Fix issue 22038 - final switch error message should report all missing enum members

[dkorpel]

I added errorSupplemental to Statement so each missing member can be printed on its own line, for easy copy-pasting into your source code (assuming your text-editor does multi-line editing). I also merged the previous final switch test-cases into one appropriately named one to make it more organized. If that's not desirable, I can revert it, just trying out things.

[ibuclaw]

enum TOK has 235 members.

If I were to do:

final switch (tok)
{
    case TOK.null_:
        break;
}

The resultant compiler error would not be desirable.

[dkorpel]

Should I limit them to e.g. 10?

[thewilsonator]

I think the default is 6, or unlimited if -v(?) is passed. Take a look at the code that prints possible intended template matches.

[thewilsonator]

Ahh there it is

dmd/src/dmd/dtemplate.d

Line 5967 in 70482f4

const(uint) max_shown = !global.params.verbose ? 6 : uint.max;

copy that logic

[dkorpel]

I've done that now, but I don't know how to write a test for the verbose case since it puts absolute paths into the output, e.g.:

import    object	(/media/data1000/DebianHome/repos/dmd/test/../../druntime/import/object.d)
import    core.attribute	(/media/data1000/DebianHome/repos/dmd/test/../../druntime/import/core/attribute.d)

[MoonlightSentinel]

$p should help, see the README:

$p:<tail>$ paths ending with <tail> (which must refer to an existing file or directory)

EDIT: You could also filter those lines using TRANSFORM_OUTPUT: ... s.t. it also works for LDC

[dkorpel]

TRANSFORM_OUTPUT is better since I don't want the test to assert a specific order of semantic analysis. I'll steal the regex from fail15616b.d:

TRANSFORM_OUTPUT: remove_lines("^(predefs|binary|version|config|DFLAG|parse|import|semantic|entry|\s*$)")

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22038	enhancement	final switch error message should report all missing enum members

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#12709"

[ibuclaw]

Suggested change

	ss.errorSupplemental("... (%d more, -v to show) ...", missingMembers - maxShown);
	errorSupplemental(ss.loc, "... (%d more, -v to show) ...", missingMembers - maxShown);

There's nothing really gained from adding a new method.

[dkorpel]

Why do Statement.error and Expression.errorSupplemental exist then? My guess was it is structured this way to make it easier to replace with something pure later on or something, but I don't know what the idea behind error member functions is.

[RazvanN7]

The current error reporting system is archaic and should really be reworked to be cleaner and more flexible.

However, this is a different discussion. I suggest focusing on the minimal required changes for this PR.

[dkorpel]

I removed Statement.errorSupplemental now

[RazvanN7]

@dkorpel circleCI has been hanging for a day. maybe re-push to restart it.

[ibuclaw]

(Forcing restart of Azure pipelines).