Correct checked_neg(unsigned(0))

armgong · Dec 5, 2015 · b30f184 · b30f184
1 parent 071390a
commit b30f184
Show file tree

Hide file tree

Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/base/int.jl b/base/int.jl
@@ -87,7 +87,10 @@ The overflow protection may impose a perceptible performance penalty.
 """
 function checked_neg end
 
-checked_neg(x::Unsigned) = throw(OverflowError())
+function checked_neg(x::Unsigned)
+    x != 0 && throw(OverflowError())
+    x
+end
 function checked_neg{T<:Union{Int8,Int16,Int32,Int64,Int128}}(x::T)
     x == typemin(T) && throw(OverflowError())
     -x

diff --git a/test/int.jl b/test/int.jl
@@ -129,6 +129,8 @@ import Base: checked_abs, checked_neg, checked_add, checked_sub, checked_mul
 for T in (Int8, Int16, Int32, Int64, Int128)
     # regular cases
     for s in (-1, +1)
+        @test checked_abs(T(0s)) === T(abs(0s))
+        @test checked_neg(T(0s)) === T(-(0s))
         @test checked_abs(T(3s)) === T(abs(3s))
         @test checked_neg(T(3s)) === T(-(3s))
         @test checked_abs(T(s*typemax(T))) === typemax(T)
@@ -194,6 +196,8 @@ end
 
 for T in (UInt8, UInt16, UInt32, UInt64, UInt128)
     # regular cases
+    @test checked_abs(T(0)) === T(0)
+    @test checked_neg(T(0)) === T(0)
     @test checked_abs(T(3)) === T(3)
     @test_throws OverflowError checked_neg(T(3))
     # regular cases