chore: update parse5 to v7 #3602

divmain · 2023-06-30T07:01:35Z

Details

This upgrades parse5 from v6 to v7. Some things worth noting:

I found a bug in the template-expressions implementation during the upgrade. The fixture changes you see in the diff are the result of fixing the bug. There is one edge case that remains unresolved; I will open a work-item to address it as a follow-up, as it isn't related to the parse5 upgrade.
The upgrade from v6 to v7 is the largest breaking change in parse5's history. They ported to TypeScript, including some refactors of tracking internal logic.
Because parse5 internals were untyped prior to v6, we had our own types in place to provide some guard-rails. Those types are omitted, now that parse5 internals a typed.
Some of the type weirdness you see in the diff is there to work around methods and fields marked as private in parse5. They're present in the compiled JavaScript, but the type system complains without these workarounds.

...late-compiler/src/__tests__/fixtures/parsing-errors/forbidden-embed-tag/actual.html.disabled

...ate-compiler/src/__tests__/fixtures/expression-complex/valid/text-node-adjacency/expected.js

packages/@lwc/template-compiler/src/shared/parse5.ts

scripts/rollup/rollup.config.js

divmain · 2023-07-11T16:25:10Z

packages/@lwc/template-compiler/src/parser/expression-complex/types.ts

+export type Preprocessor = Omit<Parse5Preprocessor, 'pos'> & {
+    pos: number;
+    advance: () => void;
+};


Combine this with src/parser/expression-complex/html.ts?

packages/@lwc/template-compiler/src/parser/expression-complex/html.ts

divmain · 2023-07-11T16:35:28Z

packages/@lwc/template-compiler/src/parser/expression-complex/html.ts

        } else {
-            super.DATA_STATE(codePoint);
+            // @ts-ignore


Add a tracking issue for upstream private to protected.

This issue was fixed in inikulin/parse5#996. I can come back in a second PR and remove the type workarounds that are now redundant.

packages/@lwc/template-compiler/src/parser/expression-complex/html.ts

scripts/rollup/rollup.config.js

nolanlawson

LGTM, conditional +1 on a few things:

We figure out how <meta> and <embed> parsing changed, and if possible maintain the same behavior as before to avoid causing an observable change.
We wait until after CLCO for safety's sake.

# Conflicts: # packages/@lwc/template-compiler/package.json

divmain requested a review from a team as a code owner June 30, 2023 07:01

divmain marked this pull request as draft June 30, 2023 07:01

divmain force-pushed the divmain/upgrade-parse5 branch from 1ff2006 to 6cd54a7 Compare July 11, 2023 05:53