// This comment goes missing
value={4}
>
Test
);
```
#### Handlebars: Avoid adding unwanted line breaks between text and mustaches ([#6186] by [@gavinjoyce])
Previously, Prettier added line breaks between text and mustaches which resulted in unwanted whitespace in rendered output.
```hbs
Your username is @{{name}}
Hi {{firstName}} {{lastName}}
Your username is @
{{name}}
Hi
{{firstName}}
{{lastName}}
Your username is @{{name}}
Hi {{firstName}} {{lastName}}
```
#### Handlebars: Improve comment formatting ([#6206] by [@gavinjoyce])
Previously, Prettier would sometimes ignore whitespace when formatting comments.
```hbs
{{! Foo }}
{{#if @foo}}
Foo
{{/if}}
{{! Bar }}
{{#if @bar}}
Bar
{{/if}}
{{! Foo }}
{{#if @foo}}
Foo
{{/if}}{{! Bar }}{{#if @bar}}
Bar
{{/if}}
{{! Foo }}
{{#if @foo}}
Foo
{{/if}}
{{! Bar }}
{{#if @bar}}
Bar
{{/if}}
```
#### JavaScript: Update `??` precedence to match stage 3 proposal ([#6404] by [@vjeux])
We've updated Prettier's support for the nullish coalescing operator to match a spec update that no longer allows it to immediately contain, or be contained within an `&&` or `||` operation.
```js
// Input
(foo ?? baz) || baz;
// Output (Prettier stable)
foo ?? baz || baz;
// Output (Prettier master)
(foo ?? baz) || baz;
```
Please note, as we update our parsers with versions that support this spec update, code without the parenthesis will throw a parse error.
#### JavaScript: Keep parentheses with comments in unary expressions ([#6217] by [@sosukesuzuki])
```ts
// Input
!(
/* foo */
foo
);
!(
foo // foo
);
// Output (Prettier stable)
!/* foo */
foo;
!foo; // foo
// Output (Prettier master)
!(/* foo */ foo);
!(
foo // foo
);
```
#### Javascript: Use function literals in arguments to detect function composition ([#6033] by [@brainkim])
Previously, we used a set of hard-coded names related to functional programming
(`compose`, `flow`, `pipe`, etc.) to detect function composition and chaining
patterns in code. This was done so that Prettier would not put code like the
following call to `pipe` on the same line even if it fit within the allotted
column budget:
```js
source$
.pipe(
filter(x => x % 2 === 0),
map(x => x + x),
scan((acc, x) => acc + x, 0),
)
.subscribe(x => console.log(x));
```
However, this heuristic caused people to complain because of false positives
where calls to functions or methods matching the hard-coded names would always
be split on multiple lines, even if the calls did not contain function
arguments ([#5769](https://github.com/prettier/prettier/issues/5769), [#5969](https://github.com/prettier/prettier/issues/5969)). For many, this blanket
decision to split functions based on name was both surprising and sub-optimal.
We now use a refined heuristic which uses the presence of function literals to
detect function composition. This heuristic preserves the line-splitting
behavior above and eliminates many if not all of the false positives caused by
the older heuristic.
We encourage prettier users to try out the new heuristic and provide feedback.
```js
// Input
eventStore.update(id, _.flow(updater, incrementVersion));
// Output (Prettier stable)
eventStore.update(
id,
_.flow(
updater,
incrementVersion
)
);
// Output (Prettier master)
eventStore.update(id, _.flow(updater, incrementVersion));
```
#### Handlebars: Preserve HTML entities ([#6234] by [@gavinjoyce])
```hbs
Some escaped characters: < > &
Some escaped characters: < > &
Some escaped characters: < > &
```
#### JavaScript: Stop moving comments inside tagged template literals ([#6236] by [@sosukesuzuki])
```js
// Input
foo //comment
`
`;
// Output (Prettier stable)
foo` // comment
`;
// Output (Prettier master)
foo // comment
`
`;
```
#### TypeScript/Flow: Fix moving comments in function calls like `useEffect` ([#6270] by [@sosukesuzuki])
This fixes a bug that was affecting function calls with an arrow function as the first argument and an array expression as the second argument, e.g. React's `useEffect`.
