Add support for marking custom functions as deprecated with visual warnings by danvervlad · Pull Request #8156 · 4ian/GDevelop

danvervlad · 2026-01-21T14:59:11Z

Summary

Adds the ability to mark actions, conditions, and expressions as deprecated in extension functions
Displays visual deprecation warnings in the Events Sheet when deprecated functions are used
Allows extension authors to provide a deprecation message explaining what to use instead

Changes

Core/GDCore:

Added SetDeprecationMessage and IsDeprecated methods to InstructionMetadata, ExpressionMetadata, and MultipleInstructionMetadata
Added DeprecatedExpression error type to ExpressionParserError
Extended InstructionValidator with ValidateParameter that returns both validity and deprecation status via new ParameterValidationResult struct
Added deprecation fields to EventsFunction model (isDeprecated, deprecationMessage)

Events Sheet (UI):

Displays [DEPRECATED] prefix for deprecated actions and conditions
Shows deprecation message in tooltips
Highlights deprecated expressions with visual styling (background highlight)
Respects the existing showDeprecatedInstructionWarning preference flag

Extension Editor:

Added "Deprecated" checkbox in function properties
Added "Deprecation message" text field when function is marked deprecated

danvervlad · 2026-01-21T15:32:56Z

Function properties

With Deprecated = true

With Deprecated = false

With Show a warning on deprecated actions and conditions = true

In event sheet

In action/condition details

In expression details

With Show a warning on deprecated actions and conditions = false

In event sheet

In action/condition details

In expression details

danvervlad · 2026-01-21T15:42:05Z

In extension json, for serialization

4ian · 2026-01-26T23:12:35Z

Hello! Thanks for opening this PR.

The extension editor UI is still a bit rough today (the extension editor has changed a lot lately and we still try to improve it). The "Private" checkbox should have been named "Hidden": when you check it, you will see that existing usages of the function appear in yellow. So I wonder if this would have fitted your need?

More context: We try to make depreciation as transparent as possible for users. This means:

"Deprecated" functions are never removed from reviewed extensions to ensure compatibility with old projects
"Deprecated" functions are no longer visible to users when they add new actions, but the name of the new action is usually the same so they only notice that the list of parameter has changed

In your case, I guess you want to have the deprecation explanation shown to your users?
I will discuss this a bit more with the rest of the team.

danvervlad · 2026-02-03T15:59:45Z

Hello! Thanks for opening this PR.

The extension editor UI is still a bit rough today (the extension editor has changed a lot lately and we still try to improve it). The "Private" checkbox should have been named "Hidden": when you check it, you will see that existing usages of the function appear in yellow. So I wonder if this would have fitted your need?

More context: We try to make depreciation as transparent as possible for users. This means:

"Deprecated" functions are never removed from reviewed extensions to ensure compatibility with old projects

"Deprecated" functions are no longer visible to users when they add new actions, but the name of the new action is usually the same so they only notice that the list of parameter has changed

In your case, I guess you want to have the deprecation explanation shown to your users? I will discuss this a bit more with the rest of the team.

Hi, I know about the "Hidden" checkbox, but it's intended for use within the extension itself, isn't it?
The main idea for deprecated functions is that they should be clearly marked as such and highlighted everywhere (event sheets, detailed view) with a deprecation explanation, while being hidden from search results.

4ian · 2026-02-09T17:43:50Z

+            if (showDeprecatedInstructionWarning) {
+              hasDeprecationWarning = validationResult.hasDeprecationWarning();
+            }
+            validationResult.delete();


This will probably create a crash/memory corruption. Indeed, the JS/C++ bindings are using a [Value]:
[Value] ParameterValidationResult STATIC_ValidateParameter

This means (you can check that in glue.cpp, in the C function generated for interfacing) that the returned object is a static object in C++. There is always one living in memory, which is reused across calls. Which means:

Multiple calls will refer to the same object (the second call "erases" the first one)

If you delete it, you actually destroyed static memory which is basically undefined behavior I guess in C++/wasm. In short, it's a crash next time this memory is accessed.

This fix is simple: don't delete it :) This is sadly the hard to find/detect bugs with the C++/JS bindings (unclear lifetime of returned C++ objects).

Yes, you are right, removed delete call for static object

4ian · 2026-02-09T18:36:50Z

 };

 gd::String MetadataDeclarationHelper::GetFreeFunctionSentence(const gd::EventsFunction &eventsFunction) {
+  // Note: [DEPRECATED] prefix is now added in the UI layer (Instruction.js)


Do you think this note is useful? This seems like a detail for the reader of the code, this could be removed I think.

