From 86f4694ed76aa23472f86be9c9e724ca18f9f55a Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Tue, 4 Nov 2025 04:26:04 +0000
Subject: [PATCH 1/9] Add @lencheck macro and tests (#188)

---
 src/utils.jl     | 18 ++++++++++++++++++
 test/lencheck.jl |  9 +++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 test/lencheck.jl

diff --git a/src/utils.jl b/src/utils.jl
index a98b54b..48989b4 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -6,6 +6,24 @@ import NLPModels.increment!, NLPModels.decrement!
 using JuMP, MathOptInterface
 const MOI = MathOptInterface
 
+"""
+    @lencheck expected expr
+
+Macro to check that `length(expr) == expected` at runtime.
+Throws an ArgumentError with a helpful message when the lengths mismatch.
+Example:
+    @lencheck nlp.meta.nvar x
+"""
+macro lencheck(expected, var)
+  return esc(:(begin
+    _len_expected = $(expected)
+    _len_var = length($(var))
+    if _len_var != _len_expected
+      throw(ArgumentError("length($(QuoteNode(var))) = $( _len_var ) but expected $( _len_expected )"))
+    end
+  end))
+end
+
 # VariableIndex
 const VI = MOI.VariableIndex  # VariableIndex(value)
 
diff --git a/test/lencheck.jl b/test/lencheck.jl
new file mode 100644
index 0000000..557eb39
--- /dev/null
+++ b/test/lencheck.jl
@@ -0,0 +1,9 @@
+using Test
+using NLPModelsJuMP
+
+@testset "lencheck macro" begin
+    x = [1,2,3]
+    @lencheck 3 x
+    y = [1,2]
+    @test_throws ArgumentError @lencheck 3 y
+end

From f880092d010b83c5cb7f9ea778c7f52c81a7ffc5 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Tue, 4 Nov 2025 09:58:00 +0530
Subject: [PATCH 2/9] Delete test/lencheck.jl

---
 test/lencheck.jl | 9 ---------
 1 file changed, 9 deletions(-)
 delete mode 100644 test/lencheck.jl

diff --git a/test/lencheck.jl b/test/lencheck.jl
deleted file mode 100644
index 557eb39..0000000
--- a/test/lencheck.jl
+++ /dev/null
@@ -1,9 +0,0 @@
-using Test
-using NLPModelsJuMP
-
-@testset "lencheck macro" begin
-    x = [1,2,3]
-    @lencheck 3 x
-    y = [1,2]
-    @test_throws ArgumentError @lencheck 3 y
-end

From 9358c02f30611e444d2f7deb3bc5964ca5ad1504 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Wed, 5 Nov 2025 14:16:35 +0000
Subject: [PATCH 3/9] Use NLPModels.@lencheck in cons and residual functions to
 validate input lengths (#188)

---
 src/moi_nlp_model.jl | 6 ++++++
 src/moi_nls_model.jl | 8 ++++++++
 test/lencheck.jl     | 9 +++++++++
 3 files changed, 23 insertions(+)
 create mode 100644 test/lencheck.jl

diff --git a/src/moi_nlp_model.jl b/src/moi_nlp_model.jl
index c85a7c0..6e74e5b 100644
--- a/src/moi_nlp_model.jl
+++ b/src/moi_nlp_model.jl
@@ -107,12 +107,16 @@ end
 
 function NLPModels.cons_lin!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_lin)
+  NLPModels.@lencheck nlp.meta.nvar x
+  NLPModels.@lencheck nlp.meta.nlin c
   coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   return c
 end
 
 function NLPModels.cons_nln!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_nln)
+  NLPModels.@lencheck nlp.meta.nvar x
+  NLPModels.@lencheck nlp.meta.nnln c
   if nlp.quadcon.nquad > 0
     for i = 1:(nlp.quadcon.nquad)
       qcon = nlp.quadcon.constraints[i]
@@ -127,6 +131,8 @@ end
 
 function NLPModels.cons!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons)
+  NLPModels.@lencheck nlp.meta.nvar x
+  NLPModels.@lencheck nlp.meta.ncon c
   if nlp.meta.nlin > 0
     coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   end
diff --git a/src/moi_nls_model.jl b/src/moi_nls_model.jl
index 8eeccf9..859109e 100644
--- a/src/moi_nls_model.jl
+++ b/src/moi_nls_model.jl
@@ -86,6 +86,8 @@ end
 
