Ignore bivariance in subtype relationship #41979
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…rameters, allow identical type parameter lists to merge in union signatures
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Rebuilt on top of #31023 which is an effective prerequisite to this being palatable |
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@typescript-bot test this |
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Heya @RyanCavanaugh, I've started to run the parallelized community code test suite on this PR at 7479b8a. You can monitor the build here. |
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Heya @RyanCavanaugh, I've started to run the extended test suite on this PR at 7479b8a. You can monitor the build here. |
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Heya @RyanCavanaugh, I've started to run the parallelized Definitely Typed test suite on this PR at 7479b8a. You can monitor the build here. |
| @@ -36,7 +36,7 @@ namespace ts { | |||
| return undefined; | |||
| } | |||
| else if (isArray(visited)) { | |||
| visitedNode = (lift || extractSingleNode)(visited); | |||
| visitedNode = (lift || extractSingleNode)(visited as unknown as NodeArray<Node>); | |||
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cc @weswigham @ahejlsberg interesting break here. visited is narrowed to Node[] here, but lift is undefined | (arg: NodeArray<Node>) => Node, so we were passing what we only proved to be a Node[] to something that needed a subtype of Node[]. It's not immediately clear to me if this is a bug-in-fact but it's definitely not correct per our normal definitions, i.e. you could not have written
if (lift) lift(visited);on this line
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The user suite test run you requested has finished and failed. I've opened a PR with the baseline diff from master. |
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Closing in favor of the more targeted fix |
Evaluates a potential fix for #41977