Agree, removed

4ian

Hi! I left a comment. My main other comment is that "[DEPRECATED]" is very "heavy" on the screen and I would rather have it as an additional preference (or we remove the existing preference and replace it by a preference which is an enum: "showDeprecatedOrHiddenWarning": "no" | "icon" | "icon-and-deprecated-warning-text").

Let me know if you can rework or introduce this preference :)

danvervlad · 2026-02-11T14:36:19Z

Hi @4ian, the idea sounds great! I've made appropriate changes, please take a look.

…Warning

During cherry-pick conflict resolution, the parameter validation logic was incorrectly changed from validateParameter() to isParameterValid(), which caused a TypeError when editing instructions. The validateParameter() method returns a validation result object with getType(), isValid(), and hasDeprecationWarning() methods, while isParameterValid() returns only a boolean. This broke the deprecation warning feature introduced in PR 4ian#8156 and caused errors when adding actions/conditions with expression parameters. Changes: - Restored validateParameter() usage instead of isParameterValid() - Added back hasDeprecationWarning variable and its calculation - Re-added DeprecatedParameterValue import and parameter - Fixed renderInlineParameter call to include hasDeprecationWarning Co-authored-by: Cursor <cursoragent@cursor.com>

danvervlad requested a review from 4ian as a code owner January 21, 2026 14:59

4ian reviewed Feb 9, 2026

View reviewed changes

danvervlad added 8 commits February 11, 2026 16:50

add IsDeprecated flag for action, conditions, expressions

68c8fa3

add DEPRECATED prefix for conditions and actions

f183447

add deprecation message, display in tooltip for actions and conditions

69533cc

add warn lable for deprecated actions and conditions in detailed view

ae583d4

add highlights and display deprecation message for expressions

f5b2adf

respect showDeprecatedInstructionWarning flag in settings

bb01d3c

refactor

97197aa

pr fixes: remove comment and delete call

0ba4e14

danvervlad force-pushed the feat/mark-function-as-deprecated branch from 767fcc1 to 81330bd Compare February 11, 2026 15:11

change showDeprecatedOrHiddenWarning to enum

a0277ab

danvervlad force-pushed the feat/mark-function-as-deprecated branch from 81330bd to a0277ab Compare February 11, 2026 15:11

danvervlad added 2 commits February 11, 2026 17:33

clean up comments

ac87559

update gdevelop-settings.yaml with enum for showDeprecatedInstruction…

b0f7e12

…Warning

danvervlad requested a review from 4ian February 11, 2026 16:32

4ian added 2 commits February 12, 2026 19:23

Merge branch 'master' into feat/mark-function-as-deprecated

d98ac2b

Fix type and formatting

b9a6719

4ian merged commit f1401b3 into 4ian:master Feb 12, 2026
1 of 3 checks passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add support for marking custom functions as deprecated with visual warnings#8156

Add support for marking custom functions as deprecated with visual warnings#8156
4ian merged 13 commits into4ian:masterfrom
danvervlad:feat/mark-function-as-deprecated

danvervlad commented Jan 21, 2026

Uh oh!

danvervlad commented Jan 21, 2026

Uh oh!

danvervlad commented Jan 21, 2026

Uh oh!

4ian commented Jan 26, 2026

Uh oh!

danvervlad commented Feb 3, 2026

Uh oh!

4ian Feb 9, 2026

Uh oh!

danvervlad Feb 11, 2026

Uh oh!

4ian Feb 9, 2026

Uh oh!

danvervlad Feb 11, 2026

Uh oh!

4ian left a comment

Uh oh!

danvervlad commented Feb 11, 2026 •

edited

Loading

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Conversation

danvervlad commented Jan 21, 2026

Summary

Changes

Uh oh!

danvervlad commented Jan 21, 2026

Function properties

With Deprecated = true

With Deprecated = false

With Show a warning on deprecated actions and conditions = true

In event sheet

In action/condition details

In expression details

With Show a warning on deprecated actions and conditions = false

In event sheet

In action/condition details

In expression details

Uh oh!

danvervlad commented Jan 21, 2026

Uh oh!

4ian commented Jan 26, 2026

Uh oh!

danvervlad commented Feb 3, 2026

Uh oh!

4ian Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

danvervlad Feb 11, 2026

Choose a reason for hiding this comment

Uh oh!

4ian Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

danvervlad Feb 11, 2026

Choose a reason for hiding this comment

Uh oh!

4ian left a comment

Choose a reason for hiding this comment

Uh oh!

danvervlad commented Feb 11, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

danvervlad commented Feb 11, 2026 •

edited

Loading