Cleaner and faster linear expressions

[linpy.git] / pypol / tests / test_linexprs.py

diff --git a/pypol/tests/test_linexprs.py b/pypol/tests/test_linexprs.py
index a3e81b0..8dfd13e 100644 (file)
--- a/pypol/tests/test_linexprs.py
+++ b/pypol/tests/test_linexprs.py
@@ -4,29 +4,15 @@ import unittest
 from fractions import Fraction
 
 from ..linexprs import *
-
-
-try:
-    import sympy
-    def _requires_sympy(func):
-        @functools.wraps(func)
-        def wrapper(self):
-            return func(self)
-        return wrapper
-except ImportError:
-    def _requires_sympy(func):
-        @functools.wraps(func)
-        def wrapper(self):
-            raise unittest.SkipTest('SymPy is not available')
-        return wrapper
+from .libhelper import requires_sympy
 
 
 class TestExpression(unittest.TestCase):
 
     def setUp(self):
-        self.x = Expression({'x': 1})
-        self.y = Expression({'y': 1})
-        self.z = Expression({'z': 1})
+        self.x = Symbol('x')
+        self.y = Symbol('y')
+        self.z = Symbol('z')
         self.zero = Expression(constant=0)
         self.one = Expression(constant=1)
         self.pi = Expression(constant=Fraction(22, 7))
@@ -37,11 +23,10 @@ class TestExpression(unittest.TestCase):
         self.assertIsInstance(self.pi, Constant)
         self.assertNotIsInstance(self.x + self.pi, Symbol)
         self.assertNotIsInstance(self.x + self.pi, Constant)
-        xx = Expression({'x': 2})
+        xx = Expression({self.x: 2})
         self.assertNotIsInstance(xx, Symbol)
         with self.assertRaises(TypeError):
             Expression('x + y', 2)
-        self.assertEqual(Expression({'x': 2}), Expression({self.x: 2}))
         with self.assertRaises(TypeError):
             Expression({0: 2})
         with self.assertRaises(TypeError):
@@ -52,27 +37,29 @@ class TestExpression(unittest.TestCase):
             Expression(constant='a')
 
     def test_coefficient(self):
-        self.assertEqual(self.expr.coefficient('x'), 1)
-        self.assertEqual(self.expr.coefficient('y'), -2)
+        self.assertEqual(self.expr.coefficient(self.x), 1)
         self.assertEqual(self.expr.coefficient(self.y), -2)
-        self.assertEqual(self.expr.coefficient('z'), 0)
+        self.assertEqual(self.expr.coefficient(self.z), 0)
+        with self.assertRaises(TypeError):
+            self.expr.coefficients('x')
         with self.assertRaises(TypeError):
             self.expr.coefficient(0)
         with self.assertRaises(TypeError):
             self.expr.coefficient(self.expr)
 
     def test_getitem(self):
-        self.assertEqual(self.expr['x'], 1)
-        self.assertEqual(self.expr['y'], -2)
+        self.assertEqual(self.expr[self.x], 1)
         self.assertEqual(self.expr[self.y], -2)
-        self.assertEqual(self.expr['z'], 0)
+        self.assertEqual(self.expr[self.z], 0)
+        with self.assertRaises(TypeError):
+            self.assertEqual(self.expr['x'], 1)
         with self.assertRaises(TypeError):
             self.expr[0]
         with self.assertRaises(TypeError):
             self.expr[self.expr]
 
     def test_coefficients(self):
-        self.assertCountEqual(self.expr.coefficients(), [('x', 1), ('y', -2)])
+        self.assertCountEqual(self.expr.coefficients(), [(self.x, 1), (self.y, -2)])
 
     def test_constant(self):
         self.assertEqual(self.x.constant, 0)
@@ -80,9 +67,9 @@ class TestExpression(unittest.TestCase):
         self.assertEqual(self.expr.constant, 3)
 
     def test_symbols(self):
-        self.assertCountEqual(self.x.symbols, ['x'])
+        self.assertCountEqual(self.x.symbols, [self.x])
         self.assertCountEqual(self.pi.symbols, [])
-        self.assertCountEqual(self.expr.symbols, ['x', 'y'])
+        self.assertCountEqual(self.expr.symbols, [self.x, self.y])
 
     def test_dimension(self):
         self.assertEqual(self.x.dimension, 1)
@@ -141,21 +128,29 @@ class TestExpression(unittest.TestCase):
         self.assertNotEqual(self.x, self.y)
         self.assertEqual(self.zero, 0)
 
