@deprecated strikethrough doesn't appear in many cases, such as JSX elements, const arrow functions, or properties.

[threehams]

TypeScript Version: 4.0.0-dev.20200701
VS Code Version: 1.47.0-insider commit: b16b467

Search Terms:
deprecated

Code

/** @deprecated */
type Props = {
  /** @deprecated */
  old: string,
  new: string,
}

/** @deprecated */
const Component = (props: Props) => <div />;

<Component old="old" new="new" />

/** @deprecated */
type Options = {
  /** @deprecated */
  old: string;
  new: string;
}

/** @deprecated */
const deprecatedFunction = (options: Options) => {}

deprecatedFunction({
  old: "",
  new: "hi",
});

Expected behavior:
All deprecated usages have strikethrough styles: <Component>, the old prop on Component, deprecatedFunction, old

Actual behavior:
Only props and options have strikethrough styles.

Playground Link:
Strikethrough isn't visible here, but ... is (just like stable VS Code vs. Insiders).
https://www.typescriptlang.org/play/?jsx=2&ts=4.0.0-beta&ssl=29&ssc=1&pln=1&pc=1#code/JYWwDg9gTgLgBAJQKYEMDG8BmUIjgIilQ3wG4AocgegCoa4ABAEyTCLRRiSbhqvJgBPMEjgAFHGADOcALxwA3uThxa9Zq3aduvfiogAbJgC44UmFGAA7AOYAaZXCtIA7qfOXbDgL6U1jFjYkDi4ePnI0CCtzOABhXEhnK3h5AAo2CGlTCUypAEo5AD44AB4mYAA3VUKKchL48CikZLhDJll8NvwnVw7nF26qQr86AM1g7TD+IRE4AHkwGGAomXklFX8NIJCdcP0jdwtrGwoVfsPPE-JfalGtrVDdCJX4QIfuADEAVysMZas5HBUpklitTAtQdECrJigobm8JqFvr9Ial1q0DgR8A4zq5TPgABbAbHXPIUIA

Related Issues:
None (feature is new to 4.0)

[Kingwl]

Thanks, I'll take a look

[threehams]

All of these show as deprecated in Intellisense suggestions, so something's definitely aware of them.

[Shinigami92]

Another case: TS Play

[ypresto]

One cause of this is because current implementation reports deprecation (calling addDeprecatedSuggestion()) for property access (from getPropertyTypeForIndexType()) but not for object literal passed to assignments, jsx attributes, or calls.

Maybe we can place addDeprecatedSuggestion() to some place in checkObjectLiteral() or its callees (or perhaps checkTypeRelatedToAndOptionallyElaborate() where assignability is tested.)

[ypresto]

Arrow function case is already resolved at least in TS 4.4.3.

[iliubinskii]

Have the same issue. Sample code:

f();

/**
 * @deprecated
 */
function f(): void {}

function x(): void {}

/**
 * @deprecated
 */
x.y = (): void => {};

x.y();

I get ts warning for "f();" but not for "x.y();"

[robsonvn]

Another example

[npalmius]

One more example here, although admittedly perhaps quite niche:

Since whole namespaces can be deprecated, and the hover-message shows the deprecation, I would expect it to be shown strikethrough.

[gund]

I did a little exploration of new TS 4.8 and found that it now tracks deprecations in node/symbol flags.
However it looks like it's unable to link PropertyAssignment symbol to original PropertySignature which is what happens when you declare a prop on typed object where the type has deprecated comment.
This does not happen when you access the prop later on which means that PropertyAccessExpression has a symbol that links to PropertySignature which has a deprecated flag set on it.

Here is a code example that I used.

Here are the screenshots:
Type definition has deprecated flag (on PropertySignature symbol):

And property declaration (nor it's identifier) does not (as they have their own PropertyAssignment symbol):

And then property access is marked with deprecated flag (via PropertySignature symbol):

So the potential fix could be to link PropertyAssignment symbol to original PropertySignature or at least to take deprecation flag from it.

[fbarbare]

Any updates on this? This would be quite usefull when working on a big shared code-base

[rattrayalex]

@RyanCavanaugh the lack of this feature influences library API design negatively. Could it be reconsidered for the next minor version?

Without a strikethrough for deprecated methods and parameters, I as a library designer (eg; the openai package) have incentive to hide deprecated things completely from the TS types or make them private, so that users don't inadvertently depend on deprecated functionality.

[BrainCrumbz]

We were looking for a solution as well and search pointed to this issue. Just to mention a test tried today on deprecated property in TS playground. When referencing the property from the object instance the property is correctly highlighted, as in:

userInfo.sex;

But when creating an object and filling the property, that is not highlighted:

const anotherInfo: AccountInfo = {
  ...
  sex: 'female',
}

Here's the link to playground.

[sandersn]

2025 Update: All the originally reported missing strikethroughs are resolved except for property assignments in object literals.

Edit: Unfortunately, the PR that adds the strikethrough there is too risky and has been untouched for 3 years, so it's not a viable fix.

[EKashpersky]

@sandersn can you share if this gets priority soon? Strikethrough really would help out in my current work prioritising development of new stuff in favour of deprecated, and further codebase refactoring.

[sandersn]

The team is unlikely to have time to look at this because we're busy porting to Go right now.