pascals-triangle: update tests to canonical-date v1.2.0 (exercism#1164)

cmccandless · web-flow · commit 54c9694e31d9 · 2018-04-03T10:06:48.000-04:00
diff --git a/exercises/pascals-triangle/example.py b/exercises/pascals-triangle/example.py
@@ -1,14 +1,12 @@
-def triangle(nth):
-    return [row(i) for i in range(nth + 1)]
-
-
-def is_triangle(t):
-    new_t = triangle(len(t) - 1)
-    return t == new_t
-
-
-def row(nth):
-    r = [1]
-    for i in range(1, nth + 1):
-        r.append(int(r[-1] * (nth - i + 1) / i))
-    return " ".join([str(i) for i in r])
+def rows(row_count):
+    if row_count < 0:
+        return None
+    elif row_count == 0:
+        return []
+    r = []
+    for i in range(row_count):
+        rn = [1]
+        for j in range(i):
+            rn.append(sum(r[-1][j:j+2]))
+        r.append(rn)
+    return r
diff --git a/exercises/pascals-triangle/pascals_triangle.py b/exercises/pascals-triangle/pascals_triangle.py
@@ -1,10 +1,2 @@
-def triangle(row_count):
-    pass
-
-
-def is_triangle(triangle_rows_list):
-    pass
-
-
-def row(row_count):
+def rows(row_count):
     pass
diff --git a/exercises/pascals-triangle/pascals_triangle_test.py b/exercises/pascals-triangle/pascals_triangle_test.py
@@ -1,37 +1,51 @@
 import unittest
 
-from pascals_triangle import triangle, row, is_triangle
+from pascals_triangle import rows
+
+
+# Tests adapted from `problem-specifications//canonical-data.json` @ v1.2.0
+
+TRIANGLE = [
+    [1],
+    [1, 1],
+    [1, 2, 1],
+    [1, 3, 3, 1],
+    [1, 4, 6, 4, 1],
+    [1, 5, 10, 10, 5, 1],
+    [1, 6, 15, 20, 15, 6, 1],
+    [1, 7, 21, 35, 35, 21, 7, 1],
+    [1, 8, 28, 56, 70, 56, 28, 8, 1],
+    [1, 9, 36, 84, 126, 126, 84, 36, 9, 1]
+]
 
 
 class PascalsTriangleTest(unittest.TestCase):
-    def test_triangle1(self):
-        ans = ['1', '1 1', '1 2 1', '1 3 3 1', '1 4 6 4 1']
-        self.assertEqual(triangle(4), ans)
-
-    def test_triangle2(self):
-        ans = ['1', '1 1', '1 2 1', '1 3 3 1', '1 4 6 4 1', '1 5 10 10 5 1',
-               '1 6 15 20 15 6 1']
-        self.assertEqual(triangle(6), ans)
-
-    def test_is_triangle_true(self):
-        inp = ['1', '1 1', '1 2 1', '1 3 3 1', '1 4 6 4 1', '1 5 10 10 5 1']
-        self.assertIs(is_triangle(inp), True)
-
-    def test_is_triangle_false(self):
-        inp = ['1', '1 1', '1 2 1', '1 4 4 1']
-        self.assertIs(is_triangle(inp), False)
-
-    def test_row1(self):
-        ans = '1'
-        self.assertEqual(row(0), ans)
-
-    def test_row2(self):
-        ans = '1 2 1'
-        self.assertEqual(row(2), ans)
-
-    def test_row3(self):
-        ans = '1 7 21 35 35 21 7 1'
-        self.assertEqual(row(7), ans)
+    def test_zero_rows(self):
+        self.assertEqual(rows(0), [])
+
+    def test_single_row(self):
+        self.assertEqual(rows(1), TRIANGLE[:1])
+
+    def test_two_rows(self):
+        self.assertEqual(rows(2), TRIANGLE[:2])
+
+    def test_three_rows(self):
+        self.assertEqual(rows(3), TRIANGLE[:3])
+
+    def test_four_rows(self):
+        self.assertEqual(rows(4), TRIANGLE[:4])
+
+    def test_five_rows(self):
+        self.assertEqual(rows(5), TRIANGLE[:5])
+
+    def test_six_rows(self):
+        self.assertEqual(rows(6), TRIANGLE[:6])
+
+    def test_ten_rows(self):
+        self.assertEqual(rows(10), TRIANGLE[:10])
+
+    def test_negative_rows(self):
+        self.assertEqual(rows(-1), None)
 
 
 if __name__ == '__main__':
