Add option and specs (no implementation yet)

These new snapshots are from https://github.com/prettier/prettier/pull/2676

docs/options.md

@@ -96,6 +96,19 @@ Put the `>` of a multi-line JSX element at the end of the last line instead of b
 | ------- | ------------------------- | ---------------------------- |
 | `false` | `--jsx-bracket-same-line` | `jsxBracketSameLine: <bool>` |
 
+# Arrow Function Parentheses
+
+Include parentheses around a sole arrow function parameter.
+
+Valid options:
+
+* `"avoid"` - Omit parens when possible. Example: `x => x`
+* `"always"` - Always include parens. Example: `(x) => x`
+
+| Default   | CLI Override                                              | API Override                                                 |
+| --------- | --------------------------------------------------------- | -------------------------------------------------------      |
+| `"avoid"` | <code>--arrow-function-parens <avoid&#124;always></code>  | <code>arrowFunctionParentheses: "<avoid&#124;always>"</code> |
+
 ## Range
 
 Format only a segment of a file.

src/cli-constant.js

@@ -77,6 +77,23 @@ const categoryOrder = [
  * Note: The options below are sorted alphabetically.
  */
 const detailedOptions = normalizeDetailedOptions({
+  "arrow-function-parentheses": {
+    type: "choice",
+    category: CATEGORY_FORMAT,
+    forwardToApi: true,
+    description: "Include parentheses around a sole arrow function parameter.",
+    default: "avoid",
+    choices: [
+      {
+        value: "avoid",
+        description: "Omit parens when possible. Example: `x => x`"
+      },
+      {
+        value: "always",
+        description: "Always include parens. Example: `(x) => x`"
+      }
+    ]
+  },
   "bracket-spacing": {
     type: "boolean",
     category: CATEGORY_FORMAT,

src/options.js

@@ -21,7 +21,8 @@ const defaults = {
   insertPragma: false,
   requirePragma: false,
   semi: true,
-  proseWrap: true
+  proseWrap: true,
+  arrowFunctionParentheses: "avoid"
 };
 
 const exampleConfig = Object.assign({}, defaults, {

tests/arrow-call/__snapshots__/jsfmt.spec.js.snap

@@ -189,3 +189,98 @@ const composition = (ViewComponent, ContainerComponent) =>
   };
 
 `;
+
+exports[`arrow_call.js 3`] = `
+const testResults = results.testResults.map(testResult =>
+  formatResult(testResult, formatter, reporter)
+);
+
+it('mocks regexp instances', () => {
+  expect(
+    () => moduleMocker.generateFromMetadata(moduleMocker.getMetadata(/a/)),
+  ).not.toThrow();
+});
+
+expect(() => asyncRequest({ url: "/test-endpoint" }))
+  .toThrowError(/Required parameter/);
+
+expect(() => asyncRequest({ url: "/test-endpoint-but-with-a-long-url" }))
+  .toThrowError(/Required parameter/);
+
+expect(() => asyncRequest({ url: "/test-endpoint-but-with-a-suuuuuuuuper-long-url" }))
+  .toThrowError(/Required parameter/);
+
+expect(() => asyncRequest({ type: "foo", url: "/test-endpoint" }))
+  .not.toThrowError();
+
+expect(() => asyncRequest({ type: "foo", url: "/test-endpoint-but-with-a-long-url" }))
+  .not.toThrowError();
+
+const a = Observable
+  .fromPromise(axiosInstance.post('/carts/mine'))
+  .map((response) => response.data)
+
+const b = Observable.fromPromise(axiosInstance.get(url))
+  .map((response) => response.data)
+
+func(
+  veryLoooooooooooooooooooooooongName,
+  veryLooooooooooooooooooooooooongName =>
+    veryLoooooooooooooooongName.something()
+);
+
+const composition = (ViewComponent, ContainerComponent) =>
+  class extends React.Component {
+    static propTypes = {};
+  };
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+const testResults = results.testResults.map(testResult =>
+  formatResult(testResult, formatter, reporter)
+);
+
+it("mocks regexp instances", () => {
+  expect(() =>
+    moduleMocker.generateFromMetadata(moduleMocker.getMetadata(/a/))
+  ).not.toThrow();
+});
+
+expect(() => asyncRequest({ url: "/test-endpoint" })).toThrowError(
+  /Required parameter/
+);
+
+expect(() =>
+  asyncRequest({ url: "/test-endpoint-but-with-a-long-url" })
+).toThrowError(/Required parameter/);
+
+expect(() =>
+  asyncRequest({ url: "/test-endpoint-but-with-a-suuuuuuuuper-long-url" })
+).toThrowError(/Required parameter/);
+
+expect(() =>
+  asyncRequest({ type: "foo", url: "/test-endpoint" })
+).not.toThrowError();
+
+expect(() =>
+  asyncRequest({ type: "foo", url: "/test-endpoint-but-with-a-long-url" })
+).not.toThrowError();
+
+const a = Observable.fromPromise(axiosInstance.post("/carts/mine")).map(
+  response => response.data
+);
+
+const b = Observable.fromPromise(axiosInstance.get(url)).map(
+  response => response.data
+);
+
+func(
+  veryLoooooooooooooooooooooooongName,
+  veryLooooooooooooooooooooooooongName =>
+    veryLoooooooooooooooongName.something()
+);
+
+const composition = (ViewComponent, ContainerComponent) =>
+  class extends React.Component {
+    static propTypes = {};
+  };
+
+`;