If a comment was placed on the line before the second argument, Prettier would move it to the line above and corrupt the indentation.
The bug was only present when using the Flow and TypeScript parsers.
```js
// Input
useEffect(
() => {
console.log("some code", props.foo);
},
// eslint-disable-line react-hooks/exhaustive-deps
[]
);
// Output (Prettier stable)
useEffect(() => {
console.log("some code", props.foo);
}, // eslint-disable-line react-hooks/exhaustive-deps
[]);
// Output (Prettier master)
useEffect(
() => {
console.log("some code", props.foo);
},
// eslint-disable-line react-hooks/exhaustive-deps
[]
);
```
#### TypeScript: Fix crashes when using `//` in JSX texts ([#6289] by [@duailibe])
This version updates the TypeScript parser to correctly handle JSX text with double slashes (`//`). In previous versions, this would cause Prettier to crash.
#### HTML, Vue: Don't wrap `template` elements on lines shorter than `printWidth` ([#6284] by [@sosukesuzuki])
Previously, even if the line length was shorter than `printWidth`, Prettier would break the line with a `template` element.
```html
foo
foo
foo
```
#### JavaScript: Empty lines in destructured arrow function parameters could break indentation and idempotence ([#6301] & [#6382] by [@sosukesuzuki])
Previously, Prettier indented code strangely when an arrow function whose parameters included an object pattern was passed to a function call as an argument. Also, it broke idempotence. Please see [#6294](https://github.com/prettier/prettier/issues/6294) for details.
```js
// Input
foo(
({
a,
b
}) => {}
);
// Output (Prettier stable)
foo(({ a,
b }) => {});
// Output (Prettier master)
foo(
({
a,
b
}) => {}
);
```
#### TypeScript: Put a closing parenthesis onto a new line after union types ([#6307] by [@sosukesuzuki])
```ts
// Input
const foo = [abc, def, ghi, jkl, mno, pqr, stu, vwx, yz] as (
| string
| undefined
)[];
// Prettier (stable)
const foo = [abc, def, ghi, jkl, mno, pqr, stu, vwx, yz] as (
| string
| undefined)[];
// Prettier (master)
const foo = [abc, def, ghi, jkl, mno, pqr, stu, vwx, yz] as (
| string
| undefined
)[];
```
#### HTML: Script tags are now treated as blocks for the purposes of formatting ([#6423] by [@thorn0])
Previously, in the [whitespace-sensitive mode](https://prettier.io/docs/en/options.html#html-whitespace-sensitivity), they were formatted as if they were inline.
```html
```
#### TypeScript: Correctly format long one-line mapped types in one pass ([#6420] by [@sosukesuzuki])
Previously, when Prettier formatted long one-line mapped types, it would break the line but didn’t add a semicolon until you ran Prettier again, which means Prettier’s idempotence rule was broken. Now, Prettier adds the semicolon in the first run.
```ts
// Input
type FooBar = { [P in keyof T]: T[P] extends Something ? Something : T[P] }
// Prettier (stable)
type FooBar = {
[P in keyof T]: T[P] extends Something ? Something : T[P]
};
// Prettier (master)
type FooBar = {
[P in keyof T]: T[P] extends Something ? Something : T[P];
};
```
#### JavaScript: Fix formatting of object destructuring with parameter decorators ([#6411] by [@sosukesuzuki])
Previously, Prettier formatted decorators for destructured parameters in a weird way. Now, parameter decorators are placed just above the parameter they belong to.
