Stop degree(::MPoly,...) from overflowing (#1524)

src/flint/fmpq_mpoly.jl

@@ -200,9 +200,13 @@ end
 function degree(a::QQMPolyRingElem, i::Int)
    n = nvars(parent(a))
    (i <= 0 || i > n) && error("Index must be between 1 and $n")
-   d = ccall((:fmpq_mpoly_degree_si, libflint), Int,
-             (Ref{QQMPolyRingElem}, Int, Ref{QQMPolyRing}), a, i - 1, a.parent)
-   return d
+   if degrees_fit_int(a)
+      d = ccall((:fmpq_mpoly_degree_si, libflint), Int,
+                (Ref{QQMPolyRingElem}, Int, Ref{QQMPolyRing}), a, i - 1, a.parent)
+      return d
+   else
+      return Int(degree_fmpz(a, i))
+   end
 end
 
 # Degree in the i-th variable as an ZZRingElem
@@ -225,6 +229,9 @@ end
 
 # Return an array of the max degrees in each variable
 function degrees(a::QQMPolyRingElem)
+   if !degrees_fit_int(a)
+      throw(OverflowError("degrees of polynomial do not fit into Int"))
+   end
    degs = Vector{Int}(undef, nvars(parent(a)))
    ccall((:fmpq_mpoly_degrees_si, libflint), Nothing,
          (Ptr{Int}, Ref{QQMPolyRingElem}, Ref{QQMPolyRing}),
@@ -254,6 +261,9 @@ function total_degree_fits_int(a::QQMPolyRingElem)
 
 # Total degree as an Int
 function total_degree(a::QQMPolyRingElem)
+   if !total_degree_fits_int(a)
+      throw(OverflowError("Total degree of polynomial does not fit into Int"))
+   end
    d = ccall((:fmpq_mpoly_total_degree_si, libflint), Int,
              (Ref{QQMPolyRingElem}, Ref{QQMPolyRing}), a, a.parent)
    return d

src/flint/fmpz_mod_mpoly.jl

@@ -208,10 +208,14 @@ end
 function degree(a::($etype), i::Int)
    n = nvars(parent(a))
    (i <= 0 || i > n) && error("Index must be between 1 and $n")
-   d = ccall((:fmpz_mod_mpoly_degree_si, libflint), Int,
+   if degrees_fit_int(a)
+      d = ccall((:fmpz_mod_mpoly_degree_si, libflint), Int,
              (Ref{($etype)}, Int, Ref{($rtype)}),
              a, i - 1, parent(a))
-   return d
+      return d
+   else
+      return Int(degree_fmpz(a, i))
+   end
 end
 
 # Degree in the i-th variable as an ZZRingElem
@@ -234,6 +238,9 @@ end
 
 # Return an array of the max degrees in each variable
 function degrees(a::($etype))
+   if !degrees_fit_int(a)
+      throw(OverflowError("degrees of polynomial do not fit into Int"))
+   end
    degs = Vector{Int}(undef, nvars(parent(a)))
    ccall((:fmpz_mod_mpoly_degrees_si, libflint), Nothing,
          (Ptr{Int}, Ref{($etype)}, Ref{($rtype)}),
@@ -263,6 +270,9 @@ end
 
 # Total degree as an Int
 function total_degree(a::($etype))
+   if !total_degree_fits_int(a)
+      throw(OverflowError("Total degree of polynomial does not fit into Int"))
+   end
    d = ccall((:fmpz_mod_mpoly_total_degree_si, libflint), Int,
              (Ref{($etype)}, Ref{($rtype)}),
              a, a.parent)

src/flint/fmpz_mpoly.jl

@@ -180,9 +180,13 @@ end
 function degree(a::ZZMPolyRingElem, i::Int)
    n = nvars(parent(a))
    (i <= 0 || i > n) && error("Index must be between 1 and $n")
-   d = ccall((:fmpz_mpoly_degree_si, libflint), Int,
-             (Ref{ZZMPolyRingElem}, Int, Ref{ZZMPolyRing}), a, i - 1, a.parent)
-   return d
+   if degrees_fit_int(a)
+      d = ccall((:fmpz_mpoly_degree_si, libflint), Int,
+                (Ref{ZZMPolyRingElem}, Int, Ref{ZZMPolyRing}), a, i - 1, a.parent)
+      return d
+   else
+      return Int(degree_fmpz(a, i))
+   end
 end
 
