Adding choco (#413)

* Creating branch and first tries

* add choco as choice

* Update choco.py

* canonical_comparison transformation

* new transformation used in linearize

* solve and most in post_constraint

* first version of post_constraint()

* all supported global constraints

* objective + solve()

* Update __init__.py

* Update utils.py

* corrections

* correct input to Choco

* solveall() + time_limit exception

* remove unsupported

* remove of only_bv_implies + add indomain + remove unneeded stuff

* fix finding optimal solution

* tests for choco

* cover all cases in tests

* forgotten skip

* remove unneeded checks + cover modulo extreme case

* only_bv_reifies

* reification + implications + correct transformations + cover cases for choco sytax

* remove part from only_bv_implies

* remove only_bv_implies test due to changes

* pychoco has a bug on finding all optimal solutions

* choco wants int and not np.int64

* correct solveAll count

* only_bv_reifies

* canonical comparison transformation

* choco 1 0 instead of True False

* only_implies

* minor

* minor

* minor

* choco docs

* style

* test_only_implies

* change order of transformations

* bring vars to left side in all cases

* handling True and False cases

* translate int to bool for bool variables

* minor

* fix count()

* np.array().tolist()

* polishing

* avoid flatten_objective

* cover case of list of vars in demand for cumulative

* to_var() + covering cases in input for constraints

* take all cases into account

* change order of transform

* cover case for sub

* time limit + finding all optimal solutions

* Move -IV (operator) correctly to lhs

* dealing with 'sub'

* dealing with sub

* canonical_comparison after flatten

* use is_boolexpr is stead of .is_bool

* cover all cases in min, max, abs

* fix count

* div and mod

* cover all cases for element

* Choco Exceptions

* checks in to_var and to_vars

* replicate code to to_var and to_vars

* Bounds and ints are int32 - checks

* ChocoTypeException

* use of is_int()

* convert numbers to int

* some from feedback

* ensure only_numexpr also works in reified

* ensure bv -> bv is not added twice

* update posting interface

* update with new interface

* add n_values constraint

* bounds are always int

* duration can be either var or int

* add Inverse to tests

* cleanup objective posting

* forgot import

* proper translation of status

* ensure always int when making constant_var

* rename and cleanup to_var

* added clarification why constraint can be None

* restructure and cleanup _get_constraint function

* exclude inverse from choco tests

* avoid creating too many vars

* minor fixes

* exclude inverse from Bool solvers

* change inverse tes

* typo

* fix mistake in implied cons

* fix choco tests

* Update test_constraints.py

* remove inverse test - separate PR

* remove inverse tests part 2

* add choco to github tests

---------

Co-authored-by: wout4 <wout.vanroose@gmail.com>
Co-authored-by: ignace <ignace.bleukx@kuleuven.be>

.github/workflows/python-test.yml

@@ -23,6 +23,7 @@ jobs:
           pip install z3-solver
           pip install exact
           pip install pysdd
+          pip install pychoco
           sudo snap install minizinc --classic
           pip install minizinc
       - name: Test with pytest

cpmpy/exceptions.py

@@ -17,6 +17,12 @@ class MinizincNameException(CPMpyException):
 class MinizincBoundsException(CPMpyException):
     pass
 
+class ChocoTypeException(CPMpyException):
+    pass
+
+class ChocoBoundsException(CPMpyException):
+    pass
+
 class NotSupportedError(CPMpyException):
     pass
 

cpmpy/solvers/__init__.py

@@ -18,6 +18,7 @@
         pysdd
         z3
         exact
+        choco
         utils
 
     ===============
@@ -33,6 +34,7 @@
         CPM_pysdd
         CPM_z3
         CPM_exact
+        CPM_choco
 
     =================
     List of functions
@@ -51,3 +53,5 @@
 from .pysdd import CPM_pysdd
 from .z3 import CPM_z3
 from .exact import CPM_exact
+from .choco import CPM_choco
+