DebuggerDisplay Stopwatch

[I-SER-I]

close #65724

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Issue Details

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close #65724

Author:	I-SER-I
Assignees:	-
Labels:	area-System.Diagnostics, community-contribution
Milestone:	-

[deeprobin]

@danmoseley Are tests for debugger displays required?

[danmoseley]

@danmoseley Are tests for debugger displays required?

yes, I've seen cases where a debugger display threw an exception, like any code. In fact, that's a good reason to put it in a private property like this, so it's easier to test.

@I-SER-I perhaps you could add a simple test that creates a Stopwatch, verifies (through reflection) that its DebuggerDisplay property string matches $"{sw.Elapsed} (IsRunning = {sw.IsRunning})", and maybe again with it started?

[stephentoub]

verifies (through reflection)

runtime/src/libraries/Common/tests/System/Diagnostics/DebuggerAttributes.cs

Line 113 in 7eaabea

internal static string ValidateDebuggerDisplayReferences(object obj)

e.g.

runtime/src/libraries/System.Linq/tests/GroupByTests.DebuggerAttributes.cs

Line 17 in 7eaabea

Assert.Equal($"Key = {keyString}", DebuggerAttributes.ValidateDebuggerDisplayReferences(grouping));

[I-SER-I]

@danmoseley, Could you help me where I need to implement DebuggerDisplayTest?
Because I didn't find a StopwatchTest

[I-SER-I]

@danmoseley, Could you help me where I need to implement DebuggerDisplayTest? Because I didn't find a StopwatchTest

@stephentoub )

[deeprobin]

@I-SER-I
I think you have to create a new test class in src/libraries/System.Runtime/tests with a test validating the result of the DebuggerDisplay.

[danmoseley]

Not sure how I didn't see the notification. Anyway, yes, what @deeprobin said. The reason the tests go there is that System.Runtime is where the type is exposed (https://github.com/dotnet/runtime/blob/4225cb0fff263e9fbc7ad007ab18e774a1b73d1e/src/libraries/System.Runtime/ref/System.Runtime.cs#L7345)

[danmoseley]

I'll add the test.

[danmoseley]

@steveisok any idea what's going on iwth the mono minjit lane?

[danmoseley]

The test has passed across wasm, devices, all OS, AOT... I think the failure of the whole minijit lane does not materially affect coverage.