 # Degree in the i-th variable as an ZZRingElem
@@ -205,6 +209,9 @@ end
 
 # Return an array of the max degrees in each variable
 function degrees(a::ZZMPolyRingElem)
+   if !degrees_fit_int(a)
+      throw(OverflowError("degrees of polynomial do not fit into Int"))
+   end
    degs = Vector{Int}(undef, nvars(parent(a)))
    ccall((:fmpz_mpoly_degrees_si, libflint), Nothing,
          (Ptr{Int}, Ref{ZZMPolyRingElem}, Ref{ZZMPolyRing}),
@@ -234,6 +241,9 @@ function total_degree_fits_int(a::ZZMPolyRingElem)
 
 # Total degree as an Int
 function total_degree(a::ZZMPolyRingElem)
+   if !total_degree_fits_int(a)
+      throw(OverflowError("Total degree of polynomial does not fit into Int"))
+   end
    d = ccall((:fmpz_mpoly_total_degree_si, libflint), Int,
              (Ref{ZZMPolyRingElem}, Ref{ZZMPolyRing}), a, a.parent)
    return d

src/flint/fq_nmod_mpoly.jl

@@ -188,10 +188,14 @@ end
 function degree(a::fqPolyRepMPolyRingElem, i::Int)
    n = nvars(parent(a))
    !(1 <= i <= n) && error("Index must be between 1 and $n")
-   d = ccall((:fq_nmod_mpoly_degree_si, libflint), Int,
+   if degrees_fit_int(a)
+      d = ccall((:fq_nmod_mpoly_degree_si, libflint), Int,
              (Ref{fqPolyRepMPolyRingElem}, Int, Ref{fqPolyRepMPolyRing}),
              a, i - 1, a.parent)
-   return d
+      return d
+   else
+      return Int(degree_fmpz(a, i))
+   end
 end
 
 # Degree in the i-th variable as an ZZRingElem
@@ -215,6 +219,9 @@ end
 
 # Return an array of the max degrees in each variable
 function degrees(a::fqPolyRepMPolyRingElem)
+   if !degrees_fit_int(a)
+      throw(OverflowError("degrees of polynomial do not fit into Int"))
+   end
    degs = Vector{Int}(undef, nvars(parent(a)))
    ccall((:fq_nmod_mpoly_degrees_si, libflint), Nothing,
          (Ptr{Int}, Ref{fqPolyRepMPolyRingElem}, Ref{fqPolyRepMPolyRing}),
@@ -245,6 +252,9 @@ end
 
 # Total degree as an Int
 function total_degree(a::fqPolyRepMPolyRingElem)
+   if !total_degree_fits_int(a)
+      throw(OverflowError("Total degree of polynomial does not fit into Int"))
+   end
    d = ccall((:fq_nmod_mpoly_total_degree_si, libflint), Int,
              (Ref{fqPolyRepMPolyRingElem}, Ref{fqPolyRepMPolyRing}),
              a, a.parent)

src/flint/nmod_mpoly.jl

@@ -193,10 +193,13 @@ end
 function degree(a::($etype), i::Int)
    n = nvars(parent(a))
    (i <= 0 || i > n) && error("Index must be between 1 and $n")
-   d = ccall((:nmod_mpoly_degree_si, libflint), Int,
+   if degrees_fit_int(a)
+      d = ccall((:nmod_mpoly_degree_si, libflint), Int,
              (Ref{($etype)}, Int, Ref{($rtype)}),
              a, i - 1, parent(a))
-   return d
+   else
+      return Int(degree_fmpz(a, i))
+   end
 end
 
