From ebe20df76913a689e23c3156091877532cdd2a86 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 15:29:13 +0200
Subject: [PATCH 01/17] add assert False to see if triggered

---
 cpmpy/solvers/exact.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cpmpy/solvers/exact.py b/cpmpy/solvers/exact.py
index b2c09ea17..25ef29950 100644
--- a/cpmpy/solvers/exact.py
+++ b/cpmpy/solvers/exact.py
@@ -648,7 +648,8 @@ def get_core(self):
         return [self.assumption_dict[i][1] for i in self.xct_solver.getLastCore()]
     
     @classmethod
-    def mus_native(cls, soft, hard=[]):        
+    def mus_native(cls, soft, hard=[]):
+        assert False        
         # Create assumption variables and model with hard + (assumption -> soft)
         from cpmpy.tools.explain.utils import make_assump_model # avoid circular import
         m, soft, assumptions = make_assump_model(soft, hard)

From fcea9f049d5d021954aabeae7ed96635230f537c Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 15:34:10 +0200
Subject: [PATCH 02/17] add extra assert False

---
 tests/test_tools_mus.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 7e7ae1a1a..14f0392fc 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -24,6 +24,8 @@ def test_circular(self):
 
         assert set(self.mus_func(cons)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
+        assert False
+
 
     def test_bug_191(self):
         """

From 803bf1ee4a6bedf55dcd99b6d703a3dcf4176d44 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 15:41:08 +0200
Subject: [PATCH 03/17] remove extra assert False

---
 tests/test_tools_mus.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 14f0392fc..eeeba8976 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -24,7 +24,6 @@ def test_circular(self):
 
         assert set(self.mus_func(cons)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
-        assert False
 
 
     def test_bug_191(self):

From 74afac45fceaaff1c40335e311510b6160bf398b Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 15:56:27 +0200
Subject: [PATCH 04/17] add solver argument to mus tests to trigger testing
 with every solver

---
 tests/test_tools_mus.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index eeeba8976..a47f8f28c 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -10,7 +10,7 @@ def setup_method(self):
         self.mus_func = mus
         self.naive_func = mus_naive
 
-    def test_circular(self):
+    def test_circular(self, solver):
         x = cp.intvar(0, 3, shape=4, name="x")
         # circular "bigger then", UNSAT
         cons = [
@@ -25,8 +25,7 @@ def test_circular(self):
         assert set(self.mus_func(cons)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
 
-
-    def test_bug_191(self):
+    def test_bug_191(self, solver):
         """
         Original Bug request: https://github.com/CPMpy/cpmpy/issues/191
         When assum is a single boolvar and candidates is a list (of length 1), it fails.
@@ -40,7 +39,7 @@ def test_bug_191(self):
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_bug_191_many_soft(self):
+    def test_bug_191_many_soft(self, solver):
         """
         Checking whether bugfix 191  doesn't break anything in the MUS tool chain,
         when the number of soft constraints > 1.
@@ -58,7 +57,7 @@ def test_bug_191_many_soft(self):
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_wglobal(self):
+    def test_wglobal(self, solver):
         x = cp.intvar(-9, 9, name="x")
         y = cp.intvar(-9, 9, name="y")
 
@@ -86,7 +85,7 @@ def test_wglobal(self):
         # self.assertEqual(set(self.naive_func(cons)), set(cons[:2]))
 @pytest.mark.requires_solver("exact")       
 class TestNativeMusExact(TestMus):
-    def setup_method(self):
+    def setup_method(self, solver):
         self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver="exact")
         self.naive_func = mus_naive
 

From 2a1f4046cb34cd671393c207f46a48829894e5be Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 16:01:54 +0200
Subject: [PATCH 05/17] only add solver arg to native_mus test

---
 tests/test_tools_mus.py | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index a47f8f28c..23c949b3a 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -10,7 +10,7 @@ def setup_method(self):
         self.mus_func = mus
         self.naive_func = mus_naive
 
-    def test_circular(self, solver):
+    def test_circular(self):
         x = cp.intvar(0, 3, shape=4, name="x")
         # circular "bigger then", UNSAT
         cons = [
@@ -25,7 +25,7 @@ def test_circular(self, solver):
         assert set(self.mus_func(cons)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
 
