Merge pull request #632 from JuliaSymbolics/fix-basicsymbolic-drop-metadata

Fix missing `metadata` when operation and resulting `BasicSymbolic` subtype mismatch

Author: bowenszhu

src/types.jl

@@ -588,13 +588,13 @@ function basicsymbolic(f, args, stype, metadata)
     elseif all(x->symtype(x) <: Number, args)
         if f === (+)
             res = +(args...)
-            if isadd(res)
+            if isadd(res) || isterm(res)
                 @set! res.metadata = metadata
             end
             res
         elseif f == (*)
             res = *(args...)
-            if ismul(res)
+            if ismul(res) || isterm(res)
                 @set! res.metadata = metadata
             end
             res

test/basics.jl

@@ -227,6 +227,21 @@ end
 
     # test that maketerm sets metadata correctly
     metadata = Base.ImmutableDict{DataType, Any}(Ctx1, "meta_1")
+    metadata2 = Base.ImmutableDict{DataType, Any}(Ctx2, "meta_2")
+    
+    d = b * c
+    @set! d.metadata = metadata2
+
+    s = SymbolicUtils.maketerm(typeof(a + d), +, [a, d], metadata)
+    @test isterm(s)
+    @test hasmetadata(s, Ctx1)
+    @test getmetadata(s, Ctx1) == "meta_1"
+
+    s = SymbolicUtils.maketerm(typeof(a * d), *, [a, d], metadata)
+    @test isterm(s)
+    @test hasmetadata(s, Ctx1)
+    @test getmetadata(s, Ctx1) == "meta_1"
+
     s = SymbolicUtils.maketerm(typeof(a^b), ^, [a * b, 3], metadata)
     @test !hasmetadata(s, Ctx1)