 # Degree in the i-th variable as an ZZRingElem
@@ -219,6 +222,9 @@ end
 
 # Return an array of the max degrees in each variable
 function degrees(a::($etype))
+   if !degrees_fit_int(a)
+      throw(OverflowError("degrees of polynomial do not fit into Int"))
+   end
    degs = Vector{Int}(undef, nvars(parent(a)))
    ccall((:nmod_mpoly_degrees_si, libflint), Nothing,
          (Ptr{Int}, Ref{($etype)}, Ref{($rtype)}),
@@ -248,6 +254,9 @@ end
 
 # Total degree as an Int
 function total_degree(a::($etype))
+   if !total_degree_fits_int(a)
+      throw(OverflowError("Total degree of polynomial does not fit into Int"))
+   end
    d = ccall((:nmod_mpoly_total_degree_si, libflint), Int,
              (Ref{($etype)}, Ref{($rtype)}),
              a, a.parent)

test/flint/fmpq_mpoly-test.jl

@@ -224,6 +224,12 @@ end
    @test trailing_coefficient(x) == 1
    @test trailing_coefficient(S(2)) == 2
    @test trailing_coefficient(S()) == 0
+
+   f = x^(ZZ(2)^100) * y^100
+   @test_throws InexactError degree(f, 1)
+   @test degree(f, 2) == 100
+   @test_throws OverflowError degrees(f)
+   @test_throws OverflowError total_degree(f)
 end
 
 @testset "QQMPolyRingElem.multivariate_coeff" begin

test/flint/fmpz_mpoly-test.jl

@@ -213,6 +213,12 @@ end
    @test trailing_coefficient(x) == 1
    @test trailing_coefficient(S(2)) == 2
    @test trailing_coefficient(S()) == 0
+
+   f = x^(ZZ(2)^100) * y^100
+   @test_throws InexactError degree(f, 1)
+   @test degree(f, 2) == 100
+   @test_throws OverflowError degrees(f)
+   @test_throws OverflowError total_degree(f)
 end
 
 @testset "ZZMPolyRingElem.multivariate_coeff" begin

test/flint/fq_nmod_mpoly-test.jl

@@ -241,6 +241,12 @@ end
    @test trailing_coefficient(x) == 1
    @test trailing_coefficient(S(2)) == 2
    @test trailing_coefficient(S()) == 0
+
+   f = x^(ZZ(2)^100) * y^100
+   @test_throws InexactError degree(f, 1)
+   @test degree(f, 2) == 100
+   @test_throws OverflowError degrees(f)
+   @test_throws OverflowError total_degree(f)
 end
 
 @testset "fqPolyRepMPolyRingElem.multivariate_coeff" begin

test/flint/gfp_fmpz_mpoly-test.jl

@@ -201,6 +201,12 @@ end
    @test trailing_coefficient(x) == 1
    @test trailing_coefficient(S(2)) == 2
    @test trailing_coefficient(S()) == 0
+
+   f = x^(ZZ(2)^100) * y^100
+   @test_throws InexactError degree(f, 1)
+   @test degree(f, 2) == 100
+   @test_throws OverflowError degrees(f)
+   @test_throws OverflowError total_degree(f)
 end
 
 @testset "FpMPolyRingElem.multivariate_coeff" begin

test/flint/nmod_mpoly-test.jl

@@ -241,6 +241,12 @@ end
    @test trailing_coefficient(x) == 1
    @test trailing_coefficient(S(2)) == 2
    @test trailing_coefficient(S()) == 0
+
+   f = x^(ZZ(2)^100) * y^100
+   @test_throws InexactError degree(f, 1)
+   @test degree(f, 2) == 100
+   @test_throws OverflowError degrees(f)
+   @test_throws OverflowError total_degree(f)
 end
 
 @testset "zzModMPolyRingElem.multivariate_coeff" begin