tests/arrow-call/jsfmt.spec.js

@@ -1,2 +1,3 @@
 run_spec(__dirname, null, ["typescript"]);
 run_spec(__dirname, { trailingComma: "all" }, ["typescript"]);
+run_spec(__dirname, { arrowFunctionParentheses: "always" }, ["typescript"]);

tests/arrows/__snapshots__/jsfmt.spec.js.snap

@@ -32,6 +32,10 @@ x => (y = z);
 x => (y += z);
 f(a => ({})) + 1;
 (a => ({})) || 0;
+a = b => c;
+a = b => {
+  return c
+};
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 (a => {}).length;
 typeof (() => {});
@@ -65,6 +69,86 @@ x => (y = z);
 x => (y += z);
 f(a => ({})) + 1;
 (a => ({})) || 0;
+a = b => c;
+a = b => {
+  return c;
+};
+
+`;
+
+exports[`arrow_function_expression.js 2`] = `
+(a => {}).length
+typeof (() => {});
+export default (() => {})();
+(() => {})()\`\`;
+(() => {})\`\`;
+new (() => {});
+if ((() => {}) ? 1 : 0) {}
+let f = () => ({}())
+let a = () => ({} instanceof a);
+a = () => ({} && a);
+a = () => ({}() && a);
+a = () => ({} && a && b);
+a = () => ({} + a);
+a = () => ({}()() && a);
+a = () => ({}.b && a);
+a = () => ({}[b] && a);
+a = () => ({}\`\` && a);
+a = () => ({} = 0);
+a = () => ({}, a);
+a => a instanceof {};
+a => ({}().b && 0)
+a => ({}().c = 0)
+x => ({}()())
+x => ({}()\`\`)
+x => ({}().b);
+a = b => c;
+a = (b?) => c;
+x => (y = z);
+x => (y += z);
+f(a => ({})) + 1;
+(a => ({})) || 0;
+a = b => c;
+a = b => {
+  return c
+};
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+(a => {}).length;
+typeof (() => {});
+export default (() => {})();
+(() => {})()\`\`;
+(() => {})\`\`;
+new (() => {})();
+if ((() => {}) ? 1 : 0) {
+}
+let f = () => ({}());
+let a = () => ({} instanceof a);
+a = () => ({} && a);
+a = () => ({}() && a);
+a = () => ({} && a && b);
+a = () => ({} + a);
+a = () => ({}()() && a);
+a = () => ({}.b && a);
+a = () => ({}[b] && a);
+a = () => ({}\`\` && a);
+a = () => ({} = 0);
+a = () => ({}, a);
+a => a instanceof {};
+a => ({}().b && 0);
+a => ({}().c = 0);
+x => ({}()());
+x => ({}()\`\`);
+x => ({}().b);
+a = b => c;
+a = (b?) => c;
+x => (y = z);
+x => (y += z);
+f(a => ({})) + 1;
+(a => ({})) || 0;
+a = b => c;
+a = b => {
+  return c;
+};
 
 `;
 
@@ -75,6 +159,13 @@ a = () => ({} = this);
 
 `;
 
+exports[`block_like.js 2`] = `
+a = () => ({} = this);
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+a = () => ({} = this);
+
+`;
+
 exports[`call.js 1`] = `
 Seq(typeDef.interface.groups).forEach(group =>
   Seq(group.members).forEach((member, memberName) =>
@@ -248,6 +339,179 @@ fooooooooooooooooooooooooooooooooooooooooooooooooooo(action => next =>
 
