From b00fd9f4ab35247df0ee4ed987559f2fd52fcef7 Mon Sep 17 00:00:00 2001
From: Tommy Hofmann <thofma@gmail.com>
Date: Mon, 28 Aug 2023 10:45:02 +0200
Subject: [PATCH] Minor improvements (#1193)

---
 src/NumFieldOrd/NfOrd/Clgp/FacBase_Idl.jl |  2 +-
 src/NumFieldOrd/NfOrd/FracIdeal.jl        |  4 ++--
 src/NumFieldOrd/NfOrd/Ideal/Ideal.jl      |  4 ++--
 src/NumFieldOrd/NfOrd/NfOrd.jl            |  2 +-
 src/QuadForm/Quad/ZLattices.jl            | 14 +++++++++++---
 5 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/NumFieldOrd/NfOrd/Clgp/FacBase_Idl.jl b/src/NumFieldOrd/NfOrd/Clgp/FacBase_Idl.jl
index 32d68637ca..2ac850362d 100644
--- a/src/NumFieldOrd/NfOrd/Clgp/FacBase_Idl.jl
+++ b/src/NumFieldOrd/NfOrd/Clgp/FacBase_Idl.jl
@@ -29,7 +29,7 @@ function NfFactorBase(O::NfOrd, B::Int;
 end
 
 function NfFactorBase(O::NfOrd, lp::Vector{NfOrdIdl})
-  lp = sort(lp, lt = function(a,b) return norm(a) > norm(b); end)
+  lp = sort(lp, lt = function(a,b) return norm(a, copy = false) > norm(b, copy = false); end)
   FB = NfFactorBase()
   FB.size = length(lp)
   FB.ideals = lp
diff --git a/src/NumFieldOrd/NfOrd/FracIdeal.jl b/src/NumFieldOrd/NfOrd/FracIdeal.jl
index 30145c8e3f..d6e63b6429 100644
--- a/src/NumFieldOrd/NfOrd/FracIdeal.jl
+++ b/src/NumFieldOrd/NfOrd/FracIdeal.jl
@@ -280,9 +280,9 @@ end
 ################################################################################
 
 function Base.deepcopy_internal(x::NfAbsOrdFracIdl, dict::IdDict)
-  z = NfAbsOrdFracIdl(numerator(x), denominator(x))
+  z = NfAbsOrdFracIdl(numerator(x, copy = false), denominator(x, copy = false))
   if isdefined(x, :basis_matrix)
-    z.basis_matrix = deepcopy(x.basis_matrix)
+    z.basis_matrix = Base.deepcopy_internal(x.basis_matrix, dict)
   end
   return z
 end
diff --git a/src/NumFieldOrd/NfOrd/Ideal/Ideal.jl b/src/NumFieldOrd/NfOrd/Ideal/Ideal.jl
index 497f620f4f..e82b097092 100644
--- a/src/NumFieldOrd/NfOrd/Ideal/Ideal.jl
+++ b/src/NumFieldOrd/NfOrd/Ideal/Ideal.jl
@@ -294,12 +294,12 @@ Creates the ideal $(x, y)$ of $\mathcal O$.
 """
 function ideal(O::NfAbsOrd, x::ZZRingElem, y::NfAbsOrdElem)
   @assert parent(y) === O
-  return NfAbsOrdIdl(deepcopy(x), deepcopy(y))
+  return NfAbsOrdIdl(x, y)
 end
 
 function ideal(O::NfAbsOrd, x::Integer, y::NfAbsOrdElem)
   @assert parent(y) === O
-  return NfAbsOrdIdl(ZZRingElem(x), deepcopy(y))
+  return NfAbsOrdIdl(ZZRingElem(x), y)
 end
 
 function ideal(O::NfAbsOrd)
diff --git a/src/NumFieldOrd/NfOrd/NfOrd.jl b/src/NumFieldOrd/NfOrd/NfOrd.jl
index f77a92bae2..bd576c3a39 100644
--- a/src/NumFieldOrd/NfOrd/NfOrd.jl
+++ b/src/NumFieldOrd/NfOrd/NfOrd.jl
@@ -339,7 +339,7 @@ Assuming that the order $\mathcal O$ contains the equation order
 $\mathbf Z[\alpha]$ of the ambient number field, this function returns the
 index $[ \mathcal O : \mathbf Z]$.
 """
-function index(O::NfAbsOrd; copy::Bool = true)
+function index(O::NfAbsOrd; copy::Bool = false)
   if !isdefined(O, :index)
     i = gen_index(O)
     !isone(denominator(i)) && error("Order does not contain the equation order")
diff --git a/src/QuadForm/Quad/ZLattices.jl b/src/QuadForm/Quad/ZLattices.jl
index 3277406360..5e0b66f616 100644
--- a/src/QuadForm/Quad/ZLattices.jl
+++ b/src/QuadForm/Quad/ZLattices.jl
@@ -1363,6 +1363,16 @@ function Base.:(*)(L::ZZLat, a::RationalUnion)
   return a * L
 end
 
+################################################################################
+#
+#  Canonical basis matrix
+#
+################################################################################
+
+@attr FakeFmpqMat function _canonical_basis_matrix(L::ZZLat)
+  return hnf(FakeFmpqMat(basis_matrix(L)))
+end
+
 ################################################################################
 #
 #  Equality and hash
@@ -1379,9 +1389,7 @@ function Base.:(==)(L1::ZZLat, L2::ZZLat)
   if V1 != V2
     return false
   end
-  B1 = basis_matrix(L1)
-  B2 = basis_matrix(L2)
-  return hnf(FakeFmpqMat(B1)) == hnf(FakeFmpqMat(B2))
+  return _canonical_basis_matrix(L1) == _canonical_basis_matrix(L2)
 end
 
 function Base.hash(L::ZZLat, u::UInt)