-    def test_bug_191(self, solver):
+    def test_bug_191(self):
         """
         Original Bug request: https://github.com/CPMpy/cpmpy/issues/191
         When assum is a single boolvar and candidates is a list (of length 1), it fails.
@@ -39,7 +39,7 @@ def test_bug_191(self, solver):
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_bug_191_many_soft(self, solver):
+    def test_bug_191_many_soft(self):
         """
         Checking whether bugfix 191  doesn't break anything in the MUS tool chain,
         when the number of soft constraints > 1.
@@ -84,11 +84,12 @@ def test_wglobal(self, solver):
         assert not cp.Model(ms).solve()
         # self.assertEqual(set(self.naive_func(cons)), set(cons[:2]))
 @pytest.mark.requires_solver("exact")       
-class TestNativeMusExact(TestMus):
+class TestNativeMus(TestMus):
     def setup_method(self, solver):
-        self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver="exact")
-        self.naive_func = mus_naive
-
+        # solvers that implement native mus
+        if solver in ["exact"]:
+            self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
+            self.naive_func = mus_naive
 
 class TestQuickXplain(TestMus):
 

From 9ea94ec521a55a21639332b743761645965125e5 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 16:53:59 +0200
Subject: [PATCH 06/17] clean up

---
 tests/test_tools_mus.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 23c949b3a..7ad5e82b8 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -83,13 +83,13 @@ def test_wglobal(self, solver):
         assert len(ms) < len(cons)
         assert not cp.Model(ms).solve()
         # self.assertEqual(set(self.naive_func(cons)), set(cons[:2]))
+
+# add solvers that implement the native_mus method
 @pytest.mark.requires_solver("exact")       
 class TestNativeMus(TestMus):
     def setup_method(self, solver):
-        # solvers that implement native mus
-        if solver in ["exact"]:
-            self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
-            self.naive_func = mus_naive
+        self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
+        self.naive_func = mus_naive
 
 class TestQuickXplain(TestMus):
 

From 8ebbf6daba2c755704a6aba251acdd8fe2903162 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 16:54:32 +0200
Subject: [PATCH 07/17] remove assert False

---
 cpmpy/solvers/exact.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/cpmpy/solvers/exact.py b/cpmpy/solvers/exact.py
index 25ef29950..2a0401664 100644
--- a/cpmpy/solvers/exact.py
+++ b/cpmpy/solvers/exact.py
@@ -648,8 +648,7 @@ def get_core(self):
         return [self.assumption_dict[i][1] for i in self.xct_solver.getLastCore()]
     
     @classmethod
-    def mus_native(cls, soft, hard=[]):
-        assert False        
+    def mus_native(cls, soft, hard=[]):      
         # Create assumption variables and model with hard + (assumption -> soft)
         from cpmpy.tools.explain.utils import make_assump_model # avoid circular import
         m, soft, assumptions = make_assump_model(soft, hard)

From e54a39461c38213eb64d031c1330d489577cc4d0 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 16:57:06 +0200
Subject: [PATCH 08/17] clean up

---
 tests/test_tools_mus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 7ad5e82b8..fab864674 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -88,7 +88,7 @@ def test_wglobal(self, solver):
 @pytest.mark.requires_solver("exact")       
 class TestNativeMus(TestMus):
     def setup_method(self, solver):
-        self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
+        self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive
 
 class TestQuickXplain(TestMus):

From e41705ea1252510eb57d18ff3c948037a3a1d972 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 17:11:18 +0200
Subject: [PATCH 09/17] bugfix

---
 tests/test_tools_mus.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index fab864674..00f104943 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -87,6 +87,8 @@ def test_wglobal(self, solver):
 # add solvers that implement the native_mus method
 @pytest.mark.requires_solver("exact")       
 class TestNativeMus(TestMus):
+    # use solver from conftest.py
+    @pytest.fixture(autouse=True)
     def setup_method(self, solver):
         self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive

From 892faec6e3513021e92826670f0428571fd8fe9c Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 17:14:23 +0200
Subject: [PATCH 10/17] update