 `;
 
+exports[`call.js 2`] = `
+Seq(typeDef.interface.groups).forEach(group =>
+  Seq(group.members).forEach((member, memberName) =>
+    markdownDoc(
+      member.doc,
+      { typePath: typePath.concat(memberName.slice(1)),
+       signatures: member.signatures }
+    )
+  )
+)
+
+const promiseFromCallback = fn =>
+  new Promise((resolve, reject) =>
+    fn((err, result) => {
+      if (err) return reject(err);
+      return resolve(result);
+    })
+  );
+
+runtimeAgent.getProperties(
+  objectId,
+  false, // ownProperties
+  false, // accessorPropertiesOnly
+  false, // generatePreview
+  (error, properties, internalProperties) => {
+    return 1
+  },
+);
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={(e) => this.setState({progress: Math.round(100 * e.nativeEvent.loaded / e.nativeEvent.total)})}
+      />
+    </View>
+  );
+}
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={e =>
+          this.setState({
+            progress: Math.round(
+              100 * e.nativeEvent.loaded / e.nativeEvent.total,
+            ),
+          })}
+      />
+    </View>
+  );
+}
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={e =>
+          this.setState({
+            progress: Math.round(
+              100 * e.nativeEvent.loaded / e.nativeEvent.total,
+            ),
+          })}
+      />
+    </View>
+  );
+}
+
+jest.mock(
+  '../SearchSource',
+  () => class {
+    findMatchingTests(pattern) {
+      return {paths: []};
+    }
+  },
+);
+
+fooooooooooooooooooooooooooooooooooooooooooooooooooo(action => next =>
+    dispatch(action),
+);
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Seq(typeDef.interface.groups).forEach(group =>
+  Seq(group.members).forEach((member, memberName) =>
+    markdownDoc(member.doc, {
+      typePath: typePath.concat(memberName.slice(1)),
+      signatures: member.signatures
+    })
+  )
+);
+
+const promiseFromCallback = fn =>
+  new Promise((resolve, reject) =>
+    fn((err, result) => {
+      if (err) return reject(err);
+      return resolve(result);
+    })
+  );
+
+runtimeAgent.getProperties(
+  objectId,
+  false, // ownProperties
+  false, // accessorPropertiesOnly
+  false, // generatePreview
+  (error, properties, internalProperties) => {
+    return 1;
+  }
+);
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={e =>
+          this.setState({
+            progress: Math.round(
+              100 * e.nativeEvent.loaded / e.nativeEvent.total
+            )
+          })
+        }
+      />
+    </View>
+  );
+}
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={e =>
+          this.setState({
+            progress: Math.round(
+              100 * e.nativeEvent.loaded / e.nativeEvent.total
+            )
+          })
+        }
+      />
+    </View>
+  );
+}
+
+function render() {
+  return (
+    <View>
+      <Image
+        onProgress={e =>
+          this.setState({
+            progress: Math.round(
+              100 * e.nativeEvent.loaded / e.nativeEvent.total
+            )
+          })
+        }
+      />
+    </View>
+  );
+}
+
+jest.mock(
+  "../SearchSource",
+  () =>
+    class {
+      findMatchingTests(pattern) {
+        return { paths: [] };
+      }
+    }
+);
+
+fooooooooooooooooooooooooooooooooooooooooooooooooooo(action => next =>
+  dispatch(action)
+);
+
+`;
+
 exports[`comment.js 1`] = `
 /**
  * Curried function that ends with a BEM CSS Selector
@@ -313,11 +577,82 @@ export const bem = block =>
 
 `;
 
