Enable arrow-body-style rule (#9918)

.eslintrc.yml

@@ -13,6 +13,9 @@ plugins:
 settings:
   import/internal-regex: ^linguist-languages/
 rules:
+  arrow-body-style:
+    - error
+    - as-needed
   curly: error
   dot-notation: error
   eqeqeq:

src/language-css/utils.js

@@ -427,16 +427,16 @@ function lastLineHasInlineComment(text) {
 function stringifyNode(node) {
   if (node.groups) {
     const open = node.open && node.open.value ? node.open.value : "";
-    const groups = node.groups.reduce((previousValue, currentValue, index) => {
-      return (
+    const groups = node.groups.reduce(
+      (previousValue, currentValue, index) =>
         previousValue +
         stringifyNode(currentValue) +
         (node.groups[0].type === "comma_group" &&
         index !== node.groups.length - 1
           ? ","
-          : "")
-      );
-    }, "");
+          : ""),
+      ""
+    );
     const close = node.close && node.close.value ? node.close.value : "";
 
     return open + groups + close;

src/language-html/print-preprocess.js

@@ -440,19 +440,14 @@ function addIsSpaceSensitive(ast, options) {
 
     return node.clone({
       children: node.children
-        .map((child) => {
-          return {
-            ...child,
-            isLeadingSpaceSensitive: isLeadingSpaceSensitiveNode(
-              child,
-              options
-            ),
-            isTrailingSpaceSensitive: isTrailingSpaceSensitiveNode(
-              child,
-              options
-            ),
-          };
-        })
+        .map((child) => ({
+          ...child,
+          isLeadingSpaceSensitive: isLeadingSpaceSensitiveNode(child, options),
+          isTrailingSpaceSensitive: isTrailingSpaceSensitiveNode(
+            child,
+            options
+          ),
+        }))
         .map((child, index, children) => ({
           ...child,
           isLeadingSpaceSensitive:

src/language-js/embed/css.js

@@ -12,11 +12,17 @@ function format(path, print, textToDoc) {
   // Get full template literal with expressions replaced by placeholders
   const rawQuasis = node.quasis.map((q) => q.value.raw);
   let placeholderID = 0;
-  const text = rawQuasis.reduce((prevVal, currVal, idx) => {
-    return idx === 0
-      ? currVal
-      : prevVal + "@prettier-placeholder-" + placeholderID++ + "-id" + currVal;
-  }, "");
+  const text = rawQuasis.reduce(
+    (prevVal, currVal, idx) =>
+      idx === 0
+        ? currVal
+        : prevVal +
+          "@prettier-placeholder-" +
+          placeholderID++ +
+          "-id" +
+          currVal,
+    ""
+  );
   const doc = textToDoc(
     text,
     { parser: "scss" },

src/language-js/print/type-parameters.js

@@ -109,9 +109,7 @@ function printTypeParameter(path, options, print) {
     if (parent.nameType) {
       parts.push(
         " as ",
-        path.callParent((path) => {
-          return path.call(print, "nameType");
-        })
+        path.callParent((path) => path.call(print, "nameType"))
       );
     }
     parts.push("]");

src/language-js/printer-estree.js

@@ -563,9 +563,7 @@ function printPathNoParens(path, options, print, args) {
     case "ConditionalExpression":
       return printTernary(path, options, print);
     case "VariableDeclaration": {
-      const printed = path.map((childPath) => {
-        return print(childPath);
-      }, "declarations");
+      const printed = path.map((childPath) => print(childPath), "declarations");
 
       // We generally want to terminate all variable declarations with a
       // semicolon, except when they in the () part of for loops.

src/language-markdown/mdx.js

@@ -46,9 +46,8 @@ const tokenizeEsSyntax = (eat, value) => {
 };
 
 /* istanbul ignore next */
-tokenizeEsSyntax.locator = (value /*, fromIndex*/) => {
-  return isExport(value) || isImport(value) ? -1 : 1;
-};
+tokenizeEsSyntax.locator = (value /*, fromIndex*/) =>
+  isExport(value) || isImport(value) ? -1 : 1;
 
 function esSyntax() {
   const { Parser } = this;

src/language-markdown/printer-markdown.js

@@ -422,11 +422,10 @@ function genericPrint(path, options, print) {
                 align(
                   " ".repeat(4),
                   printChildren(path, options, print, {
-                    processor: (childPath, index) => {
-                      return index === 0
+                    processor: (childPath, index) =>
+                      index === 0
                         ? group(concat([softline, childPath.call(print)]))
-                        : childPath.call(print);
-                    },
+                        : childPath.call(print),
                   })
                 ),
                 nextNode && nextNode.type === "footnoteDefinition"

