book {
+  string name = 1;
+  
+  // Should use `google.type.Color`.
+  string color = 2;
+}
+```
+
+```proto
+// Incorrect.
+message Book {
+  string name = 1;
+  
+  // Should use `google.type.PhoneNumber`.
+  string phone_number = 2;
+}
+```
+
+**Correct** code for this rule:
+
+```proto
+// Correct.
+message Book {
+  string name = 1;
+  
+  google.type.Color color = 2;
+}
+```
+
+```proto
+// Correct.
+message Book {
+  string name = 1;
+  
+  google.type.PhoneNumber phone_number = 2;
+}
+```
+
+## Disabling
+
+If you need to violate this rule, use a leading comment above the enum.
+Remember to also include an [aip.dev/not-precedent][] comment explaining why.
+
+```proto
+message Book {
+  string name = 1;
+  // (-- api-linter: core::0213::common-types-fields=disabled
+  //     aip.dev/not-precedent: We need to do this because reasons. --)
+  google.protobuf.Timestamp expire_time = 2
+    [(google.api.field_behavior) = OUTPUT_ONLY];
+}
+```
+
+If you need to violate this rule for an entire file, place the comment at the
+top of the file.
+
+[aip-213]: https://aip.dev/213
+[aip.dev/not-precedent]: https://aip.dev/not-precedent

docs/rules/0213/common-types-messages.md

@@ -0,0 +1,67 @@
+---
+rule:
+  aip: 213
+  name: [core, '0213', common-types-messages]
+  summary: Messages containing fields of a common type should use the common type.
+permalink: /213/common-types-messages
+redirect_from:
+  - /0213/common-types-messages
+---
+
+# Common types messages
+
+This rule enforces that messages that contain the fields of a common type use the
+common type itself, as recommended in [AIP-213][].
+
+## Details
+
+This rule looks at the fields in a message, and complains if it finds a set of
+field names that all belong to a common type.
+
+## Examples
+
+**Incorrect** code for this rule:
+
+```proto
+// Incorrect.
+message Book {
+  string name = 1;
+  
+  // Should use `google.type.Interval`.
+  google.protobuf.Timestamp start_time = 2;
+  google.protobuf.Timestamp end_time = 3;
+}
+```
+
+**Correct** code for this rule:
+
+```proto
+// Correct.
+message Book {
+  string name = 1;
+  
+  // Should use `google.type.Interval`.
+  google.type.Interval interval = 2;
+}
+```
+
+## Disabling
+
+If you need to violate this rule, use a leading comment above the enum.
+Remember to also include an [aip.dev/not-precedent][] comment explaining why.
+
+```proto
+message Book {
+  string name = 1;
+  // (-- api-linter: core::0213::common-types-messages=disabled
+  //     aip.dev/not-precedent: We need to do this because reasons. --)
+  google.protobuf.Timestamp expire_time = 2
+    [(google.api.field_behavior) = OUTPUT_ONLY];
+}
+```
+
+If you need to violate this rule for an entire file, place the comment at the
+top of the file.
+
+[aip-213]: https://aip.dev/213
+[aip.dev/not-precedent]: https://aip.dev/not-precedent

docs/rules/0213/index.md

@@ -0,0 +1,10 @@
+---
+aip_listing: 213
+permalink: /213/
+redirect_from:
+  - /0213/
+---
+
+# Common components
+
+{% include linter-aip-listing.md aip=213 %}

rules/aip0213/aip0213.go

@@ -0,0 +1,29 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package aip0213 contains rules defined in https://aip.dev/213.
+package aip0213
+
+import (
+	"github.com/googleapis/api-linter/lint"
+)
+
+// AddRules adds all of the AIP-213 rules to the provided registry.
+func AddRules(r lint.RuleRegistry) error {
+	return r.Register(
+		213,
+		commonTypesFields,
+		commonTypesMessages,
+	)
+}

rules/aip0213/aip0213_test.go

@@ -0,0 +1,27 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aip0213
+
+import (
+	"testing"
+
+	"github.com/googleapis/api-linter/lint"
+)
+
+func TestAddRules(t *testing.T) {
+	if err := AddRules(lint.NewRuleRegistry()); err != nil {
+		t.Errorf("AddRules got an error: %v", err)
+	}
+}

rules/aip0213/common_types_fields.go

@@ -0,0 +1,63 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aip0213
+
+import (
+	"fmt"
+
+	"github.com/googleapis/api-linter/lint"
+	"github.com/jhump/protoreflect/desc"
+)
+
+var fieldNameToCommonType = map[string]string{
+	"duration": "google.protobuf.Duration",
+
+	"color":  "google.type.Color",
+	"colour": "google.type.Color",
+
+	"dollars": "google.type.Money",
+	"euros":   "google.type.Money",
+	"money":   "google.type.Money",
+	"pounds":  "google.type.Money",
+	"yen":     "google.type.Money",
+	"yuan":    "google.type.Money",
+
+	"mobile_number": "google.type.PhoneNumber",
+	"phone":         "google.type.PhoneNumber",
+	"phone_number":  "google.type.PhoneNumber",
+
+	"clock_time":  "google.type.TimeOfDay",
+	"time_of_day": "google.type.TimeOfDay",
+
+	"timezone":  "google.type.TimeZone",
+	"time_zone": "google.type.TimeZone",
+}
+
+var commonTypesFields = &lint.FieldRule{
+	Name: lint.NewRuleName(213, "common-types-fields"),
+	LintField: func(f *desc.FieldDescriptor) []lint.Problem {
+		// Flag this field if it has a name in `fieldNameToCommonType` but
+		// doesn't have its corresponding type.
+		if messageType, ok := fieldNameToCommonType[f.GetName()]; ok {
+			if f.GetMessageType() == nil || f.GetMessageType().GetFullyQualifiedName() != messageType {
+				return []lint.Problem{{
+					Message:    fmt.Sprintf("Consider using the common type %q.", messageType),
+					Descriptor: f,
+				}}
+			}
+		}
+		return nil
+	},
+}

rules/aip0213/common_types_fields_test.go

@@ -0,0 +1,48 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aip0213
+
+import (
+	"testing"
+
+	"github.com/googleapis/api-linter/rules/internal/testutils"
+)
+
+func TestCommonTypesFields(t *testing.T) {
+	for _, test := range []struct {
+		name     string
+		Field    string
+		problems testutils.Problems
+	}{
+		{"ValidCommonType", "google.protobuf.Duration duration", nil},
+		{"ValidOtherType", "string bar", nil},
+		{"FieldDoesNotUseMessageType", "map<int32, int32> duration", testutils.Problems{{Message: "common type"}}},
+		{"FieldDoesNotUseCommonType", "int32 duration", testutils.Problems{{Message: "common type"}}},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			f := testutils.ParseProto3Tmpl(t, `
+				import "google/protobuf/duration.proto";
+
+				message Foo {
+					{{.Field}} = 1;
+				}
+			`, test)
+			field := f.GetMessageTypes()[0].GetFields()[0]
+			if diff := test.problems.SetDescriptor(field).Diff(commonTypesFields.Lint(f)); diff != "" {
+				t.Errorf(diff)
+			}
+		})
+	}
+}