fix(require-jsdoc): ensure exemptEmptyFunctions doesn't attempt to apply when non-function contexts are in use (causing errors); fixes #501

Author: brettz9

README.md

@@ -7772,6 +7772,12 @@ export interface Foo extends Bar {
 }
 // Options: [{"contexts":["TSMethodSignature"]}]
 // Message: Missing JSDoc comment.
+
+class MyClass {
+  someProperty: boolean; // Flow type annotation.
+}
+// Options: [{"exemptEmptyFunctions":true,"require":{"ClassDeclaration":true}}]
+// Message: Missing JSDoc comment.
 ````
 
 The following patterns are not considered problems:

src/rules/requireJsdoc.js

@@ -124,14 +124,14 @@ export default {
 
     const {require: requireOption, publicOnly, exemptEmptyFunctions} = getOptions(context);
 
-    const checkJsDoc = (node) => {
+    const checkJsDoc = (node, isFunctionContext) => {
       const jsDocNode = getJSDocComment(sourceCode, node, settings);
 
       if (jsDocNode) {
         return;
       }
 
-      if (exemptEmptyFunctions) {
+      if (exemptEmptyFunctions && isFunctionContext) {
         const functionParameterNames = jsdocUtils.getFunctionParameterNames(node);
         if (!functionParameterNames.length && !jsdocUtils.hasReturnValue(node, context)) {
           return;
@@ -194,7 +194,7 @@ export default {
             return;
           }
 
-          checkJsDoc(node);
+          checkJsDoc(node, true);
         },
 
         ClassDeclaration (node) {
@@ -218,12 +218,12 @@ export default {
             return;
           }
 
-          checkJsDoc(node);
+          checkJsDoc(node, true);
         },
 
         FunctionExpression (node) {
           if (requireOption.MethodDefinition && node.parent.type === 'MethodDefinition') {
-            checkJsDoc(node);
+            checkJsDoc(node, true);
 
             return;
           }
@@ -236,7 +236,7 @@ export default {
             ['VariableDeclarator', 'AssignmentExpression', 'ExportDefaultDeclaration'].includes(node.parent.type) ||
             node.parent.type === 'Property' && node === node.parent.value
           ) {
-            checkJsDoc(node);
+            checkJsDoc(node, true);
           }
         },
       },

test/rules/assertions/requireJsdoc.js

@@ -1166,6 +1166,25 @@ export default {
       }],
       parser: require.resolve('@typescript-eslint/parser'),
     },
+    {
+      code: `
+      class MyClass {
+        someProperty: boolean; // Flow type annotation.
+      }
+      `,
+      errors: [
+        {
+          message: 'Missing JSDoc comment.',
+        },
+      ],
+      options: [{
+        exemptEmptyFunctions: true,
+        require: {
+          ClassDeclaration: true,
+        },
+      }],
+      parser: require.resolve('babel-eslint'),
+    },
   ],
   valid: [{
     code: `