add read me

venv/lib/python3.12/site-packages/sympy/strategies/branch/tests/test_core.py

@@ -0,0 +1,117 @@
+from sympy.strategies.branch.core import (
+    exhaust, debug, multiplex, condition, notempty, chain, onaction, sfilter,
+    yieldify, do_one, identity)
+
+
+def posdec(x):
+    if x > 0:
+        yield x - 1
+    else:
+        yield x
+
+
+def branch5(x):
+    if 0 < x < 5:
+        yield x - 1
+    elif 5 < x < 10:
+        yield x + 1
+    elif x == 5:
+        yield x + 1
+        yield x - 1
+    else:
+        yield x
+
+
+def even(x):
+    return x % 2 == 0
+
+
+def inc(x):
+    yield x + 1
+
+
+def one_to_n(n):
+    yield from range(n)
+
+
+def test_exhaust():
+    brl = exhaust(branch5)
+    assert set(brl(3)) == {0}
+    assert set(brl(7)) == {10}
+    assert set(brl(5)) == {0, 10}
+
+
+def test_debug():
+    from io import StringIO
+    file = StringIO()
+    rl = debug(posdec, file)
+    list(rl(5))
+    log = file.getvalue()
+    file.close()
+
+    assert posdec.__name__ in log
+    assert '5' in log
+    assert '4' in log
+
+
+def test_multiplex():
+    brl = multiplex(posdec, branch5)
+    assert set(brl(3)) == {2}
+    assert set(brl(7)) == {6, 8}
+    assert set(brl(5)) == {4, 6}
+
+
+def test_condition():
+    brl = condition(even, branch5)
+    assert set(brl(4)) == set(branch5(4))
+    assert set(brl(5)) == set()
+
+
+def test_sfilter():
+    brl = sfilter(even, one_to_n)
+    assert set(brl(10)) == {0, 2, 4, 6, 8}
+
+
+def test_notempty():
+    def ident_if_even(x):
+        if even(x):
+            yield x
+
+    brl = notempty(ident_if_even)
+    assert set(brl(4)) == {4}
+    assert set(brl(5)) == {5}
+
+
+def test_chain():
+    assert list(chain()(2)) == [2]  # identity
+    assert list(chain(inc, inc)(2)) == [4]
+    assert list(chain(branch5, inc)(4)) == [4]
+    assert set(chain(branch5, inc)(5)) == {5, 7}
+    assert list(chain(inc, branch5)(5)) == [7]
+
+
+def test_onaction():
+    L = []
+
+    def record(fn, input, output):
+        L.append((input, output))
+
+    list(onaction(inc, record)(2))
+    assert L == [(2, 3)]
+
+    list(onaction(identity, record)(2))
+    assert L == [(2, 3)]
+
+
+def test_yieldify():
+    yinc = yieldify(lambda x: x + 1)
+    assert list(yinc(3)) == [4]
+
+
+def test_do_one():
+    def bad(expr):
+        raise ValueError
+
+    assert list(do_one(inc)(3)) == [4]
+    assert list(do_one(inc, bad)(3)) == [4]
+    assert list(do_one(inc, posdec)(3)) == [4]

venv/lib/python3.12/site-packages/sympy/strategies/branch/tests/test_tools.py

@@ -0,0 +1,42 @@
+from sympy.strategies.branch.tools import canon
+from sympy.core.basic import Basic
+from sympy.core.numbers import Integer
+from sympy.core.singleton import S
+
+
+def posdec(x):
+    if isinstance(x, Integer) and x > 0:
+        yield x - 1
+    else:
+        yield x
+
+
+def branch5(x):
+    if isinstance(x, Integer):
+        if 0 < x < 5:
+            yield x - 1
+        elif 5 < x < 10:
+            yield x + 1
+        elif x == 5:
+            yield x + 1
+            yield x - 1
+        else:
+            yield x
+
+
+def test_zero_ints():
+    expr = Basic(S(2), Basic(S(5), S(3)), S(8))
+    expected = {Basic(S(0), Basic(S(0), S(0)), S(0))}
+
+    brl = canon(posdec)
+    assert set(brl(expr)) == expected
+
+
+def test_split5():
+    expr = Basic(S(2), Basic(S(5), S(3)), S(8))
+    expected = {
+        Basic(S(0), Basic(S(0), S(0)), S(10)),
+        Basic(S(0), Basic(S(10), S(0)), S(10))}
+
+    brl = canon(branch5)
+    assert set(brl(expr)) == expected

venv/lib/python3.12/site-packages/sympy/strategies/branch/tests/test_traverse.py

@@ -0,0 +1,53 @@
+from sympy.core.basic import Basic
+from sympy.core.numbers import Integer
+from sympy.core.singleton import S
+from sympy.strategies.branch.traverse import top_down, sall
+from sympy.strategies.branch.core import do_one, identity
+
+
+def inc(x):
+    if isinstance(x, Integer):
+        yield x + 1
+
+
+def test_top_down_easy():
+    expr = Basic(S(1), S(2))
+    expected = Basic(S(2), S(3))
+    brl = top_down(inc)
+
+    assert set(brl(expr)) == {expected}
+
+
+def test_top_down_big_tree():
+    expr = Basic(S(1), Basic(S(2)), Basic(S(3), Basic(S(4)), S(5)))
+    expected = Basic(S(2), Basic(S(3)), Basic(S(4), Basic(S(5)), S(6)))
+    brl = top_down(inc)
+
+    assert set(brl(expr)) == {expected}
+
+
+def test_top_down_harder_function():
+    def split5(x):
+        if x == 5:
+            yield x - 1
+            yield x + 1
+
+    expr = Basic(Basic(S(5), S(6)), S(1))
+    expected = {Basic(Basic(S(4), S(6)), S(1)), Basic(Basic(S(6), S(6)), S(1))}
+    brl = top_down(split5)
+
+    assert set(brl(expr)) == expected
+
+
+def test_sall():
+    expr = Basic(S(1), S(2))
+    expected = Basic(S(2), S(3))
+    brl = sall(inc)
+
+    assert list(brl(expr)) == [expected]
+
+    expr = Basic(S(1), S(2), Basic(S(3), S(4)))
+    expected = Basic(S(2), S(3), Basic(S(3), S(4)))
+    brl = sall(do_one(inc, identity))
+
+    assert list(brl(expr)) == [expected]