☂️ Documentation changes 0.9.0

[ematipico]

Tentative date, 6th September 2022

https://github.com/orgs/rome/projects/3/views/4?query=is%3Aopen+sort%3Aupdated-desc

Focus of this release

• stabilize configuration file, make sure it's exhaustive but minimal at the same time
• correctness, make sure that parser and linter work as expected, we catch errors early, and we monitor possible performance regressions
• formatter stability
• Node.js API

[MichaReiser]

Documentation changes

Document the decision on how Rome parenthesizesclass, function, and object expressions at the begin of a statement and optional chain expressions differently:

ObjectExpression, FunctionExpression, or ClassExpression at the beginning of a statement.

// input
{}.b

// Prettier
({}.b)

// Rome
({}).b 

Prettier parenthesizes the whole expression whereas Rome parenthesizes the object/function/class expression only.

The main reason for diverging is that parenthesizing the whole expression requires that the logic is implemented in any expression that starts with another child expression (tagged template, binary expressions, computed member/assignment, sequence, conditional, ... ) and it requires traversing the first expression until it reaches an object expression or any expression that doesn't start with another expression. This is rather expensive and Rome's approach avoids the expensive traversal except for object/function and class expressions, of which there should be fewer.

Parenthesized optional chain

// Input
(a?.b).c
a?.b.c

// Prettier
(a?.b).c
a?.b.c

// Rome
a?.b.c
a?.b.c

Prettier keeps the parentheses if they were present in the source document but never adds them if they were missing. This is the only case where I found that the fact that parens are present in the source document changed how Prettier parenthesizes formatted expression.

My take is that Rome should apply a consistent formatting regardless if parentheses were or were not present in the source document.

#3057

[MichaReiser]

Document quote properties option #3065

[xunilrj]

Two examples of valid noUnusedVariables:
1 - Starting with an underscore;
2 - Named React.
See https://github.com/rome/tools/pull/3124/files#diff-78c747a14dde0733f5baaa828d4ad30bcca527d46dfd380688bbad45eb291448R67