Cleanup of Register (informed by JET)

.github/workflows/benchmark.yml

@@ -33,7 +33,7 @@ jobs:
 
           let
               judgement = BenchmarkCI._loadjudge(BenchmarkCI.DEFAULT_WORKSPACE)
-              title = "JET Benchmark Result"
+              title = "Benchmark Result"
               ciresult = BenchmarkCI.CIResult(; judgement, title)
               BenchmarkCI.printcommentmd(stdout::IO, ciresult)
           end

CHANGELOG.md

@@ -1,8 +1,8 @@
 # News
 
-## v0.5.6 - dev
+## v0.5.6 - 2022-07-20
 
-- **(fix)** Bug-fixes to `PauliMeasurement` and `Reset`, detected by JET.
+- **(fix)** Bug-fixes to `PauliMeasurement`, `Reset`, and `Register`, detected by JET.
 
 ## v0.5.5 - 2022-07-05
 

src/classical_register.jl

@@ -6,6 +6,7 @@ struct Register{Tzv<:AbstractVector{UInt8},Tm<:AbstractMatrix{<:Unsigned}} <: Ab
 end
 
 Register(s,bits) = Register(MixedDestabilizer(s), bits)
+Register(s) = Register(s, Bool[])
 
 Base.copy(r::Register) = Register(copy(r.stab),copy(r.bits))
 
@@ -34,22 +35,27 @@ function apply!(r::Register, op::AbstractCliffordOperator, indices; kwargs...)
 end
 
 function apply!(r::Register, m::sMX{T}) where T
-    _, res = projectXrand!(quantumstate(r),m.qubit)
+    _, res = projectXrand!(r,m.qubit)
     T==Int && (bitview(r)[m.bit] = iszero(res))
     r
 end
 function apply!(r::Register, m::sMY{T}) where T
-    _, res = projectYrand!(quantumstate(r),m.qubit)
+    _, res = projectYrand!(r,m.qubit)
     T==Int && (bitview(r)[m.bit] = iszero(res))
     r
 end
 function apply!(r::Register, m::sMZ{T}) where T
-    _, res = projectZrand!(quantumstate(r),m.qubit)
+    _, res = projectZrand!(r,m.qubit)
     T==Int && (bitview(r)[m.bit] = iszero(res))
     r
 end
 function apply!(r::Register, m::PauliMeasurement{A,B,T}) where {A,B,T}
-    _, res = projectrand!(quantumstate(r),m.pauli)
+    _, res = projectrand!(r,m.pauli)
     T==Int && (bitview(r)[m.storagebit] = iszero(res))
     r
 end
+function projectrand!(r::Register, m)
+    q = quantumstate(r)
+    _, res = projectrand!(q,m)
+    r, res
+end

src/experimental/NoisyCircuits.jl

@@ -164,7 +164,7 @@ function QuantumClifford.apply!(s::AbstractStabilizer, mr::NoiseOp)
 end
 
 # TODO this one needs more testing
-function applywstatus!(s::AbstractStabilizer, v::VerifyOp) # XXX It assumes the other qubits are measured or traced out
+function applywstatus!(s::AbstractQCState, v::VerifyOp) # XXX It assumes the other qubits are measured or traced out
     # TODO QuantumClifford should implement some submatrix comparison
     canonicalize_rref!(quantumstate(s),v.indices) # Document why rref is used
     sv = stabilizerview(s)
@@ -374,7 +374,7 @@ end
 
 function applynoise_branches(state::Register, noise, indices; max_order=1)
     [(Register(newstate,copy(state.bits)), prob, order)
-     for (newstate, prob, order) in applynoise_branches(s, nop.noise, 1:n, max_order=max_order)]
+     for (newstate, prob, order) in applynoise_branches(state, noise, indices, max_order=max_order)]
 end
 
 # TODO tests for this

src/project_trace_reset.jl

@@ -578,7 +578,7 @@ See also: [`project!`](@ref), [`projectX!`](@ref), [`projectZrand!`](@ref), [`pr
 """
 function projectXrand!(state, qubit)
     _, anticom, res = projectX!(state, qubit)
-    anticom>0 && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
+    isnothing(res) && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
     return state, res
 end
 