```js
// Input
class Class {
method(
@decorator
{ foo }
) {}
}
// Prettier (stable)
class Class {
method(@decorator
{
foo
}) {}
}
// Prettier (master)
class Class {
method(
@decorator
{ foo }
) {}
}
```
#### JavaScript: Handle empty object patterns with type annotations in function parameters ([#6438] by [@bakkot])
```js
// Input
const f = ({}: MyVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLongType) => {};
function g({}: Foo) {}
// Output (Prettier stable)
const f = ({
,
}: MyVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLongType) => {};
function g({ }: Foo) {}
// Output (Prettier master)
const f = ({}: MyVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLongType) => {};
function g({}: Foo) {}
```
#### JavaScript: Put a closing parenthesis onto a new line after binary expressions within function calls ([#6441] by [@sosukesuzuki])
```js
// Input
(
aaaaaaaaaaaaaaaaaaaaaaaaa &&
bbbbbbbbbbbbbbbbbbbbbbbbb &&
ccccccccccccccccccccccccc &&
ddddddddddddddddddddddddd &&
eeeeeeeeeeeeeeeeeeeeeeeee
)();
// Prettier (stable)
(aaaaaaaaaaaaaaaaaaaaaaaaa &&
bbbbbbbbbbbbbbbbbbbbbbbbb &&
ccccccccccccccccccccccccc &&
ddddddddddddddddddddddddd &&
eeeeeeeeeeeeeeeeeeeeeeeee)();
// Prettier (master)
(
aaaaaaaaaaaaaaaaaaaaaaaaa &&
bbbbbbbbbbbbbbbbbbbbbbbbb &&
ccccccccccccccccccccccccc &&
ddddddddddddddddddddddddd &&
eeeeeeeeeeeeeeeeeeeeeeeee
)();
```
#### JavaScript: Fix formatting of long named exports ([#6446] by [@sosukesuzuki])
Now, Prettier formats them the same way it formats named imports.
```js
// Input
export { fooooooooooooooooooooooooooooooooooooooooooooooooo } from "fooooooooooooooooooooooooooooo";
// Prettier (stable)
export {
fooooooooooooooooooooooooooooooooooooooooooooooooo
} from "fooooooooooooooooooooooooooooo";
// Prettier (master)
export { fooooooooooooooooooooooooooooooooooooooooooooooooo } from "fooooooooooooooooooooooooooooo";
```
#### JavaScript: Fix bad formatting for multi-line optional chaining with comment ([#6506] by [@sosukesuzuki])
```js
// Input
return a
.b()
.c()
// Comment
?.d()
// Prettier (stable)
return a
.b()
.c()
?.// Comment
d();
// Prettier (master)
return (
a
.b()
.c()
// Comment
?.d()
);
```
#### JavaScript: Fix inconsistent indentation in switch statement ([#6514] by [@sosukesuzuki])
```js
// Input
switch ($veryLongAndVeryVerboseVariableName && $anotherVeryLongAndVeryVerboseVariableName) {
}
switch ($longButSlightlyShorterVariableName && $anotherSlightlyShorterVariableName) {
}
// Prettier (stable)
switch (
$veryLongAndVeryVerboseVariableName &&
$anotherVeryLongAndVeryVerboseVariableName
) {
}
switch (
$longButSlightlyShorterVariableName && $anotherSlightlyShorterVariableName
) {
}
// Prettier (master)
switch (
$veryLongAndVeryVerboseVariableName &&
$anotherVeryLongAndVeryVerboseVariableName
) {
}
switch (
$longButSlightlyShorterVariableName &&
$anotherSlightlyShorterVariableName
) {
}
```
#### TypeScript: Keep type parameters inline for type annotations in variable declarations ([#6467] by [@sosukesuzuki])
```ts
// Input
const fooooooooooooooo: SomeThing = looooooooooooooooooooooooooooooongNameFunc();
// Prettier (stable)
const fooooooooooooooo: SomeThing<
boolean
> = looooooooooooooooooooooooooooooongNameFunc();
// Prettier (master)
const fooooooooooooooo: SomeThing = looooooooooooooooooooooooooooooongNameFunc();
```
#### Handlebars: Fix `--single-quote` option on HTML attributes ([#6377] by [@dcyriller])
Previously, the flag was not applied on HTML attributes.
