Enable "no-case-declarations" ESLint rule (#1887)

.eslintrc.yml

@@ -112,8 +112,7 @@ rules:
   max-classes-per-file: off
   no-alert: error
   no-caller: error
-  # TODO: recommended rule but disable due to errors in existing code
-  # no-case-declarations: error
+  no-case-declarations: error
   no-div-regex: error
   no-else-return: error
   no-empty-function: off # TODO

src/execution/execute.js

@@ -528,7 +528,7 @@ export function collectFields(
   for (let i = 0; i < selectionSet.selections.length; i++) {
     const selection = selectionSet.selections[i];
     switch (selection.kind) {
-      case Kind.FIELD:
+      case Kind.FIELD: {
         if (!shouldIncludeNode(exeContext, selection)) {
           continue;
         }
@@ -538,7 +538,8 @@ export function collectFields(
         }
         fields[name].push(selection);
         break;
-      case Kind.INLINE_FRAGMENT:
+      }
+      case Kind.INLINE_FRAGMENT: {
         if (
           !shouldIncludeNode(exeContext, selection) ||
           !doesFragmentConditionMatch(exeContext, selection, runtimeType)
@@ -553,7 +554,8 @@ export function collectFields(
           visitedFragmentNames,
         );
         break;
-      case Kind.FRAGMENT_SPREAD:
+      }
+      case Kind.FRAGMENT_SPREAD: {
         const fragName = selection.name.value;
         if (
           visitedFragmentNames[fragName] ||
@@ -577,6 +579,7 @@ export function collectFields(
           visitedFragmentNames,
         );
         break;
+      }
     }
   }
   return fields;

src/language/lexer.js

@@ -597,7 +597,8 @@ function readString(source, start, line, col, prev): Token {
         case 116:
           value += '\t';
           break;
-        case 117: // u
+        case 117: {
+          // uXXXX
           const charCode = uniCharCode(
             body.charCodeAt(position + 1),
             body.charCodeAt(position + 2),
@@ -615,6 +616,7 @@ function readString(source, start, line, col, prev): Token {
           value += String.fromCharCode(charCode);
           position += 4;
           break;
+        }
         default:
           throw syntaxError(
             source,

src/utilities/TypeInfo.js

@@ -144,13 +144,14 @@ export class TypeInfo {
     // checked before continuing since TypeInfo is used as part of validation
     // which occurs before guarantees of schema and document validity.
     switch (node.kind) {
-      case Kind.SELECTION_SET:
+      case Kind.SELECTION_SET: {
         const namedType: mixed = getNamedType(this.getType());
         this._parentTypeStack.push(
           isCompositeType(namedType) ? namedType : undefined,
         );
         break;
-      case Kind.FIELD:
+      }
+      case Kind.FIELD: {
         const parentType = this.getParentType();
         let fieldDef;
         let fieldType: mixed;
@@ -163,10 +164,11 @@ export class TypeInfo {
         this._fieldDefStack.push(fieldDef);
         this._typeStack.push(isOutputType(fieldType) ? fieldType : undefined);
         break;
+      }
       case Kind.DIRECTIVE:
         this._directive = schema.getDirective(node.name.value);
         break;
-      case Kind.OPERATION_DEFINITION:
+      case Kind.OPERATION_DEFINITION: {
         let type: mixed;
         if (node.operation === 'query') {
           type = schema.getQueryType();
@@ -177,21 +179,24 @@ export class TypeInfo {
         }
         this._typeStack.push(isObjectType(type) ? type : undefined);
         break;
+      }
       case Kind.INLINE_FRAGMENT:
-      case Kind.FRAGMENT_DEFINITION:
+      case Kind.FRAGMENT_DEFINITION: {
         const typeConditionAST = node.typeCondition;
         const outputType: mixed = typeConditionAST
           ? typeFromAST(schema, typeConditionAST)
           : getNamedType(this.getType());
         this._typeStack.push(isOutputType(outputType) ? outputType : undefined);
         break;
-      case Kind.VARIABLE_DEFINITION:
+      }
+      case Kind.VARIABLE_DEFINITION: {
         const inputType: mixed = typeFromAST(schema, node.type);
         this._inputTypeStack.push(
           isInputType(inputType) ? inputType : undefined,
         );
         break;
-      case Kind.ARGUMENT:
+      }
+      case Kind.ARGUMENT: {
         let argDef;
         let argType: mixed;
         const fieldOrDirective = this.getDirective() || this.getFieldDef();
@@ -208,7 +213,8 @@ export class TypeInfo {
         this._defaultValueStack.push(argDef ? argDef.defaultValue : undefined);
         this._inputTypeStack.push(isInputType(argType) ? argType : undefined);
         break;
-      case Kind.LIST:
+      }
+      case Kind.LIST: {
         const listType: mixed = getNullableType(this.getInputType());
         const itemType: mixed = isListType(listType)
           ? listType.ofType
@@ -217,7 +223,8 @@ export class TypeInfo {
         this._defaultValueStack.push(undefined);
         this._inputTypeStack.push(isInputType(itemType) ? itemType : undefined);
         break;
-      case Kind.OBJECT_FIELD:
+      }
+      case Kind.OBJECT_FIELD: {
         const objectType: mixed = getNamedType(this.getInputType());
         let inputFieldType: GraphQLInputType | void;
         let inputField: GraphQLInputField | void;
@@ -234,14 +241,16 @@ export class TypeInfo {
           isInputType(inputFieldType) ? inputFieldType : undefined,
         );
         break;
-      case Kind.ENUM:
+      }
+      case Kind.ENUM: {
         const enumType: mixed = getNamedType(this.getInputType());
         let enumValue;
         if (isEnumType(enumType)) {
           enumValue = enumType.getValue(node.value);
         }
         this._enumValue = enumValue;
         break;
+      }
     }
   }
 

