Fix Issue 20530 - is(<...> == module/package) does not work with stri…

[BorisCarvajal]

…ng mixins

I made the fix more general (changing getDsymbol) just to try, so far no problem in dmd test suite.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20530	normal	is(<...> == module/package) does not work with string mixins

Testing this PR locally

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

dub fetch digger
dub run digger -- build "stable + dmd#10739"

[MoonlightSentinel]

[...] so far no problem in dmd test suite.

Because the test does only covers very few inputs of the trait. Some examples of the original test ( compilable/test16002.d) still don't work with this change:

alias a2 = mixin("imports.plainpackage");
alias b2 = mixin("imports.pkgmodule.plainmodule");

static assert(is(mixin("imports.plainpackage") == package));
static assert(is(mixin("a") == package));
static assert(is(a2 == package));
static assert(!is(mixin("imports.plainpackage.plainmodule") == package));
static assert(!is(mixin("b") == package));
static assert(!is(b2 == package));
// static assert(is(mixin("imports.pkgmodule") == package));  <= fails
static assert(!is(mixin("MyStruct") == package));

static assert(!is(mixin("imports.plainpackage") == module));
static assert(!is(mixin("a") == module));
static assert(is(mixin("imports.plainpackage.plainmodule") == module));
static assert(is(mixin("b") == module));

// static assert(is(mixin("imports.pkgmodule") == module)); // <= fails
static assert(!is(mixin("MyStruct") == module));

static assert(!is(mixin("imports.nonexistent") == package));
static assert(!is(mixin("imports.nonexistent") == module));

[BorisCarvajal]

Thanks for the info, I'm going to check.
The module/package implementation have some weird spots.