+exports[`comment.js 2`] = `
+/**
+ * Curried function that ends with a BEM CSS Selector
+ *
+ * @param {String} block - the BEM Block you'd like to select.
+ * @returns {Function}
+ */
+export const bem = block =>
+  /**
+   * @param {String} [element] - the BEM Element within that block; if undefined, selects the block itself.
+   * @returns {Function}
+   */
+  element =>
+    /**
+     * @param {?String} [modifier] - the BEM Modifier for the Block or Element; if undefined, selects the Block or Element unmodified.
+     * @returns {String}
+     */
+    modifier =>
+      [
+        ".",
+        css(block),
+        element ? \`__\${css(element)}\` : "",
+        modifier ? \`--\${css(modifier)}\` : ""
+      ].join("");
+
+<FlatList
+  renderItem={(
+    info, // $FlowExpectedError - bad widgetCount type 6, should be Object
+  ) => <span>{info.item.widget.missingProp}</span>}
+  data={data}
+/>
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+/**
+ * Curried function that ends with a BEM CSS Selector
+ *
+ * @param {String} block - the BEM Block you'd like to select.
+ * @returns {Function}
+ */
+export const bem = block =>
+  /**
+   * @param {String} [element] - the BEM Element within that block; if undefined, selects the block itself.
+   * @returns {Function}
+   */
+  element =>
+    /**
+     * @param {?String} [modifier] - the BEM Modifier for the Block or Element; if undefined, selects the Block or Element unmodified.
+     * @returns {String}
+     */
+    modifier =>
+      [
+        ".",
+        css(block),
+        element ? \`__\${css(element)}\` : "",
+        modifier ? \`--\${css(modifier)}\` : ""
+      ].join("");
+
+<FlatList
+  renderItem={(
+    info // $FlowExpectedError - bad widgetCount type 6, should be Object
+  ) => <span>{info.item.widget.missingProp}</span>}
+  data={data}
+/>;
+
+`;
+
 exports[`currying.js 1`] = `
 const fn = b => c => d => {
   return 3;
 };
 
+const foo = (a, b) => c => d => {
+  return 3;
+};
+
+const bar = a => b => c => a + b + c
+
 const mw = store => next => action => {
   return next(action)
 }
@@ -330,6 +665,51 @@ const fn = b => c => d => {
   return 3;
 };
 
+const foo = (a, b) => c => d => {
+  return 3;
+};
+
+const bar = a => b => c => a + b + c;
+
+const mw = store => next => action => {
+  return next(action);
+};
+
+const middleware = options => (req, res, next) => {
+  // ...
+};
+
+`;
+
+exports[`currying.js 2`] = `
+const fn = b => c => d => {
+  return 3;
+};
+
+const foo = (a, b) => c => d => {
+  return 3;
+};
+
+const bar = a => b => c => a + b + c
+
+const mw = store => next => action => {
+  return next(action)
+}
+
+const middleware = options => (req, res, next) => {
+  // ...
+};
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+const fn = b => c => d => {
+  return 3;
+};
+
+const foo = (a, b) => c => d => {
+  return 3;
+};
+
+const bar = a => b => c => a + b + c;
+
 const mw = store => next => action => {
   return next(action);
 };
@@ -350,6 +730,16 @@ veryLongCall(
 
 `;
 
+exports[`long-call-no-args.js 2`] = `
+veryLongCall(VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_LONG_CONSTANT, () => {})
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+veryLongCall(
+  VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_VERY_LONG_CONSTANT,
+  () => {}
+);
+
+`;
+
 exports[`long-contents.js 1`] = `
 const foo = () => {
   expect(arg1, arg2, arg3).toEqual({message: 'test', messageType: 'SMS', status: 'Unknown', created: '11/01/2017 13:36'});
@@ -366,6 +756,102 @@ const foo = () => {
 
 `;
 
+exports[`long-contents.js 2`] = `
+const foo = () => {
+  expect(arg1, arg2, arg3).toEqual({message: 'test', messageType: 'SMS', status: 'Unknown', created: '11/01/2017 13:36'});
+};
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+const foo = () => {
+  expect(arg1, arg2, arg3).toEqual({
+    message: "test",
+    messageType: "SMS",
+    status: "Unknown",
+    created: "11/01/2017 13:36"
+  });
+};
+
+`;
+
+exports[`parens.js 1`] = `
+promise.then(
+  (result) => result,
+  (err) => err
+)
+
+promise.then(
+  (result) => { f(); return result },
+  (err) => { f(); return err }
+)
+
+foo(a => b)
+foo(a => { return b })
+foo(c, a => b)
+foo(c, a => b, d)
+foo(a => b, d)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+promise.then(result => result, err => err);
+
+promise.then(
+  result => {
+    f();
+    return result;
+  },
+  err => {
+    f();
+    return err;
+  }
+);
+
+foo(a => b);
+foo(a => {
+  return b;
+});
+foo(c, a => b);
+foo(c, a => b, d);
+foo(a => b, d);
+
+`;
+
+exports[`parens.js 2`] = `
+promise.then(
+  (result) => result,
+  (err) => err
+)
+
+promise.then(
+  (result) => { f(); return result },
+  (err) => { f(); return err }
+)
+
+foo(a => b)
+foo(a => { return b })
+foo(c, a => b)
+foo(c, a => b, d)
+foo(a => b, d)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+promise.then(result => result, err => err);
+
+promise.then(
+  result => {
+    f();
+    return result;
+  },
+  err => {
+    f();
+    return err;
+  }
+);
+
+foo(a => b);
+foo(a => {
+  return b;
+});
+foo(c, a => b);
+foo(c, a => b, d);
+foo(a => b, d);
+
+`;
+
 exports[`short_body.js 1`] = `
 const initializeSnapshotState = (
   testFile: Path,
@@ -383,9 +869,33 @@ const initializeSnapshotState = (
 
