Display full function signature on hover for stack traces

[Steelskin]

Problem Statement

Stack traces display a truncated user-friendly string for the function used in a stack. While this trims down on the display, it can be really confusing to see which function is actually in use. This is especially true for closures or lambdas, which get truncated to "closure" or "lambda".

It would be very helpful to have the full original function name with arguments and closure/lambda reference on hover in the UI.

Solution Brainstorm

The trimming is done in trim_function_name in src/sentry/stacktraces/functions.py. I am unclear on how this connects to the UI for stack traces, though. Anyway, this is presumably where we "lose" the full function name.

Product Area

Dashboards

[getsantry]

Assigning to @getsentry/support for routing ⏲️

[getsantry]

Routing to @getsentry/product-owners-issues for triage ⏲️

[malwilley]

@Steelskin thanks for the feedback! To help us fully understand the issue, could you include some additional info?

• Which SDK are you using?
• What is your original function name, and what is shown in the UI?
• Is there a "better" trimmed value we could use in your example that would be more helpful?

[Steelskin]

I am not sure what you mean by SDK.

You can see examples in this PR where I am fixing a couple of issues with the current trimming function:

• closure #1 @Swift.MainActor () -> () in static Foo.CallFunction(args: [Swift.String]) -> () becomes #1 in the UI. I am fixing it to display closure in Foo.CallFunction instead.
• static Namespace.ThrowingFunction() throws -> Namespace.ExitValue? becomes throws in the UI. I am fixing it to display Namespace.ThrowingFunction instead.

Since we can't think of all possible ways the names are going to be mangled, this bug is about having the full original prototype on hover. This serves 2 purposes:

• Workaround for any future bug in trimming the function value.
• Have full diagnostic information related to closures. This is very handy when trying to diagnose a crash and figuring out which path was taken.

Does that answer your questions?