fix(es/compat): Fix optional chaining #7530
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jridgewell
changed the title
kdy1
requested changes
Jun 17, 2023
swc-bot
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Jun 19, 2023
kdy1
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Jun 19, 2023
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Description:
This fixes a few bugs with optional chaining:
a?.c()a?.b.c()a.c?.()a.b.c?.()a?.b[c?.d]delete foo?.barfunction foo(a, b = a?.b) {}It also optimizes the AST for runtime evaluation. Before, we constructed a leftwards conditional tree (
(_a_b = (_a = a) == null ? void 0 : _a.b) == null ? void 0 : _a_b.c) instead of a rightward tree ((_a = a) == null ? void 0 : (_a_b = _a.b) == null ? void 0 : _a_b.c), which required multiple== nullchecks after the first nullish is found.BREAKING CHANGE:
Related issue (if exists):
Fixes #7531