 `;
 
+exports[`short_body.js 2`] = `
+const initializeSnapshotState = (
+  testFile: Path,
+  update: boolean,
+  testPath: string,
+  expand: boolean,
+) => new SnapshotState(testFile, update, testPath, expand);
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+const initializeSnapshotState = (
+  testFile: Path,
+  update: boolean,
+  testPath: string,
+  expand: boolean
+) => new SnapshotState(testFile, update, testPath, expand);
+
+`;
+
 exports[`type_params.js 1`] = `
 <T>(a) => { }
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 <T>(a) => {};
 
 `;
+
+exports[`type_params.js 2`] = `
+<T>(a) => { }
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+<T>(a) => {};
+
+`;

tests/arrows/arrow_function_expression.js

@@ -29,3 +29,7 @@ x => (y = z);
 x => (y += z);
 f(a => ({})) + 1;
 (a => ({})) || 0;
+a = b => c;
+a = b => {
+  return c
+};

tests/arrows/currying.js

@@ -2,6 +2,12 @@ const fn = b => c => d => {
   return 3;
 };
 
+const foo = (a, b) => c => d => {
+  return 3;
+};
+
+const bar = a => b => c => a + b + c
+
 const mw = store => next => action => {
   return next(action)
 }

tests/arrows/jsfmt.spec.js

@@ -1 +1,6 @@
-run_spec(__dirname, { parser: "babylon" }, ["typescript"]);
+run_spec(__dirname, { parser: "babylon", arrowFunctionParentheses: "avoid" }, [
+  "typescript"
+]);
+run_spec(__dirname, { parser: "babylon", arrowFunctionParentheses: "always" }, [
+  "typescript"
+]);

tests/arrows/parens.js

@@ -0,0 +1,15 @@
+promise.then(
+  (result) => result,
+  (err) => err
+)
+
+promise.then(
+  (result) => { f(); return result },
+  (err) => { f(); return err }
+)
+
+foo(a => b)
+foo(a => { return b })
+foo(c, a => b)
+foo(c, a => b, d)
+foo(a => b, d)

tests_integration/__tests__/__snapshots__/early-exit.js.snap

@@ -1,5 +1,23 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`show detailed usage with --help arrow-function-parentheses (stderr) 1`] = `""`;
+
+exports[`show detailed usage with --help arrow-function-parentheses (stdout) 1`] = `
+"--arrow-function-parentheses <avoid|always>
+
+  Include parentheses around a sole arrow function parameter.
+
+Valid options:
+
+  avoid    Omit parens when possible. Example: \`x => x\`
+  always   Always include parens. Example: \`(x) => x\`
+
+Default: avoid
+"
+`;
+
+exports[`show detailed usage with --help arrow-function-parentheses (write) 1`] = `Array []`;
+
 exports[`show detailed usage with --help bracket-spacing (stderr) 1`] = `""`;
 
 exports[`show detailed usage with --help bracket-spacing (stdout) 1`] = `
@@ -477,6 +495,9 @@ Output options:
 
 Format options:
 
+  --arrow-function-parentheses <avoid|always>
+                           Include parentheses around a sole arrow function parameter.
+                           Defaults to avoid.
   --no-bracket-spacing     Do not print spaces between brackets.
   --jsx-bracket-same-line  Put > on the last line instead of at a new line.
                            Defaults to false.
@@ -610,6 +631,9 @@ Output options:
 
 Format options:
 
+  --arrow-function-parentheses <avoid|always>
+                           Include parentheses around a sole arrow function parameter.
+                           Defaults to avoid.
   --no-bracket-spacing     Do not print spaces between brackets.
   --jsx-bracket-same-line  Put > on the last line instead of at a new line.
                            Defaults to false.