fix(jsx): correct source location when react-jsx and whitespace before jsx

[AviVahl]

the code seemed to be using node.pos (node.getFullStart()) instead of node.getStart(), which caused the source location to be off.

now baselines match babel's output (which seems correct).

not sure about using getTokenPosOfNode() (used by getStart()), but didn't find any better way to do things internally.

fixes #61533

[AviVahl]

I've applied the same fix for fragments as well, as they seemed to use the same pattern for source location handling.

[Copilot]

Pull request overview

This PR fixes incorrect source location information in JSX transformation when using react-jsx mode with whitespace before JSX elements. The issue was that the code was using node.pos (which includes leading trivia) instead of node.getStart() (which excludes leading trivia), causing column numbers in generated code to be off by the amount of leading whitespace.

Key changes:

• Updated visitJsxElement, visitJsxSelfClosingElement, and visitJsxFragment functions to use getTokenPosOfNode() for accurate source location
• All test baselines now show corrected column numbers that match Babel's output

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/compiler/transformers/jsx.ts	Modified JSX visitor functions to use getTokenPosOfNode() for correct source locations
tests/baselines/reference/tsxReactEmit8(jsx=react-jsxdev).js	Updated baseline with corrected line and column numbers
tests/baselines/reference/reactImportUnusedInNewJSXEmit(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxRuntimePragma(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxNamespaceNoElementChildrenAttributeReactJsx(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxNamespaceElementChildrenAttributeIgnoredWhenReactJsx(jsx=react-jsxdev).js	Updated baseline with corrected line and column numbers
tests/baselines/reference/jsxJsxsCjsTransformSubstitutesNamesFragment(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformSubstitutesNames(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformNestedSelfClosingChild(jsx=react-jsxdev).js	Updated baseline with corrected line and column numbers
tests/baselines/reference/jsxJsxsCjsTransformKeyPropCustomImportPragma(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformKeyPropCustomImport(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformKeyProp(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformCustomImportPragma(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformCustomImport(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxJsxsCjsTransformChildren(jsx=react-jsxdev).js	Updated baseline with corrected column numbers
tests/baselines/reference/jsxEmptyExpressionNotCountedAsChild(jsx=react-jsxdev).js	Updated baseline with corrected line and column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=legacy).js	Updated baseline with corrected column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=force).js	Updated baseline with corrected column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=system,moduledetection=auto).js	Updated baseline with corrected column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=legacy).js	Updated baseline with corrected column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=force).js	Updated baseline with corrected column numbers
tests/baselines/reference/commentsOnJSXExpressionsArePreserved(jsx=react-jsxdev,module=commonjs,moduledetection=auto).js	Updated baseline with corrected column numbers

[AviVahl]

rebased to latest main. accepted new baselines.

EDIT: and again, as main changed baselines an additional time.

[jakebailey]

LGTM but I would switch to skipTrivia instead.

[AviVahl]

Thank you. Been waiting for a while for this one to get in.
Btw, are you guys porting these PRs to typescript-go at some point? Are they being tracked?

[jakebailey]

Yes, there's a board, and Copilot is good at porting these. We have yet to start targeting 6.0 in the Go code, though, but that will happen ~today