@@ -593,7 +593,7 @@ See also: [`project!`](@ref), [`projectZ!`](@ref), [`projectXrand!`](@ref), [`pr
 """
 function projectZrand!(state, qubit)
     _, anticom, res = projectZ!(state, qubit)
-    anticom>0 && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
+    isnothing(res) && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
     return state, res
 end
 
@@ -608,7 +608,7 @@ See also: [`project!`](@ref), [`projectY!`](@ref), [`projectXrand!`](@ref), [`pr
 """
 function projectYrand!(state, qubit)
     _, anticom, res = projectY!(state, qubit)
-    anticom>0 && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
+    isnothing(res) && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
     return state, res
 end
 
@@ -623,7 +623,7 @@ See also: [`project!`](@ref), [`projectXrand!`](@ref), [`projectZrand!`](@ref),
 """
 function projectrand!(state, pauli)
     _, anticom, res = project!(state, pauli)
-    anticom>0 && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
+    isnothing(res) && (res = stabilizerview(state).phases[anticom] = rand((0x0, 0x2)))
     return state, res
 end
 

src/symbolic_cliffords.jl

@@ -69,7 +69,7 @@ macro qubitop1(name, kernel)
             q::Int
         end
         @doc $docstring $prefixname
-        @inline $(esc(:qubit_kernel))(::$prefixname, x, z) = $kernel 
+        @inline $(esc(:qubit_kernel))(::$prefixname, x, z) = $kernel
     end
 end
 
@@ -187,7 +187,7 @@ function CliffordOperator(op::SingleQubitOperator, n; compact=false)
         c = one(CliffordOperator, n)
         c[op.q,op.q] = op.xx, op.xz # TODO define an `embed` helper function
         c[n+op.q,op.q] = op.zx, op.zz
-        c.tab.phases[op.q] = op.px ? 0x2 : 0x0 # TODO define a `phasesview` or `phases` helper function 
+        c.tab.phases[op.q] = op.px ? 0x2 : 0x0 # TODO define a `phasesview` or `phases` helper function
         c.tab.phases[n+op.q] = op.pz ? 0x2 : 0x0
         return c
     end
@@ -247,7 +247,7 @@ macro qubitop2(name, kernel)
             q2::Int
         end
         @doc $docstring $prefixname
-        @inline $(esc(:qubit_kernel))(::$prefixname, x1, z1, x2, z2) = $kernel 
+        @inline $(esc(:qubit_kernel))(::$prefixname, x1, z1, x2, z2) = $kernel
     end
 end
 
@@ -266,7 +266,7 @@ function CliffordOperator(op::AbstractTwoQubitOperator, n; compact=false)
         for (i,q) in ((1,op.q1),(2,op.q2))
             c[q,q] = _c[i,i] # TODO define an `embed` helper function
             c[n+q,q] = _c[n+i,i]
-            c.tab.phases[q] = _c.tab.phases[i] # TODO define a `phasesview` or `phases` helper function 
+            c.tab.phases[q] = _c.tab.phases[i] # TODO define a `phasesview` or `phases` helper function
             c.tab.phases[n+q] = _c.tab.phases[n+i]
         end
         return c
@@ -374,4 +374,4 @@ project!(state::AbstractStabilizer, m::sMY) = projectY!(state, m.qubit)
 project!(state::AbstractStabilizer, m::sMZ) = projectZ!(state, m.qubit)
 projectrand!(state::AbstractStabilizer, m::sMX) = projectXrand!(state, m.qubit)
 projectrand!(state::AbstractStabilizer, m::sMY) = projectYrand!(state, m.qubit)
-projectrand!(state::AbstractStabilizer, m::sMZ) = projectZrand!(state, m.qubit)
+projectrand!(state::AbstractStabilizer, m::sMZ) = projectZrand!(state, m.qubit)