Add tests for class elements continued after a line terminator

[hexbinoct]

test262 checks that a semicolon is inserted between a field named get or set and a generator method on the next line (grammar-field-named-get-followed-by-generator-asi.js and its set sibling). It does not check the other side: when the token on the next line can continue the element, no semicolon is inserted, because only async and accessor are followed by [no LineTerminator here].

class C {
  get
  a() {}   // a getter named a, not a field named get and a method
}

engine262 gets these wrong, and nothing in the suite catches it. This adds, next to the two existing ASI tests in class/elements/syntax/valid:

• get or set, a line break, then a name: a getter or setter (prototype, static, computed and private)
• static, a line break, then a method, generator, async method or getter: a static method
• static, a line break, then a field name: a static field
• a method named static, as static(), static static() and static with ( on the next line
• a method name, a line break, then (: a method, for m, get and set
• a SyntaxError for get, a line break, then a name with no parameter list (generated, class declaration and expression)

I could not find an existing test for a class method named static. The only static() methods in the suite are object literal methods in staging/sm/class/methDefn.js.

I found this while reviewing #5134: with the escapes removed from its cases, engine262 read get, a line break and a() {} as a field and a method.

Results, default and strict mode:

node v24.14.0, v26.5.1 (V8)              8/8 pass
bun 1.3.14 (JavaScriptCore)              8/8 pass
engine262 main (a600354c)                0/8, e.g. "(A) a is a getter on the prototype Expected SameValue(«"undefined"», «"function"») to be true"
engine262 with the fix                   8/8 pass

The engine262 fix is engine262/engine262#368.

Lint is clean. To check that each test can fail, I ran mutated copies: flipping the key expectation in each positive test, and giving the getter in the negative test its parameter list. All of them fail on all four engines.

LLM disclosure: Claude Opus 5.5 helped me find the gap, write the tests and check them; I reviewed the result.

[github-actions]

8 new or modified tests were run on 7 engines.

View workflow run

Test	Engine262	GraalJS	JavaScriptCore	QuickJS	SpiderMonkey	V8	XS
language/expressions/class/elements/syntax/early-errors/grammar-get-followed-by-name-on-next-line-without-parameters-error.js	❌	✅	✅	❌	✅	✅	❌
language/statements/class/elements/syntax/early-errors/grammar-get-followed-by-name-on-next-line-without-parameters-error.js	❌	✅	✅	❌	✅	✅	❌
language/statements/class/elements/syntax/valid/grammar-get-followed-by-name-on-next-line.js	❌	✅	✅	❌	✅	✅	✅
language/statements/class/elements/syntax/valid/grammar-method-name-followed-by-parameters-on-next-line.js	❌	✅	✅	✅	✅	✅	✅
language/statements/class/elements/syntax/valid/grammar-method-named-static.js	❌	✅	✅	❌	✅	✅	❌
language/statements/class/elements/syntax/valid/grammar-set-followed-by-name-on-next-line.js	❌	✅	✅	❌	✅	✅	✅
language/statements/class/elements/syntax/valid/grammar-static-followed-by-field-on-next-line.js	❌	✅	✅	✅	✅	✅	✅
language/statements/class/elements/syntax/valid/grammar-static-followed-by-method-on-next-line.js	❌	✅	✅	❌	✅	✅	✅

[hexbinoct]

The failures in the engine table are engine bugs, reproduced outside the harness with small snippets:

• Engine262 (all 8): ends a class element as a field whenever the next token is on a new line, and rejects a method named static. Fixed in fix: keep parsing a class element after a line terminator engine262/engine262#368.
• QuickJS (5): a line break after get or set ends the element, so get / a() {} becomes a field and a method, and static / () {} is a SyntaxError. Reported as Class elements are cut short after a line terminator following get, set or static bellard/quickjs#567.
• XS (2): static() {} is a SyntaxError (missing identifier), and get / a with no parameter list is accepted as a field a. Reported as A class method named static is a SyntaxError, and get followed by a line break and a name without parameters is accepted Moddable-OpenSource/moddable#1729.

V8, SpiderMonkey, JavaScriptCore and GraalJS pass all 8.