src/utilities/getOperationRootType.js

@@ -22,38 +22,41 @@ export function getOperationRootType(
   schema: GraphQLSchema,
   operation: OperationDefinitionNode | OperationTypeDefinitionNode,
 ): GraphQLObjectType {
-  switch (operation.operation) {
-    case 'query':
-      const queryType = schema.getQueryType();
-      if (!queryType) {
-        throw new GraphQLError(
-          'Schema does not define the required query root type.',
-          operation,
-        );
-      }
-      return queryType;
-    case 'mutation':
-      const mutationType = schema.getMutationType();
-      if (!mutationType) {
-        throw new GraphQLError(
-          'Schema is not configured for mutations.',
-          operation,
-        );
-      }
-      return mutationType;
-    case 'subscription':
-      const subscriptionType = schema.getSubscriptionType();
-      if (!subscriptionType) {
-        throw new GraphQLError(
-          'Schema is not configured for subscriptions.',
-          operation,
-        );
-      }
-      return subscriptionType;
-    default:
+  if (operation.operation === 'query') {
+    const queryType = schema.getQueryType();
+    if (!queryType) {
       throw new GraphQLError(
-        'Can only have query, mutation and subscription operations.',
+        'Schema does not define the required query root type.',
         operation,
       );
+    }
+    return queryType;
   }
+
+  if (operation.operation === 'mutation') {
+    const mutationType = schema.getMutationType();
+    if (!mutationType) {
+      throw new GraphQLError(
+        'Schema is not configured for mutations.',
+        operation,
+      );
+    }
+    return mutationType;
+  }
+
+  if (operation.operation === 'subscription') {
+    const subscriptionType = schema.getSubscriptionType();
+    if (!subscriptionType) {
+      throw new GraphQLError(
+        'Schema is not configured for subscriptions.',
+        operation,
+      );
+    }
+    return subscriptionType;
+  }
+
+  throw new GraphQLError(
+    'Can only have query, mutation and subscription operations.',
+    operation,
+  );
 }

src/utilities/valueFromASTUntyped.js

@@ -53,11 +53,12 @@ export function valueFromASTUntyped(
         field => field.name.value,
         field => valueFromASTUntyped(field.value, variables),
       );
-    case Kind.VARIABLE:
+    case Kind.VARIABLE: {
       const variableName = valueNode.name.value;
       return variables && !isInvalid(variables[variableName])
         ? variables[variableName]
         : undefined;
+    }
   }
 
   // Not reachable. All possible value nodes have been considered.

src/validation/rules/KnownDirectives.js

@@ -127,11 +127,12 @@ function getDirectiveLocationForASTPath(ancestors) {
       case Kind.INPUT_OBJECT_TYPE_DEFINITION:
       case Kind.INPUT_OBJECT_TYPE_EXTENSION:
         return DirectiveLocation.INPUT_OBJECT;
-      case Kind.INPUT_VALUE_DEFINITION:
+      case Kind.INPUT_VALUE_DEFINITION: {
         const parentNode = ancestors[ancestors.length - 3];
         return parentNode.kind === Kind.INPUT_OBJECT_TYPE_DEFINITION
           ? DirectiveLocation.INPUT_FIELD_DEFINITION
           : DirectiveLocation.ARGUMENT_DEFINITION;
+      }
     }
   }
 }

src/validation/rules/OverlappingFieldsCanBeMerged.js

@@ -747,7 +747,7 @@ function _collectFieldsAndFragmentNames(
   for (let i = 0; i < selectionSet.selections.length; i++) {
     const selection = selectionSet.selections[i];
     switch (selection.kind) {
-      case Kind.FIELD:
+      case Kind.FIELD: {
         const fieldName = selection.name.value;
         let fieldDef;
         if (isObjectType(parentType) || isInterfaceType(parentType)) {
@@ -761,10 +761,11 @@ function _collectFieldsAndFragmentNames(
         }
         nodeAndDefs[responseName].push([parentType, selection, fieldDef]);
         break;
+      }
       case Kind.FRAGMENT_SPREAD:
         fragmentNames[selection.name.value] = true;
         break;
-      case Kind.INLINE_FRAGMENT:
+      case Kind.INLINE_FRAGMENT: {
         const typeCondition = selection.typeCondition;
         const inlineFragmentType = typeCondition
           ? typeFromAST(context.getSchema(), typeCondition)
@@ -777,6 +778,7 @@ function _collectFieldsAndFragmentNames(
           fragmentNames,
         );
         break;
+      }
     }
   }
 }