```hbs
```
#### TypeScript: Sometimes double parentheses around types were removed incorrectly ([#6604] by [@sosukesuzuki])
```ts
// Input
type A = 0 extends ((1 extends 2 ? 3 : 4)) ? 5 : 6;
type B = ((0 extends 1 ? 2 : 3)) extends 4 ? 5 : 6;
type C = ((number | string))["toString"];
type D = ((keyof T1))["foo"];
// Prettier (stable)
type A = 0 extends 1 extends 2 ? 3 : 4 ? 5 : 6;
type B = 0 extends 1 ? 2 : 3 extends 4 ? 5 : 6;
type C = number | string["toString"];
type D = keyof T1["foo"];
// Prettier (master)
type A = 0 extends (1 extends 2 ? 3 : 4) ? 5 : 6;
type B = (0 extends 1 ? 2 : 3) extends 4 ? 5 : 6;
type C = (number | string)["toString"];
type D = (keyof T1)["foo"];
```
#### JavaScript: Support formatting code with V8 intrinsics ([#6496] by [@rreverser])
```js
// Input
function doSmth() {
%DebugPrint
(
foo )
}
// Prettier (stable)
SyntaxError: Unexpected token (2:13)
1 | function doSmth() {
> 2 | %DebugPrint
| ^
// Prettier (master)
function doSmth() {
%DebugPrint(foo);
}
```
#### TypeScript: Sometimes removing parentheses around JSX made the code unparseable ([#6640] by [@sosukesuzuki])
```tsx
// Input
().toString();
// Prettier (stable)
.toString():
// Prettier (master)
().toString();
```
#### JavaScript: Object destructuring in method parameters always broke into multiple lines ([#6646] by [@ericsakmar])
```js
// Input
const obj = {
func(id, { blog: { title } }) {
return id + title;
},
};
class A {
func(id, { blog: { title } }) {
return id + title;
}
#func(id, { blog: { title } }) {
return id + title;
}
}
// Prettier (stable)
const obj = {
func(
id,
{
blog: { title }
}
) {
return id + title;
}
};
class A {
func(
id,
{
blog: { title }
}
) {
return id + title;
}
#func(
id,
{
blog: { title }
}
) {
return id + title;
}
}
// Prettier (master)
const obj = {
func(id, { blog: { title } }) {
return id + title;
},
};
class A {
func(id, { blog: { title } }) {
return id + title;
}
#func(id, { blog: { title } }) {
return id + title;
}
}
```
#### TypeScript: Fix optional computed methods ([#6673] by [@thorn0])
```ts
// Input
class A {
protected [s]?() {}
}
// Output (Prettier stable)
class A {
protected [s?]() {}
}
// Output (Prettier master)
class A {
protected [s]?() {}
}
```
#### Angular: Put a closing parenthesis onto a new line after ternaries passed to pipes ([#5682] by [@selvazhagan])
```html
{{ (isCustomDiscount ? 'DISCOUNTS__DISCOUNT_TRAINING_HEADER__CUSTOM_DISCOUNT' : 'DISCOUNTS__DISCOUNT_TRAINING_HEADER__DISCOUNT') | translate }}
{{
(isCustomDiscount
? "DISCOUNTS__DISCOUNT_TRAINING_HEADER__CUSTOM_DISCOUNT"
: "DISCOUNTS__DISCOUNT_TRAINING_HEADER__DISCOUNT") | translate
}}
{{
(isCustomDiscount
? "DISCOUNTS__DISCOUNT_TRAINING_HEADER__CUSTOM_DISCOUNT"
: "DISCOUNTS__DISCOUNT_TRAINING_HEADER__DISCOUNT"
) | translate
}}
```
#### Handlebars: Fix handling of whitespace and line breaks ([#6354] by [@chadian])
This fixes a variety of whitespace and line break use cases within Handlebars and Glimmer templates.
```hbs
{{name}}
Some sentence with {{dynamic}} expressions.
sometimes{{nogaps}}areimportant
{{name}} is your name
{{name}}
Some sentence with
{{dynamic}}
expressions.
sometimes
{{nogaps}}
areimportant
{{name}}
is your name
{{name}}
Some sentence with {{dynamic}} expressions.