src/language-markdown/utils.js

@@ -213,9 +213,9 @@ function mapAst(ast, handler) {
 
     const newNode = { ...handler(node, index, parentStack) };
     if (newNode.children) {
-      newNode.children = newNode.children.map((child, index) => {
-        return preorder(child, index, [newNode].concat(parentStack));
-      });
+      newNode.children = newNode.children.map((child, index) =>
+        preorder(child, index, [newNode].concat(parentStack))
+      );
     }
 
     return newNode;

src/main/options-normalizer.js

@@ -166,13 +166,11 @@ function optionInfoToSchema(optionInfo, { isCLI, optionInfos }) {
   }
 
   if (optionInfo.exception) {
-    parameters.validate = (value, schema, utils) => {
-      return optionInfo.exception(value) || schema.validate(value, utils);
-    };
+    parameters.validate = (value, schema, utils) =>
+      optionInfo.exception(value) || schema.validate(value, utils);
   } else {
-    parameters.validate = (value, schema, utils) => {
-      return value === undefined || schema.validate(value, utils);
-    };
+    parameters.validate = (value, schema, utils) =>
+      value === undefined || schema.validate(value, utils);
   }
 
   /* istanbul ignore next */

tests_integration/__tests__/config-resolution.js

@@ -79,11 +79,10 @@ describe("CLI overrides take precedence", () => {
   });
 });
 
-test("API resolveConfig with no args", () => {
-  return prettier.resolveConfig().then((result) => {
+test("API resolveConfig with no args", () =>
+  prettier.resolveConfig().then((result) => {
     expect(result).toEqual({});
-  });
-});
+  }));
 
 test("API resolveConfig.sync with no args", () => {
   expect(prettier.resolveConfig.sync()).toEqual({});

website/pages/en/index.js

@@ -45,32 +45,30 @@ function Tidelift() {
   );
 }
 
-const HomeSplash = (props) => {
-  return (
-    <div className="homeContainer">
-      <Tidelift />
-      <div className="homeSplashFade">
-        <div className="wrapper homeWrapper">
-          <div className="animatedLogoWrapper">
-            <AnimatedLogo version="wide" />
-          </div>
-          <div className="inner">
-            <div className="section promoSection">
-              <div className="promoRow">
-                <div className="pluginRowBlock">
-                  <Button href="/playground/">Try It Online</Button>&nbsp;
-                  <Button href={"/docs/" + props.language + "/install.html"}>
-                    Install Prettier
-                  </Button>
-                </div>
+const HomeSplash = (props) => (
+  <div className="homeContainer">
+    <Tidelift />
+    <div className="homeSplashFade">
+      <div className="wrapper homeWrapper">
+        <div className="animatedLogoWrapper">
+          <AnimatedLogo version="wide" />
+        </div>
+        <div className="inner">
+          <div className="section promoSection">
+            <div className="promoRow">
+              <div className="pluginRowBlock">
+                <Button href="/playground/">Try It Online</Button>&nbsp;
+                <Button href={"/docs/" + props.language + "/install.html"}>
+                  Install Prettier
+                </Button>
               </div>
             </div>
           </div>
         </div>
       </div>
     </div>
-  );
-};
+  </div>
+);
 
 HomeSplash.propTypes = {
   language: PropTypes.string,
@@ -242,16 +240,12 @@ const EditorSupportSection = () => (
 
 const UsersSection = ({ language }) => {
   const showcase = siteConfig.users
-    .filter((user) => {
-      return user.pinned;
-    })
-    .map((user, i) => {
-      return (
-        <a key={i} className="growOnHover alignCenter" href={user.infoLink}>
-          <img className="user" src={user.greyImage} title={user.caption} />
-        </a>
-      );
-    });
+    .filter((user) => user.pinned)
+    .map((user, i) => (
+      <a key={i} className="growOnHover alignCenter" href={user.infoLink}>
+        <img className="user" src={user.greyImage} title={user.caption} />
+      </a>
+    ));
 
   return (
     <div className="usersSection productShowcaseSection">

website/pages/en/users/index.js

@@ -7,13 +7,11 @@ const siteConfig = require(process.cwd() + "/siteConfig.js");
 
 class Users extends React.Component {
   render() {
-    const showcase = siteConfig.users.map((user, i) => {
-      return (
-        <a key={i} href={user.infoLink}>
-          <img src={user.image} title={user.caption} />
-        </a>
-      );
-    });
+    const showcase = siteConfig.users.map((user, i) => (
+      <a key={i} href={user.infoLink}>
+        <img src={user.image} title={user.caption} />
+      </a>
+    ));
 
     return (
       <div>

website/playground/markdown.js

@@ -27,9 +27,7 @@ function formatMarkdown(
       isIdempotent ? [] : ["", "**Second Output:**", codeBlock(output2, syntax)]
     )
     .concat(full ? ["", "**Expected behavior:**", ""] : [])
-    .filter((part) => {
-      return part != null;
-    })
+    .filter((part) => part != null)
     .join("\n");
 }