google / google/closure-compiler
`Array.reduce` method does not get type-checked correctly
- Dominant language
- JavaScript
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Description
`Array.reduce` method does not get type-checked correctly.
Eample:
```js
/**
* @type {Array}
*/
const arr = [1,2,3]
const sum = arr.reduce((a, b) => a + b, 0);
```
Raises these errors:
```
./src/js/index.js:12:12: ERROR - [JSC_UNKNOWN_EXPR_TYPE] could not determine the type of this expression
12| const sum = arr.reduce((a, b) => a + b, 0);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
./src/js/index.js:12:33: ERROR - [JSC_UNKNOWN_EXPR_TYPE] could not determine the type of this expression
12| const sum = arr.reduce((a, b) => a + b, 0);
^
```
Even though the callback parameters are obviously `number` and the result as well.
Compiler Version: v20221102
Build command:
```
java -jar ./scripts/closureCompiler.jar \
--entry_point=./src/js/index.js \
--js=./src/**.js \
--dependency_mode=PRUNE \
--warning_level=VERBOSE \
--js_output_file=./dist/bundle.js \
--module_resolution=WEBPACK \
--compilation_level=ADVANCED \
--jscomp_error=checkDebuggerStatement \
--jscomp_error=unusedLocalVariables \
--jscomp_error=reportUnknownTypes \
--jscomp_error=strictCheckTypes;
```
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