sometimes{{nogaps}}areimportant
{{name}} is your name
```
#### JavaScript: Break arrays of arrays/objects if each element has more than one element/property ([#6694] by [@sosukesuzuki])
```js
// Input
test.each([
{ a: "1", b: 1 },
{ a: "2", b: 2 },
{ a: "3", b: 3 }
])("test", ({ a, b }) => {
expect(Number(a)).toBe(b);
});
[[0, 1, 2], [0, 1, 2]];
new Map([
[A, B],
[C, D],
[E, F],
[G, H],
[I, J],
[K, L],
[M, N]
]);
// Output (Prettier stable)
test.each([{ a: "1", b: 1 }, { a: "2", b: 2 }, { a: "3", b: 3 }])(
"test",
({ a, b }) => {
expect(Number(a)).toBe(b);
}
);
[[0, 1, 2], [0, 1, 2]]
new Map([[A, B], [C, D], [E, F], [G, H], [I, J], [K, L], [M, N]]);
// Output (Prettier master)
test.each([
{ a: "1", b: 1 },
{ a: "2", b: 2 },
{ a: "3", b: 3 }
])("test", ({ a, b }) => {
expect(Number(a)).toBe(b);
});
[
[0, 1, 2],
[0, 1, 2]
];
new Map([
[A, B],
[C, D],
[E, F],
[G, H],
[I, J],
[K, L],
[M, N]
]);
```
[#5682]: https://github.com/prettier/prettier/pull/5682
[#5910]: https://github.com/prettier/prettier/pull/5910
[#6033]: https://github.com/prettier/prettier/pull/6033
[#6186]: https://github.com/prettier/prettier/pull/6186
[#6206]: https://github.com/prettier/prettier/pull/6206
[#6209]: https://github.com/prettier/prettier/pull/6209
[#6217]: https://github.com/prettier/prettier/pull/6217
[#6234]: https://github.com/prettier/prettier/pull/6234
[#6236]: https://github.com/prettier/prettier/pull/6236
[#6270]: https://github.com/prettier/prettier/pull/6270
[#6284]: https://github.com/prettier/prettier/pull/6284
[#6289]: https://github.com/prettier/prettier/pull/6289
[#6301]: https://github.com/prettier/prettier/pull/6301
[#6307]: https://github.com/prettier/prettier/pull/6307
[#6332]: https://github.com/prettier/prettier/pull/6332
[#6340]: https://github.com/prettier/prettier/pull/6340
[#6354]: https://github.com/prettier/prettier/pull/6354
[#6377]: https://github.com/prettier/prettier/pull/6377
[#6381]: https://github.com/prettier/prettier/pull/6381
[#6382]: https://github.com/prettier/prettier/pull/6382
[#6397]: https://github.com/prettier/prettier/pull/6397
[#6404]: https://github.com/prettier/prettier/pull/6404
[#6411]: https://github.com/prettier/prettier/pull/6411
[#6412]: https://github.com/prettier/prettier/pull/6412
[#6420]: https://github.com/prettier/prettier/pull/6420
[#6423]: https://github.com/prettier/prettier/pull/6423
[#6438]: https://github.com/prettier/prettier/pull/6411
[#6441]: https://github.com/prettier/prettier/pull/6441
[#6446]: https://github.com/prettier/prettier/pull/6446
[#6467]: https://github.com/prettier/prettier/pull/6467
[#6496]: https://github.com/prettier/prettier/pull/6496
[#6506]: https://github.com/prettier/prettier/pull/6506
[#6514]: https://github.com/prettier/prettier/pull/6514
[#6604]: https://github.com/prettier/prettier/pull/6604
[#6605]: https://github.com/prettier/prettier/pull/6605
[#6640]: https://github.com/prettier/prettier/pull/6640
[#6646]: https://github.com/prettier/prettier/pull/6646
[#6666]: https://github.com/prettier/prettier/pull/6666
[#6673]: https://github.com/prettier/prettier/pull/6673
[#6694]: https://github.com/prettier/prettier/pull/6694
[@brainkim]: https://github.com/brainkim
[@duailibe]: https://github.com/duailibe
[@gavinjoyce]: https://github.com/gavinjoyce
[@sosukesuzuki]: https://github.com/sosukesuzuki
[@g-harel]: https://github.com/g-harel
[@jounqin]: https://github.com/JounQin
[@bakkot]: https://gibhub.com/bakkot
[@thorn0]: https://github.com/thorn0
[@dcyriller]: https://github.com/dcyriller
[@rreverser]: https://github.com/RReverser
[@ericsakmar]: https://github.com/ericsakmar
[@squidfunk]: https://github.com/squidfunk
[@vjeux]: https://github.com/vjeux
[@selvazhagan]: https://github.com/selvazhagan
[@chadian]: https://github.com/chadian
[@kaicataldo]: https://github.com/kaicataldo