 function NLPModels.residual!(nls::MathOptNLSModel, x::AbstractVector, Fx::AbstractVector)
   increment!(nls, :neval_residual)
+  NLPModels.@lencheck nls.meta.nvar x
+  NLPModels.@lencheck nls.nls_meta.nequ Fx
   if nls.nls_meta.nlin > 0
     coo_prod!(
       nls.linequ.jacobian.rows,
@@ -253,12 +255,16 @@ end
 
 function NLPModels.cons_lin!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_lin)
+  NLPModels.@lencheck nls.meta.nvar x
+  NLPModels.@lencheck nls.nls_meta.nlin c
   coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   return c
 end
 
 function NLPModels.cons_nln!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_nln)
+  NLPModels.@lencheck nls.meta.nvar x
+  NLPModels.@lencheck nls.meta.nnln c
   if nls.quadcon.nquad > 0
     for i = 1:(nls.quadcon.nquad)
       qcon = nls.quadcon.constraints[i]
@@ -273,6 +279,8 @@ end
 
 function NLPModels.cons!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons)
+  NLPModels.@lencheck nls.meta.nvar x
+  NLPModels.@lencheck nls.meta.ncon c
   if nls.meta.nlin > 0
     coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   end
diff --git a/test/lencheck.jl b/test/lencheck.jl
new file mode 100644
index 0000000..2e8e09a
--- /dev/null
+++ b/test/lencheck.jl
@@ -0,0 +1,9 @@
+using Test
+using NLPModelsJuMP
+
+@testset "lencheck macro" begin
+    x = [1,2,3]
+    NLPModels.@lencheck 3 x
+    y = [1,2]
+    @test_throws ArgumentError NLPModels.@lencheck 3 y
+end

From 072123bf352c54f49f2e2a5999beaec3a09d0322 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Wed, 5 Nov 2025 14:16:47 +0000
Subject: [PATCH 4/9] changes

---
 src/utils.jl | 18 ------------------
 1 file changed, 18 deletions(-)

diff --git a/src/utils.jl b/src/utils.jl
index 48989b4..a98b54b 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -6,24 +6,6 @@ import NLPModels.increment!, NLPModels.decrement!
 using JuMP, MathOptInterface
 const MOI = MathOptInterface
 
-"""
-    @lencheck expected expr
-
-Macro to check that `length(expr) == expected` at runtime.
-Throws an ArgumentError with a helpful message when the lengths mismatch.
-Example:
-    @lencheck nlp.meta.nvar x
-"""
-macro lencheck(expected, var)
-  return esc(:(begin
-    _len_expected = $(expected)
-    _len_var = length($(var))
-    if _len_var != _len_expected
-      throw(ArgumentError("length($(QuoteNode(var))) = $( _len_var ) but expected $( _len_expected )"))
-    end
-  end))
-end
-
 # VariableIndex
 const VI = MOI.VariableIndex  # VariableIndex(value)
 

From a43abddf5c293dae8111af24e3e83c7dd51b7db4 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Wed, 5 Nov 2025 14:40:16 +0000
Subject: [PATCH 5/9] Use at-least length checks for output vectors (accept
 views/larger arrays)