---
 tests/test_tools_mus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 00f104943..79588b6c6 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -89,7 +89,7 @@ def test_wglobal(self, solver):
 class TestNativeMus(TestMus):
     # use solver from conftest.py
     @pytest.fixture(autouse=True)
-    def setup_method(self, solver):
+    def setup_solver(self, solver):
         self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive
 

From 15d7fdeaf2e5a987d6223eb0cb908f84bb3489cc Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 17:26:58 +0200
Subject: [PATCH 11/17] final bugfix

---
 tests/test_tools_mus.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 79588b6c6..763748b83 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -34,7 +34,7 @@ def test_bug_191(self):
         hard = [~bv]
         soft = [bv]
 
-        mus_cons = self.mus_func(soft=soft, hard=hard, solver="ortools") # crashes
+        mus_cons = self.mus_func(soft=soft, hard=hard) # crashes
         assert set(mus_cons) == set(soft)
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
@@ -89,7 +89,7 @@ def test_wglobal(self, solver):
 class TestNativeMus(TestMus):
     # use solver from conftest.py
     @pytest.fixture(autouse=True)
-    def setup_solver(self, solver):
+    def setup_method(self, solver):
         self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive
 

From d79f6c36cb16b6cfa5415b504d69db9b72c96cf2 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 17:32:34 +0200
Subject: [PATCH 12/17] update

---
 tests/test_tools_mus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 763748b83..502758e05 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -57,7 +57,7 @@ def test_bug_191_many_soft(self):
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_wglobal(self, solver):
+    def test_wglobal(self):
         x = cp.intvar(-9, 9, name="x")
         y = cp.intvar(-9, 9, name="y")
 

From 4ba6605cc7cd0626cec478253cc397502cdd1a8f Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Fri, 24 Apr 2026 18:25:52 +0200
Subject: [PATCH 13/17] update comment

---
 tests/test_tools_mus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 502758e05..a734cca54 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -87,7 +87,7 @@ def test_wglobal(self):
 # add solvers that implement the native_mus method
 @pytest.mark.requires_solver("exact")       
 class TestNativeMus(TestMus):
-    # use solver from conftest.py
+    # use modern hook to add solver argument to setup method
     @pytest.fixture(autouse=True)
     def setup_method(self, solver):
         self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)

From 37da2820f5dadd541ff4bf36542187c4daec17d2 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Mon, 27 Apr 2026 11:45:32 +0200
Subject: [PATCH 14/17] remove autouse

---
 tests/test_tools_mus.py | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index a734cca54..8679b0657 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -4,7 +4,7 @@
 from cpmpy.tools import mss_opt, marco, OCUSException
 from cpmpy.tools.explain import mus, mus_naive, quickxplain, quickxplain_naive, optimal_mus, optimal_mus_naive, mss, mcs, ocus, ocus_naive, mus_native
 
-
+@pytest.mark.requires_solver("ortools")
 class TestMus:
     def setup_method(self):
         self.mus_func = mus
@@ -25,7 +25,7 @@ def test_circular(self):
         assert set(self.mus_func(cons)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
 
-    def test_bug_191(self):
+    def test_bug_191(self, solver):
         """
         Original Bug request: https://github.com/CPMpy/cpmpy/issues/191
         When assum is a single boolvar and candidates is a list (of length 1), it fails.
@@ -34,12 +34,12 @@ def test_bug_191(self):
         hard = [~bv]
         soft = [bv]
 
-        mus_cons = self.mus_func(soft=soft, hard=hard) # crashes
+        mus_cons = self.mus_func(soft=soft, hard=hard, solver=solver) # crashes
         assert set(mus_cons) == set(soft)
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_bug_191_many_soft(self):
+    def test_bug_191_many_soft(self, solver):
         """
         Checking whether bugfix 191  doesn't break anything in the MUS tool chain,
         when the number of soft constraints > 1.
@@ -52,12 +52,12 @@ def test_bug_191_many_soft(self):
             y == 4
         ]
 
-        mus_cons = self.mus_func(soft=soft, hard=hard) # crashes
+        mus_cons = self.mus_func(soft=soft, hard=hard, solver=solver) # crashes
         assert set(mus_cons) == set(soft)
         mus_naive_cons = self.naive_func(soft=soft, hard=hard) # crashes
         assert set(mus_naive_cons) == set(soft)
 
