Add exactMatch config to RepeatingShapeNameValidator

This adds a configuration option to the repeating shape name
validator to specify that it should be an exact match rather
than a prefix check.

Author: JordonPhillips

docs/source/1.0/guides/model-linters.rst

@@ -357,10 +357,10 @@ Example:
 .. _RepeatedShapeName:
 
 RepeatedShapeName
-==================
+=================
 
 Validates that :ref:`structure` member names and :ref:`union` member
-names do not repeat their container shape names.
+names do not case-insensitively repeat their container shape names.
 
 As an example, if a structure named "Table" contained a member named
 "TableName", then this validator would emit a WARNING event.
@@ -372,6 +372,19 @@ Rationale
 Default severity
     ``WARNING``
 
+Configuration
+    .. list-table::
+       :header-rows: 1
+       :widths: 20 20 60
+
+       * - Property
+         - Type
+         - Description
+       * - exactMatch
+         - ``boolean``
+         - If set to true, the validator will only warn if the member name
+           is case-insensitively identical to the containing shape's name.
+
 
 .. _InputOutputStructureReuse:
 

smithy-linters/src/main/java/software/amazon/smithy/linters/RepeatedShapeNameValidator.java

@@ -21,6 +21,7 @@
 import java.util.Locale;
 import java.util.stream.Collectors;
 import software.amazon.smithy.model.Model;
+import software.amazon.smithy.model.node.NodeMapper;
 import software.amazon.smithy.model.shapes.Shape;
 import software.amazon.smithy.model.shapes.StructureShape;
 import software.amazon.smithy.model.shapes.UnionShape;
@@ -34,12 +35,33 @@
  */
 public final class RepeatedShapeNameValidator extends AbstractValidator {
 
+    public static final class Config {
+        private boolean exactMatch = false;
+
+        public boolean getExactMatch() {
+            return exactMatch;
+        }
+
+        public void setExactMatch(boolean exactMatch) {
+            this.exactMatch = exactMatch;
+        }
+    }
+
     public static final class Provider extends ValidatorService.Provider {
         public Provider() {
-            super(RepeatedShapeNameValidator.class, RepeatedShapeNameValidator::new);
+            super(RepeatedShapeNameValidator.class, node -> {
+                Config config = new NodeMapper().deserialize(node, Config.class);
+                return new RepeatedShapeNameValidator(config);
+            });
         }
     }
 
+    private final Config config;
+
+    private RepeatedShapeNameValidator(Config config) {
+        this.config = config;
+    }
+
     @Override
     public List<ValidationEvent> validate(Model model) {
         List<ValidationEvent> events = new ArrayList<>();
@@ -54,15 +76,30 @@ private List<ValidationEvent> validateNames(Model model, Shape shape, Collection
         String shapeName = shape.getId().getName();
         String lowerCaseShapeName = shapeName.toLowerCase(Locale.US);
         return memberNames.stream()
-                .filter(memberName -> memberName.toLowerCase(Locale.US).startsWith(lowerCaseShapeName))
+                .filter(memberName -> nameConflicts(lowerCaseShapeName, memberName))
                 .map(memberName -> repeatedMemberName(model, shape, shapeName, memberName))
                 .collect(Collectors.toList());
     }
 
+    private boolean nameConflicts(String lowerCaseShapeName, String memberName) {
+        String lowerCaseMemberName = memberName.toLowerCase(Locale.US);
+        if (config.getExactMatch()) {
+            return lowerCaseMemberName.equals(lowerCaseShapeName);
+        } else {
+            return lowerCaseMemberName.startsWith(lowerCaseShapeName);
+        }
+    }
+
     private ValidationEvent repeatedMemberName(Model model, Shape shape, String shapeName, String memberName) {
         Shape member = model.expectShape(shape.getId().withMember(memberName));
-        return warning(member, String.format(
-                "The `%s` %s shape repeats its name in the member `%s`; %2$s member names should not be "
-                        + "prefixed with the %2$s name.", shapeName, shape.getType(), memberName));
+        if (config.getExactMatch()) {
+            return warning(member, String.format(
+                    "The `%s` %s shape repeats its name in the member `%s`; %2$s member names should not be "
+                            + "equal to the %2$s name.", shapeName, shape.getType(), memberName));
+        } else {
+            return warning(member, String.format(
+                    "The `%s` %s shape repeats its name in the member `%s`; %2$s member names should not be "
+                            + "prefixed with the %2$s name.", shapeName, shape.getType(), memberName));
+        }
     }
 }

smithy-linters/src/test/resources/software/amazon/smithy/linters/errorfiles/repeated-shape-name-exact.errors

@@ -0,0 +1,2 @@
+[WARNING] smithy.example#RepeatingStructure$repeatingStructure: The `RepeatingStructure` structure shape repeats its name in the member `repeatingStructure`; structure member names should not be equal to the structure name. | RepeatedShapeName
+[WARNING] smithy.example#RepeatingUnion$repeatingUnion: The `RepeatingUnion` union shape repeats its name in the member `repeatingUnion`; union member names should not be equal to the union name. | RepeatedShapeName

smithy-linters/src/test/resources/software/amazon/smithy/linters/errorfiles/repeated-shape-name-exact.smithy

@@ -0,0 +1,22 @@
+metadata validators = [{
+    name: "RepeatedShapeName",
+    configuration: {
+        exactMatch: true
+    }
+}]
+
+namespace smithy.example
+
+structure RepeatingStructure {
+    repeatingStructure: String,
+
+    // This is fine because it's not an exact match
+    repeatingStructureMember: String,
+}
+
+union RepeatingUnion {
+    repeatingUnion: String,
+
+    // This is fine because it's not an exact match
+    repeatingUnionMember: String,
+}