---
 src/moi_nlp_model.jl | 12 +++++++++---
 src/moi_nls_model.jl | 12 +++++++++---
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/moi_nlp_model.jl b/src/moi_nlp_model.jl
index 6e74e5b..95a20b0 100644
--- a/src/moi_nlp_model.jl
+++ b/src/moi_nlp_model.jl
@@ -108,7 +108,9 @@ end
 function NLPModels.cons_lin!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_lin)
   NLPModels.@lencheck nlp.meta.nvar x
-  NLPModels.@lencheck nlp.meta.nlin c
+  if length(c) < nlp.meta.nlin
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.nlin)"))
+  end
   coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   return c
 end
@@ -116,7 +118,9 @@ end
 function NLPModels.cons_nln!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_nln)
   NLPModels.@lencheck nlp.meta.nvar x
-  NLPModels.@lencheck nlp.meta.nnln c
+  if length(c) < nlp.meta.nnln
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.nnln)"))
+  end
   if nlp.quadcon.nquad > 0
     for i = 1:(nlp.quadcon.nquad)
       qcon = nlp.quadcon.constraints[i]
@@ -132,7 +136,9 @@ end
 function NLPModels.cons!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons)
   NLPModels.@lencheck nlp.meta.nvar x
-  NLPModels.@lencheck nlp.meta.ncon c
+  if length(c) < nlp.meta.ncon
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.ncon)"))
+  end
   if nlp.meta.nlin > 0
     coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   end
diff --git a/src/moi_nls_model.jl b/src/moi_nls_model.jl
index 859109e..e948186 100644
--- a/src/moi_nls_model.jl
+++ b/src/moi_nls_model.jl
@@ -256,7 +256,9 @@ end
 function NLPModels.cons_lin!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_lin)
   NLPModels.@lencheck nls.meta.nvar x
-  NLPModels.@lencheck nls.nls_meta.nlin c
+  if length(c) < nls.nls_meta.nlin
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.nls_meta.nlin)"))
+  end
   coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   return c
 end
@@ -264,7 +266,9 @@ end
 function NLPModels.cons_nln!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_nln)
   NLPModels.@lencheck nls.meta.nvar x
-  NLPModels.@lencheck nls.meta.nnln c
+  if length(c) < nls.meta.nnln
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.meta.nnln)"))
+  end
   if nls.quadcon.nquad > 0
     for i = 1:(nls.quadcon.nquad)
       qcon = nls.quadcon.constraints[i]
@@ -280,7 +284,9 @@ end
 function NLPModels.cons!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons)
   NLPModels.@lencheck nls.meta.nvar x
-  NLPModels.@lencheck nls.meta.ncon c
+  if length(c) < nls.meta.ncon
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.meta.ncon)"))
+  end
   if nls.meta.nlin > 0
     coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   end

From 6dd690551d093b87015c6109e59c1fd5346909e1 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Wed, 5 Nov 2025 22:51:21 +0530
Subject: [PATCH 6/9] fixing the linear constraints computation in MOI NLS
 model

---
 src/moi_nls_model.jl | 14 +++++++++++---
 test/lencheck.jl     |  8 ++++----
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/moi_nls_model.jl b/src/moi_nls_model.jl
index e948186..5aeeb7d 100644
--- a/src/moi_nls_model.jl
+++ b/src/moi_nls_model.jl
@@ -256,10 +256,18 @@ end
 function NLPModels.cons_lin!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_lin)
   NLPModels.@lencheck nls.meta.nvar x
-  if length(c) < nls.nls_meta.nlin
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.nls_meta.nlin)"))
+  if (nls.nls_meta.nlin > 0) && (length(c) >= nls.nls_meta.nlin)
+    coo_prod!(nls.linequ.jacobian.rows, nls.linequ.jacobian.cols, nls.linequ.jacobian.vals, x, c)
+    if !isempty(nls.linequ.constants)
+      view(c, 1:length(nls.linequ.constants)) .+= nls.linequ.constants
+    end
+    return c
+  elseif length(c) >= nls.meta.nlin
+    coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
+    return c
+  else
+    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(min(nls.nls_meta.nlin, nls.meta.nlin))"))
   end
-  coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   return c
 end
 
diff --git a/test/lencheck.jl b/test/lencheck.jl
index 2e8e09a..e621343 100644
--- a/test/lencheck.jl
+++ b/test/lencheck.jl
@@ -2,8 +2,8 @@ using Test
 using NLPModelsJuMP
 
 @testset "lencheck macro" begin
-    x = [1,2,3]
-    NLPModels.@lencheck 3 x
-    y = [1,2]
-    @test_throws ArgumentError NLPModels.@lencheck 3 y
+  x = [1, 2, 3]
+  NLPModels.@lencheck 3 x
+  y = [1, 2]
+  @test_throws ArgumentError NLPModels.@lencheck 3 y
 end

From ee5a4f4b4ddd6f558e293b87e68d934dc63c6aa0 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Thu, 6 Nov 2025 10:25:44 +0530
Subject: [PATCH 7/9] Delete test/lencheck.jl

---
 test/lencheck.jl | 9 ---------
 1 file changed, 9 deletions(-)
 delete mode 100644 test/lencheck.jl

diff --git a/test/lencheck.jl b/test/lencheck.jl
deleted file mode 100644
index e621343..0000000
--- a/test/lencheck.jl
+++ /dev/null
@@ -1,9 +0,0 @@
-using Test
-using NLPModelsJuMP
-
-@testset "lencheck macro" begin
-  x = [1, 2, 3]
-  NLPModels.@lencheck 3 x
-  y = [1, 2]
-  @test_throws ArgumentError NLPModels.@lencheck 3 y
-end

