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SAP / ui5-typescript

Tooling to enable TypeScript support in SAPUI5/OpenUI5 projects
https://sap.github.io/ui5-typescript
Apache License 2.0
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ts-interface-generator `Cannot read properties of undefined (reading 'getText')` #369

Closed dfenerski closed 2 years ago

dfenerski commented 2 years ago

During a migration of a JS library to TS format, I've ran the generator a couple of times to generate interfaces for controls as they were being migrated. Suddenly the generator started crashing with the same error: image

Adding --log-level "debug" gave me no useful information about the nature of the error, although I can add logs with the flag if it is necessary. Debugging also seemed a bit harsh, as one is limited to the compiled dist files, because this generator is not yet open-sourced as per my understanding.

Deleting node_modules and doing re-install had no effect.

Am I missing something?

akudev commented 2 years ago

@dfenerski The @ui5/ts-interface-generator (supporting control development in TypeScript), which you are apparently using here, is open-sourced. You can find the sources at https://github.com/SAP/ui5-typescript/tree/main/packages/ts-interface-generator and the line where the error appears to occur is here.

It's only the @ui5/dts-generator (generating type definitions for the UI5 JS libraries) which is outdated in this repository and where we still need to publish the current sources. I noticed the readme has not yet been adapted to the creation of the former and have adapted it now in https://github.com/SAP/ui5-typescript/commit/4727e99f1a949af66254aa7d473fc89a3c1b4bba - thanks!

The problem itself... I have to investigate (which might take a while due to UI5con happening this week). In general, this line of code looks at a metadata assignment which is supposed to look like

static readonly metadata = { ....

It seems to find something that is not as expected. Maybe something like

static readonly metadata;

If you want to have a look yourself, you can either set a breakpoint at https://github.com/SAP/ui5-typescript/blob/main/packages/ts-interface-generator/src/interfaceGenerationHelper.ts#L151 and check where metadata[0] lacks the "initializer" property or you can look for suspicious metadata definitions in the project sources.

dfenerski commented 2 years ago

It was indeed broken metadata on my part. Sorry for the inconvenience, thanks for the support and the insights! Looking forward to the UI5Con..

akudev commented 2 years ago

Thanks for checking!

In which way was it broken? It wouldn't hurt to give a more meaningful error message in such a situation to make the generator more robust..

dfenerski commented 2 years ago

The value provided to the metadata was recognized as it's 'type', due to being static readonly metadata: { ... instead of static readonly metadata = { .... It slipped past the syntax validation as technically it was valid. A copy-paste mistake caused by the migration of multiple controls at the same time.

akudev commented 2 years ago

@dfenerski the fix I just pushed recognizes a "metadata" member with no initialization and points this out in a warning. The class is then just ignored instead of crashing the generator. Thanks for describing the cause of the issue, so I could prevent others from running into the same problem!