Check for SymPy presence in unittary tests

[linpy.git] / tests / test_linear.py

diff --git a/tests/test_linear.py b/tests/test_linear.py
index 039ffc7..879cc17 100644 (file)
--- a/tests/test_linear.py
+++ b/tests/test_linear.py
@@ -1,4 +1,4 @@
-
+import functools
 import unittest
 
 from fractions import Fraction
@@ -6,6 +6,21 @@ from fractions import Fraction
 from pypol.linear import *
 
 
+try:
+    import sympy
+    def _with_sympy(func):
+        @functools.wraps(func)
+        def wrapper(self):
+            return func(self)
+        return wrapper
+except ImportError:
+    def _with_sympy(func):
+        @functools.wraps(func)
+        def wrapper(self):
+            raise unittest.SkipTest('SymPy is not available')
+        return wrapper
+
+
 class TestExpression(unittest.TestCase):
 
     def setUp(self):
@@ -83,13 +98,6 @@ class TestExpression(unittest.TestCase):
     def test_values(self):
         self.assertCountEqual(self.expr.values(), [1, -2, 3])
 
-    def test_symbol(self):
-        self.assertEqual(self.x.symbol, 'x')
-        with self.assertRaises(ValueError):
-            self.pi.symbol
-        with self.assertRaises(ValueError):
-            self.expr.symbol
-
     def test_issymbol(self):
         self.assertTrue(self.x.issymbol())
         self.assertFalse(self.pi.issymbol())
@@ -139,9 +147,9 @@ class TestExpression(unittest.TestCase):
     def test_repr(self):
         self.assertEqual(repr(self.x), "Symbol('x')")
         self.assertEqual(repr(self.one), 'Constant(1)')
+        self.assertEqual(repr(self.pi), 'Constant(22, 7)')
         self.assertEqual(repr(self.expr), "Expression({'x': 1, 'y': -2}, 3)")
 
-    @unittest.expectedFailure
     def test_fromstring(self):
         self.assertEqual(Expression.fromstring('x'), self.x)
         self.assertEqual(Expression.fromstring('-x'), -self.x)
@@ -159,10 +167,35 @@ class TestExpression(unittest.TestCase):
         self.assertEqual((self.x + self.y/2 + self.z/3)._toint(),
                 6*self.x + 3*self.y + 2*self.z)
 
+    @_with_sympy
+    def test_fromsympy(self):
+        sp_x, sp_y = sympy.symbols('x y')
+        self.assertEqual(Expression.fromsympy(sp_x), self.x)
+        self.assertEqual(Expression.fromsympy(sympy.Rational(22, 7)), self.pi)
+        self.assertEqual(Expression.fromsympy(sp_x - 2*sp_y + 3), self.expr)
+        with self.assertRaises(ValueError):
+            Expression.fromsympy(sp_x*sp_y)
+
+    @_with_sympy
+    def test_tosympy(self):
+        sp_x, sp_y = sympy.symbols('x y')
+        self.assertEqual(self.x.tosympy(), sp_x)
+        self.assertEqual(self.pi.tosympy(), sympy.Rational(22, 7))
+        self.assertEqual(self.expr.tosympy(), sp_x - 2*sp_y + 3)
+
 
 class TestConstant(unittest.TestCase):
 
-    pass
+    def setUp(self):
+        self.zero = Constant(0)
+        self.one = Constant(1)
+        self.pi = Constant(Fraction(22, 7))
+
+    @_with_sympy
+    def test_fromsympy(self):
+        self.assertEqual(Constant.fromsympy(sympy.Rational(22, 7)), self.pi)
+        with self.assertRaises(TypeError):
+            Constant.fromsympy(sympy.Symbol('x'))
 
 
 class TestSymbol(unittest.TestCase):
@@ -171,11 +204,25 @@ class TestSymbol(unittest.TestCase):
         self.x = Symbol('x')
         self.y = Symbol('y')
 
+    def test_name(self):
+        self.assertEqual(self.x.name, 'x')
+
     def test_symbols(self):
         self.assertListEqual(list(symbols('x y')), [self.x, self.y])
         self.assertListEqual(list(symbols('x,y')), [self.x, self.y])
         self.assertListEqual(list(symbols(['x', 'y'])), [self.x, self.y])
 
+    @_with_sympy
+    def test_fromsympy(self):
+        sp_x = sympy.Symbol('x')
+        self.assertEqual(Symbol.fromsympy(sp_x), self.x)
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(sympy.Rational(22, 7))
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(2 * sp_x)
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(sp_x*sp_x)
+
 
 class TestOperators(unittest.TestCase):