JSDoc: Infer return value of function

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Issue Type: Bug

Typescript works:

type Data = { a: string };

function test<T>(funct: (arg: Data) => T): T {
   return funct({a: 'test'});
}

test(a => a.a);  // return type: string => works OK

JSDoc bug:

/** @typedef {{ a: string }} Data */

/**
 * @template T
 * @param { (arg: Data) => T } funct 
 * @returns {T}
 */
function test(funct) {
   return funct({a: 'test'});
}

test((/** @type { Data } */ a) => a.a); // return type: string => works OK
test(a => a.a);                         // return type: any => not works - BUG

VS Code version: Code 1.55.2 (3c4e3df9e89829dce27b7b5c24508306b151f30d, 2021-04-13T09:36:32.643Z)
OS version: Darwin x64 20.3.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz (8 x 2700)
GPU Status	2d_canvas: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on protected_video_decode: unavailable_off rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled webgl: enabled webgl2: enabled
Load (avg)	2, 2, 2
Memory (System)	16.00GB (0.91GB free)
Process Argv	--crash-reporter-id 2e37b1f3-b89a-4c4c-8add-c119edc3cc5b --crash-reporter-id 2e37b1f3-b89a-4c4c-8add-c119edc3cc5b
Screen Reader	no
VM	0%

Extensions (17)

Extension	Author (truncated)	Version
vscode-openapi	42C	4.5.0
swagger-viewer	Arj	3.0.1
bracket-pair-colorizer-2	Coe	0.2.0
vscode-simpler-icons	dav	1.6.5
vscode-eslint	dba	2.1.20
gitlens	eam	11.4.1
EditorConfig	Edi	0.16.4
json-tools	eri	1.0.2
code-runner	for	0.11.3
jsdoc	lll	1.0.3
dotenv	mik	1.0.1
prettify-json	moh	0.0.3
vscode-typescript-tslint-plugin	ms-	1.3.3
vscode-yaml	red	0.18.0
sort-lines	Tyr	1.9.0
vscode-icons	vsc	11.4.0
html-css-class-completion	Zig	1.20.0

(3 theme extensions excluded)

A/B Experiments

vsliv368cf:30146710
vsreu685:30147344
python383cf:30185419
pythonvspyt678:30270856
pythonvspyt602cf:30294773
vspor879:30202332
vspor708:30202333
vspor363:30204092
vstry244:30276681
pythonvsnew554cf:30291488
pythontb:30283811
vspre833cf:30267465
pythonptprofiler:30281270
vscnewfilehidden:30294815
vshan820:30294714
pythondataviewer:30285071
vscus158:30286553

Start by reproducing the two TypeScript and JSDoc examples from the issue and compare the inferred return types for the unannotated callback. Trace the JSDoc generic callback inference path and add coverage for the failing example; done means the unannotated callback is inferred to return string rather than any.

Written by the indexing model from the issue text.

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