DOCS: Fix changes to property output from source

[IgorSzyporyn]

Describe the bug
The new feature with removing pipes to present property types in a tag is a breaking change and will mangle function types as example

To Reproduce
Steps to reproduce the behavior:

1. Open any story that has an arrow function call as a property type
2. Click on Docs
3. Scroll down to description for this property
4. See error: (here using example for ref property in SvgIconProps from material ui)
   ((instance: SVGSVGElement null) => void)
RefObject<SVGSVGElement> null

Expected behavior
Expected to see: (here again using example for ref property in SvgIconProps from material ui)
((instance: SVGSVGElement | null) => void) React.RefObject<SVGSVGElement> null undefined

Screenshots

System:
OS: Windows 10 10.0.19041
CPU: (4) x64 Intel(R) Core(TM) i5-4460 CPU @ 3.20GHz
Binaries:
Node: 12.13.1 - C:\Program Files\nodejs\node.EXE
npm: 6.13.1 - ~\AppData\Roaming\npm\npm.CMD
Browsers:
Chrome: 84.0.4147.105
Edge: Spartan (44.19041.1.0)
npmPackages:
@storybook/addon-a11y: next => 6.0.0-rc.29
@storybook/addon-essentials: next => 6.0.0-rc.29
@storybook/addon-knobs: next => 6.0.0-rc.29
@storybook/addons: next => 6.0.0-rc.29
@storybook/api: next => 6.0.0-rc.29
@storybook/cli: next => 6.0.0-rc.29
@storybook/components: next => 6.0.0-rc.29
@storybook/core: next => 6.0.0-rc.29
@storybook/core-events: next => 6.0.0-rc.29
@storybook/react: next => 6.0.0-rc.29
@storybook/theming: next => 6.0.0-rc.29

[IgorSzyporyn]

Think I found the problem and solution

In the file: addons/docs/src/frameworks/angular/compodoc.ts
In the function: extractTypeFromValue (line 106)
Change: const valueType = typeof defaultValue into const valueType = typeof(defaultValue) (line 107)

In the file: addons/docs/src/frameworks/react/lib/defaultValues/createFromRawDefaultProp.ts
In the function: createDefaultValueFromRawDefaultProp (line 167)
Change: switch (typeof rawDefaultProp) { into switch (typeof(rawDefaultProp)) { (line 174)

Seems to be the only places - can it be right this is only supported for Angular and React?

[shilman]

Whoopee!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.0.20 containing PR #11868 that references this issue. Upgrade today to try it out!

Closing this issue. Please re-open if you think there's still more to do.