-    def test__toint(self):
-        self.assertEqual((self.x + self.y/2 + self.z/3)._toint(),
+    def test_scaleint(self):
+        self.assertEqual((self.x + self.y/2 + self.z/3).scaleint(),
                 6*self.x + 3*self.y + 2*self.z)
 
     def test_subs(self):
-        self.assertEqual(self.x.subs('x', 3), 3)
-        self.assertEqual(self.x.subs('x', self.x), self.x)
-        self.assertEqual(self.x.subs('x', self.y), self.y)
-        self.assertEqual(self.x.subs('x', self.x + self.y), self.x + self.y)
-        self.assertEqual(self.x.subs('y', 3), self.x)
-        self.assertEqual(self.pi.subs('x', 3), self.pi)
-        self.assertEqual(self.expr.subs('x', -3), -2 * self.y)
-        self.assertEqual(self.expr.subs([('x', self.y), ('y', self.x)]), 3 - self.x)
-        self.assertEqual(self.expr.subs({'x': self.y, 'y': self.x}), 3 - self.x)
-        self.assertEqual(self.expr.subs({self.x: self.z, self.y: self.z}), -self.z + 3)
+        self.assertEqual(self.x.subs(self.x, 3), 3)
+        self.assertEqual(self.x.subs(self.x, self.x), self.x)
+        self.assertEqual(self.x.subs(self.x, self.y), self.y)
+        self.assertEqual(self.x.subs(self.x, self.x + self.y), self.x + self.y)
+        self.assertEqual(self.x.subs(self.y, 3), self.x)
+        self.assertEqual(self.pi.subs(self.x, 3), self.pi)
+        self.assertEqual(self.expr.subs(self.x, -3), -2 * self.y)
+        self.assertEqual(self.expr.subs([(self.x, self.y), (self.y, self.x)]), 3 - self.x)
+        self.assertEqual(self.expr.subs({self.x: self.z, self.y: self.z}), 3 - self.z)
+        self.assertEqual(self.expr.subs({self.x: self.z, self.y: self.z}), 3 - self.z)
+        with self.assertRaises(TypeError):
+            self.x.subs('x', 3)
+        with self.assertRaises(TypeError):
+            self.expr.subs([('x', self.z), ('y', self.z)])
+        with self.assertRaises(TypeError):
+            self.expr.subs({'x': self.z, 'y': self.z})
+        with self.assertRaises(TypeError):
+            self.expr.subs(self.x, 'x')
 
     def test_fromstring(self):
         self.assertEqual(Expression.fromstring('x'), self.x)
@@ -165,22 +160,16 @@ class TestExpression(unittest.TestCase):
         self.assertEqual(Expression.fromstring('x - (3-1)y + 3'), self.expr)
         self.assertEqual(Expression.fromstring('x - 2*y + 3'), self.expr)
 
-    def test_str(self):
+    def test_repr(self):
         self.assertEqual(str(Expression()), '0')
         self.assertEqual(str(self.x), 'x')
         self.assertEqual(str(-self.x), '-x')
         self.assertEqual(str(self.pi), '22/7')
         self.assertEqual(str(self.expr), 'x - 2*y + 3')
 
-    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.x + self.one), "Expression('x + 1')")
-        self.assertEqual(repr(self.expr), "Expression('x - 2*y + 3')")
-
-    @_requires_sympy
+    @requires_sympy
     def test_fromsympy(self):
+        import sympy
         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)
@@ -188,8 +177,9 @@ class TestExpression(unittest.TestCase):
         with self.assertRaises(ValueError):
             Expression.fromsympy(sp_x*sp_y)
 
-    @_requires_sympy
+    @requires_sympy
     def test_tosympy(self):
+        import sympy
         sp_x, sp_y = sympy.symbols('x y')
         self.assertEqual(self.x.tosympy(), sp_x)
         self.assertEqual(self.pi.tosympy(), sympy.Rational(22, 7))
@@ -204,7 +194,8 @@ class TestSymbol(unittest.TestCase):
 
     def test_new(self):
         self.assertEqual(Symbol(' x '), self.x)
-        self.assertEqual(Symbol(self.x), self.x)
+        with self.assertRaises(TypeError):
+            Symbol(self.x)
         with self.assertRaises(TypeError):
             Symbol(1)
 
@@ -219,14 +210,12 @@ class TestSymbol(unittest.TestCase):
         with self.assertRaises(SyntaxError):
             Symbol.fromstring('1')
 
-    def test_str(self):
-        self.assertEqual(str(self.x), 'x')
-
     def test_repr(self):
-        self.assertEqual(repr(self.x), "Symbol('x')")
+        self.assertEqual(str(self.x), 'x')
 
-    @_requires_sympy
+    @requires_sympy
     def test_fromsympy(self):
+        import sympy
         sp_x = sympy.Symbol('x')
         self.assertEqual(Symbol.fromsympy(sp_x), self.x)
         with self.assertRaises(TypeError):
@@ -270,12 +259,13 @@ class TestConstant(unittest.TestCase):
             Constant.fromstring(1)
 
     def test_repr(self):
-        self.assertEqual(repr(self.zero), 'Constant(0)')
-        self.assertEqual(repr(self.one), 'Constant(1)')
-        self.assertEqual(repr(self.pi), 'Constant(22, 7)')
+        self.assertEqual(repr(self.zero), '0')
+        self.assertEqual(repr(self.one), '1')
+        self.assertEqual(repr(self.pi), '22/7')
 
-    @_requires_sympy
+    @requires_sympy
     def test_fromsympy(self):
+        import sympy
         self.assertEqual(Constant.fromsympy(sympy.Rational(22, 7)), self.pi)
         with self.assertRaises(TypeError):
             Constant.fromsympy(sympy.Symbol('x'))