From 1f41db08d749eae6072c3884fb7e22848654bea2 Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Thu, 6 Nov 2025 15:22:05 +0530
Subject: [PATCH 8/9] lencheck

---
 src/NLPModelsJuMP.jl |  2 ++
 src/moi_nlp_model.jl | 12 ------------
 src/moi_nls_model.jl | 24 +-----------------------
 3 files changed, 3 insertions(+), 35 deletions(-)

diff --git a/src/NLPModelsJuMP.jl b/src/NLPModelsJuMP.jl
index 5e72653..8795a6f 100644
--- a/src/NLPModelsJuMP.jl
+++ b/src/NLPModelsJuMP.jl
@@ -1,5 +1,7 @@
 module NLPModelsJuMP
 
+import NLPModels: @lencheck
+
 include("utils.jl")
 include("moi_nlp_model.jl")
 include("moi_nls_model.jl")
diff --git a/src/moi_nlp_model.jl b/src/moi_nlp_model.jl
index 95a20b0..c85a7c0 100644
--- a/src/moi_nlp_model.jl
+++ b/src/moi_nlp_model.jl
@@ -107,20 +107,12 @@ end
 
 function NLPModels.cons_lin!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_lin)
-  NLPModels.@lencheck nlp.meta.nvar x
-  if length(c) < nlp.meta.nlin
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.nlin)"))
-  end
   coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   return c
 end
 
 function NLPModels.cons_nln!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons_nln)
-  NLPModels.@lencheck nlp.meta.nvar x
-  if length(c) < nlp.meta.nnln
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.nnln)"))
-  end
   if nlp.quadcon.nquad > 0
     for i = 1:(nlp.quadcon.nquad)
       qcon = nlp.quadcon.constraints[i]
@@ -135,10 +127,6 @@ end
 
 function NLPModels.cons!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
   increment!(nlp, :neval_cons)
-  NLPModels.@lencheck nlp.meta.nvar x
-  if length(c) < nlp.meta.ncon
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nlp.meta.ncon)"))
-  end
   if nlp.meta.nlin > 0
     coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
   end
diff --git a/src/moi_nls_model.jl b/src/moi_nls_model.jl
index 5aeeb7d..8eeccf9 100644
--- a/src/moi_nls_model.jl
+++ b/src/moi_nls_model.jl
@@ -86,8 +86,6 @@ end
 
 function NLPModels.residual!(nls::MathOptNLSModel, x::AbstractVector, Fx::AbstractVector)
   increment!(nls, :neval_residual)
-  NLPModels.@lencheck nls.meta.nvar x
-  NLPModels.@lencheck nls.nls_meta.nequ Fx
   if nls.nls_meta.nlin > 0
     coo_prod!(
       nls.linequ.jacobian.rows,
@@ -255,28 +253,12 @@ end
 
 function NLPModels.cons_lin!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_lin)
-  NLPModels.@lencheck nls.meta.nvar x
-  if (nls.nls_meta.nlin > 0) && (length(c) >= nls.nls_meta.nlin)
-    coo_prod!(nls.linequ.jacobian.rows, nls.linequ.jacobian.cols, nls.linequ.jacobian.vals, x, c)
-    if !isempty(nls.linequ.constants)
-      view(c, 1:length(nls.linequ.constants)) .+= nls.linequ.constants
-    end
-    return c
-  elseif length(c) >= nls.meta.nlin
-    coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
-    return c
-  else
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(min(nls.nls_meta.nlin, nls.meta.nlin))"))
-  end
+  coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   return c
 end
 
 function NLPModels.cons_nln!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons_nln)
-  NLPModels.@lencheck nls.meta.nvar x
-  if length(c) < nls.meta.nnln
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.meta.nnln)"))
-  end
   if nls.quadcon.nquad > 0
     for i = 1:(nls.quadcon.nquad)
       qcon = nls.quadcon.constraints[i]
@@ -291,10 +273,6 @@ end
 
 function NLPModels.cons!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
   increment!(nls, :neval_cons)
-  NLPModels.@lencheck nls.meta.nvar x
-  if length(c) < nls.meta.ncon
-    throw(ArgumentError("length(c) = $(length(c)) but expected at least $(nls.meta.ncon)"))
-  end
   if nls.meta.nlin > 0
     coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   end

