Deal with both old and new locations of Var of docplex (#1522)

* Deal with both old and new locations of Var

* add docplex version pin for macOS

qiskit/optimization/applications/ising/docplex.py

@@ -64,7 +64,13 @@
 import numpy as np
 from docplex.mp.constants import ComparisonType
 from docplex.mp.constr import LinearConstraint, QuadraticConstraint
-from docplex.mp.dvar import Var
+
+try:
+    # new location since docplex 2.16.196
+    from docplex.mp.dvar import Var
+except ImportError:
+    # old location until docplex 2.15.194
+    from docplex.mp.linear import Var
 from docplex.mp.model import Model
 from qiskit.quantum_info import Pauli
 

qiskit/optimization/problems/quadratic_program.py

@@ -24,7 +24,13 @@
 from docplex.mp.constr import (LinearConstraint as DocplexLinearConstraint,
                                QuadraticConstraint as DocplexQuadraticConstraint,
                                NotEqualConstraint)
-from docplex.mp.dvar import Var
+
+try:
+    # new location since docplex 2.16.196
+    from docplex.mp.dvar import Var
+except ImportError:
+    # old location until docplex 2.15.194
+    from docplex.mp.linear import Var
 from docplex.mp.model import Model
 from docplex.mp.model_reader import ModelReader
 from docplex.mp.quad import QuadExpr

requirements.txt

@@ -6,7 +6,8 @@ numpy>=1.17
 psutil>=5
 scikit-learn>=0.20.0
 dlx
-docplex
+docplex; sys_platform != 'darwin'
+docplex==2.15.194; sys_platform == 'darwin'
 fastdtw
 setuptools>=40.1.0
 h5py

setup.py

@@ -32,7 +32,8 @@
     "psutil>=5",
     "scikit-learn>=0.20.0",
     "dlx",
-    "docplex",
+    "docplex; sys_platform != 'darwin'",
+    "docplex==2.15.194; sys_platform == 'darwin'",
     "fastdtw",
     "setuptools>=40.1.0",
     "h5py",