Port: Allow line break before import attributes with keyword

[Copilot]

Port of microsoft/TypeScript#62593.

The parser rejected with import attributes when preceded by a line break, treating them as with statements instead. The hasPrecedingLineBreak() guard was incorrectly applied to both with and assert keywords, but should only apply to assert (which is context-sensitive and needs ASI protection).

import a
	from "./a.json"
	with {type: "json"}  // previously failed, parsed `with` as a statement

• Moved hasPrecedingLineBreak() check to only guard AssertKeyword in tryParseImportAttributes()

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[Copilot]

Pull request overview

Ports the TypeScript fix to allow with import attributes even when preceded by a line break, while keeping the ASI/line-break guard only for the context-sensitive assert keyword.

Changes:

• Adjusted tryParseImportAttributes() to apply hasPrecedingLineBreak() only to assert, not with
• Updated conformance baselines to reflect correct parsing/type/symbol output
• Removed prior error baselines that were produced by misparsing with as a statement

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

File	Description
internal/parser/parser.go	Updates the import-attributes detection logic to allow newline before with but not before assert.
testdata/baselines/reference/submodule/conformance/importAttributes11.types(.diff)	Updates type baselines to match the corrected parse.
testdata/baselines/reference/submodule/conformance/importAttributes11.symbols(.diff)	Updates symbol baselines consistent with import-attribute parsing.
testdata/baselines/reference/submodule/conformance/importAttributes11.errors.txt(.diff)	Removes baselines that existed due to the previous misparse/errors.

[Copilot]

This condition relies on operator precedence and mixed parentheses, which makes it easy to misread during future edits. Consider making the grouping explicit for both branches (e.g., parenthesize the with branch too, or split into two clear boolean vars) so it’s obvious that the line-break guard applies only to assert.

Suggested change

	if p.token == ast.KindWithKeyword || (p.token == ast.KindAssertKeyword && !p.hasPrecedingLineBreak()) {
	if (p.token == ast.KindWithKeyword) || (p.token == ast.KindAssertKeyword && !p.hasPrecedingLineBreak()) {

[Copilot]

This change intentionally preserves the line-break guard for assert while removing it for with. If there isn’t already a conformance/regression test that exercises assert preceded by a newline (ensuring it does not get parsed as import attributes due to ASI concerns), adding one alongside the updated with coverage would help prevent regressions.