From e19bd3408157af49e217c9ec8b687817aa72147d Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoorarnav43@gmail.com>
Date: Fri, 7 Nov 2025 13:15:19 +0530
Subject: [PATCH 9/9] adding macro

---
 src/NLPModelsJuMP.jl |  1 +
 src/moi_nlp_model.jl |  8 ++++++++
 src/moi_nls_model.jl | 17 +++++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/src/NLPModelsJuMP.jl b/src/NLPModelsJuMP.jl
index 8795a6f..63d660c 100644
--- a/src/NLPModelsJuMP.jl
+++ b/src/NLPModelsJuMP.jl
@@ -1,6 +1,7 @@
 module NLPModelsJuMP
 
 import NLPModels: @lencheck
+export @lencheck
 
 include("utils.jl")
 include("moi_nlp_model.jl")
diff --git a/src/moi_nlp_model.jl b/src/moi_nlp_model.jl
index c85a7c0..d91e585 100644
--- a/src/moi_nlp_model.jl
+++ b/src/moi_nlp_model.jl
@@ -74,6 +74,7 @@ function nlp_model(moimodel::MOI.ModelLike; hessian::Bool = true, name::String =
 end
 
 function NLPModels.obj(nlp::MathOptNLPModel, x::AbstractVector)
+  @lencheck nlp.meta.nvar x
   increment!(nlp, :neval_obj)
   if nlp.obj.type == "LINEAR"
     res = dot(nlp.obj.gradient, x) + nlp.obj.constant
@@ -91,6 +92,7 @@ function NLPModels.obj(nlp::MathOptNLPModel, x::AbstractVector)
 end
 
 function NLPModels.grad!(nlp::MathOptNLPModel, x::AbstractVector, g::AbstractVector)
+  @lencheck nlp.meta.nvar x
   increment!(nlp, :neval_grad)
   if nlp.obj.type == "LINEAR"
     g .= nlp.obj.gradient
@@ -112,6 +114,8 @@ function NLPModels.cons_lin!(nlp::MathOptNLPModel, x::AbstractVector, c::Abstrac
 end
 
 function NLPModels.cons_nln!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
+  @lencheck nlp.meta.nvar x
+  @lencheck nlp.meta.nnln c
   increment!(nlp, :neval_cons_nln)
   if nlp.quadcon.nquad > 0
     for i = 1:(nlp.quadcon.nquad)
@@ -126,6 +130,8 @@ function NLPModels.cons_nln!(nlp::MathOptNLPModel, x::AbstractVector, c::Abstrac
 end
 
 function NLPModels.cons!(nlp::MathOptNLPModel, x::AbstractVector, c::AbstractVector)
+  @lencheck nlp.meta.nvar x
+  @lencheck nlp.meta.ncon c
   increment!(nlp, :neval_cons)
   if nlp.meta.nlin > 0
     coo_prod!(nlp.lincon.jacobian.rows, nlp.lincon.jacobian.cols, nlp.lincon.jacobian.vals, x, c)
@@ -213,6 +219,7 @@ function NLPModels.jac_structure!(
 end
 
 function NLPModels.jac_lin_coord!(nlp::MathOptNLPModel, x::AbstractVector, vals::AbstractVector)
+  @lencheck nlp.meta.nvar x
   increment!(nlp, :neval_jac_lin)
   index_lin = 1:(nlp.lincon.nnzj)
   view(vals, index_lin) .= nlp.lincon.jacobian.vals
@@ -220,6 +227,7 @@ function NLPModels.jac_lin_coord!(nlp::MathOptNLPModel, x::AbstractVector, vals:
 end
 
 function NLPModels.jac_nln_coord!(nlp::MathOptNLPModel, x::AbstractVector, vals::AbstractVector)
+  @lencheck nlp.meta.nvar x
   increment!(nlp, :neval_jac_nln)
   if nlp.quadcon.nquad > 0
     index = 0
diff --git a/src/moi_nls_model.jl b/src/moi_nls_model.jl
index 8eeccf9..a05fd31 100644
--- a/src/moi_nls_model.jl
+++ b/src/moi_nls_model.jl
@@ -85,6 +85,8 @@ function MathOptNLSModel(cmodel::JuMP.Model, F; hessian::Bool = true, name::Stri
 end
 
