make test cases for #48455 more reliable

xref: <#48455 (comment)>

Author: aviatesk

test/compiler/inline.jl

@@ -1921,11 +1921,17 @@ let src = code_typed1((Union{Bool,Tuple{String,Any}},)) do x
     @test any(iscall((src, f48397)), src.code)
 end
 g48397::Union{Bool,Tuple{String,Any}} = ("48397", 48397)
-@test_throws MethodError let
-    Base.Experimental.@force_compile
-    f48397(g48397)
+let res = @test_throws MethodError let
+        Base.Experimental.@force_compile
+        f48397(g48397)
+    end
+    err = res.value
+    @test err.f === f48397 && err.args === (g48397,)
 end
-@test_throws MethodError let
-    Base.Experimental.@force_compile
-    convert(Union{Bool,Tuple{String,String}}, g48397)
+let res = @test_throws MethodError let
+        Base.Experimental.@force_compile
+        convert(Union{Bool,Tuple{String,String}}, g48397)
+    end
+    err = res.value
+    @test err.f === convert && err.args === (Union{Bool,Tuple{String,String}}, g48397)
 end