Merge pull request #515 from JuliaSymbolics/s/fix-infinite-loop

apply arithmetic operations in basic_similarterm only if binary

Author: shashi

src/types.jl

@@ -532,7 +532,9 @@ function basic_similarterm(t, f, args, stype; metadata=nothing)
     if T === nothing
         T = _promote_symtype(f, args)
     end
-    if stype <: Number && (f in (+, *) || (f in (/, ^) && length(args) == 2)) && all(x->symtype(x) <: Number, args)
+    if T <: LiteralReal
+        Term{T}(f, args, metadata=metadata)
+    elseif stype <: Number && (f in (+, *) || (f in (/, ^) && length(args) == 2)) && all(x->symtype(x) <: Number, args)
         res = f(args...)
         if res isa Symbolic
             @set! res.metadata = metadata

test/rulesets.jl

@@ -54,6 +54,18 @@ end
     @test simplify(Term(zero, [x + 2])) == 0
 end
 
+@testset "LiteralReal" begin
+    @syms x1::LiteralReal x2::LiteralReal
+    s = cos(x1 * 3.2) - x2 * 5.8 + x2 * 1.2
+    @eqtest s == cos(x1 * 3.2) - x2 * 5.8 + x2 * 1.2
+
+    # Prevents automatic simplification:
+    @eqtest s != cos(3.2(x1^1)) - 4.6x2
+
+    # However, manual simplification should still work:
+    @eqtest simplify(s) == simplify(cos(3.2x1) - 4.6x2)
+end
+
 @testset "boolean" begin
     @syms a::Real b c