 function NLPModels.residual!(nls::MathOptNLSModel, x::AbstractVector, Fx::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
+  @lencheck nls.nls_meta.nequ Fx
   increment!(nls, :neval_residual)
   if nls.nls_meta.nlin > 0
     coo_prod!(
@@ -124,6 +126,7 @@ function NLPModels.jac_coord_residual!(
   x::AbstractVector,
   vals::AbstractVector,
 )
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_jac_residual)
   if nls.nls_meta.nlin > 0
     view(vals, 1:(nls.linequ.nnzj)) .= nls.linequ.jacobian.vals
@@ -144,6 +147,7 @@ function NLPModels.jprod_residual!(
   v::AbstractVector,
   Jv::AbstractVector,
 )
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_jprod_residual)
   nls.nls_meta.nlin > 0 && (Jv .= 0.0)
   if nls.nls_meta.nnln > 0
@@ -165,6 +169,7 @@ function NLPModels.jtprod_residual!(
   v::AbstractVector,
   Jtv::AbstractVector,
 )
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_jtprod_residual)
   nls.nls_meta.nlin > 0 && (Jtv .= 0.0)
   if nls.nls_meta.nnln > 0
@@ -198,6 +203,7 @@ function NLPModels.hess_coord_residual!(
   v::AbstractVector,
   vals::AbstractVector,
 )
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_hess_residual)
   if nls.nls_meta.nnln > 0
     MOI.eval_hessian_lagrangian(nls.Feval, vals, x, 0.0, view(v, nls.nls_meta.nln))
@@ -212,6 +218,7 @@ function NLPModels.hprod_residual!(
   v::AbstractVector,
   Hiv::AbstractVector,
 )
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_hprod_residual)
   if i ∈ nls.nls_meta.lin
     Hiv .= 0.0
@@ -224,6 +231,7 @@ function NLPModels.hprod_residual!(
 end
 
 function NLPModels.obj(nls::MathOptNLSModel, x::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_obj)
   obj = 0.0
   if nls.nls_meta.nnln > 0
@@ -239,6 +247,7 @@ function NLPModels.obj(nls::MathOptNLSModel, x::AbstractVector)
 end
 
 function NLPModels.grad!(nls::MathOptNLSModel, x::AbstractVector, g::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_grad)
   if nls.nls_meta.nnln > 0
     MOI.eval_objective_gradient(nls.ceval, g, x)
@@ -252,12 +261,16 @@ function NLPModels.grad!(nls::MathOptNLSModel, x::AbstractVector, g::AbstractVec
 end
 
 function NLPModels.cons_lin!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
+  @lencheck nls.meta.ncon c
   increment!(nls, :neval_cons_lin)
   coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
   return c
 end
 
 function NLPModels.cons_nln!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
+  @lencheck nls.meta.nnln c
   increment!(nls, :neval_cons_nln)
   if nls.quadcon.nquad > 0
     for i = 1:(nls.quadcon.nquad)
@@ -272,6 +285,8 @@ function NLPModels.cons_nln!(nls::MathOptNLSModel, x::AbstractVector, c::Abstrac
 end
 
 function NLPModels.cons!(nls::MathOptNLSModel, x::AbstractVector, c::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
+  @lencheck nls.meta.ncon c
   increment!(nls, :neval_cons)
   if nls.meta.nlin > 0
     coo_prod!(nls.lincon.jacobian.rows, nls.lincon.jacobian.cols, nls.lincon.jacobian.vals, x, c)
@@ -359,6 +374,7 @@ function NLPModels.jac_structure!(
 end
 
 function NLPModels.jac_lin_coord!(nls::MathOptNLSModel, x::AbstractVector, vals::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_jac_lin)
   index_lin = 1:(nls.lincon.nnzj)
   view(vals, index_lin) .= nls.lincon.jacobian.vals
@@ -366,6 +382,7 @@ function NLPModels.jac_lin_coord!(nls::MathOptNLSModel, x::AbstractVector, vals:
 end
 
 function NLPModels.jac_nln_coord!(nls::MathOptNLSModel, x::AbstractVector, vals::AbstractVector)
+  @lencheck nls.nls_meta.nvar x
   increment!(nls, :neval_jac_nln)
   if nls.quadcon.nquad > 0
     index = 0