-    def test_wglobal(self):
+    def test_wglobal(self, solver):
         x = cp.intvar(-9, 9, name="x")
         y = cp.intvar(-9, 9, name="y")
 
@@ -76,7 +76,7 @@ def test_wglobal(self):
 
         # non-determinstic
         #self.assertEqual(set(mus(cons)), set(cons[1:3]))
-        ms = self.mus_func(cons)
+        ms = self.mus_func(cons, solver=solver)
         assert len(ms) < len(cons)
         assert not cp.Model(ms).solve()
         ms = self.naive_func(cons)
@@ -85,12 +85,10 @@ def test_wglobal(self):
         # self.assertEqual(set(self.naive_func(cons)), set(cons[:2]))
 
 # add solvers that implement the native_mus method
-@pytest.mark.requires_solver("exact")       
+@pytest.mark.requires_solver("exact", "gurobi")       
 class TestNativeMus(TestMus):
-    # use modern hook to add solver argument to setup method
-    @pytest.fixture(autouse=True)
-    def setup_method(self, solver):
-        self.mus_func = lambda soft, hard=[], solver=solver: mus_native(soft, hard=hard, solver=solver)
+    def setup_method(self):
+        self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive
 
 class TestQuickXplain(TestMus):

From 943037c4ad9b63783ca709a83219e818aa935074 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Mon, 27 Apr 2026 13:05:45 +0200
Subject: [PATCH 15/17] update

---
 tests/test_tools_mus.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 8679b0657..7707b16f3 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -10,7 +10,7 @@ def setup_method(self):
         self.mus_func = mus
         self.naive_func = mus_naive
 
-    def test_circular(self):
+    def test_circular(self, solver):
         x = cp.intvar(0, 3, shape=4, name="x")
         # circular "bigger then", UNSAT
         cons = [
@@ -22,7 +22,7 @@ def test_circular(self):
             (x[3] > x[1]).implies((x[3] > x[2]) & ((x[3] == 3) | (x[1] == x[2])))
         ]
 
-        assert set(self.mus_func(cons)) == set(cons[:3])
+        assert set(self.mus_func(cons, solver=solver)) == set(cons[:3])
         assert set(self.naive_func(cons)) == set(cons[:3])
 
     def test_bug_191(self, solver):

From 2c07e99783a2aaf844035da430f1a6638b57d6b6 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Mon, 27 Apr 2026 14:06:39 +0200
Subject: [PATCH 16/17] revert changes

---
 tests/test_tools_mus.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 0fc87d310..29b6bf63d 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -6,6 +6,7 @@
 
 @pytest.mark.requires_solver("ortools")
 class TestMus:
+    @pytest.fixture
     def setup_method(self):
         self.mus_func = mus
         self.naive_func = mus_naive
@@ -95,15 +96,13 @@ def test_decomposed_global(self, solver):
         assert len(set(mus_naive_cons)) == 1
         
 # add solvers that implement the native_mus method
-@pytest.mark.requires_solver("exact", "gurobi")       
+@pytest.mark.requires_solver("exact", "gurobi")
 class TestNativeMus(TestMus):
     def setup_method(self):
         self.mus_func = lambda soft, hard=[], solver="exact": mus_native(soft, hard=hard, solver=solver)
         self.naive_func = mus_naive
 
 
-
-
 class TestQuickXplain(TestMus):
 
     def setup_method(self):

From b28278d3a7d83fa3b212142d1fa40e408cf37b64 Mon Sep 17 00:00:00 2001
From: OrestisLomis <orestis.lomisg7@gmail.com>
Date: Mon, 27 Apr 2026 14:08:17 +0200
Subject: [PATCH 17/17] update

---
 tests/test_tools_mus.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/test_tools_mus.py b/tests/test_tools_mus.py
index 29b6bf63d..cb18ed9d1 100644
--- a/tests/test_tools_mus.py
+++ b/tests/test_tools_mus.py
@@ -6,7 +6,6 @@
 
 @pytest.mark.requires_solver("ortools")
 class TestMus:
-    @pytest.fixture
     def setup_method(self):
         self.mus_func = mus
         self.naive_func = mus_naive