From c2285922c63384d1f0b840dc23e3a077bed5d6a0 Mon Sep 17 00:00:00 2001
From: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date: Aug 12 2018 14:02:02 +0000
Subject: First attempt


---

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c894537
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/.pytest_cache/
+*~
+*.py[co]
diff --git a/rustcfg/__init__.py b/rustcfg/__init__.py
new file mode 100644
index 0000000..dbdcd74
--- /dev/null
+++ b/rustcfg/__init__.py
@@ -0,0 +1,23 @@
+import string
+import pyparsing as pp
+from functools import lru_cache
+
+def paren_exp(keyword, contents):
+    return pp.Keyword(keyword)('op') + pp.Suppress('(') + contents('args') + pp.Suppress(')')
+
+@lru_cache()
+def cfg_grammar():
+    word = pp.Word(pp.alphanums + '_-')
+    exp = pp.Forward()
+
+    any_exp = paren_exp('any', pp.Group(pp.delimitedList(exp, delim=',')))
+    all_exp = paren_exp('all', pp.Group(pp.delimitedList(exp, delim=',')))
+    not_exp = paren_exp('not', exp)
+
+    exp << (any_exp | all_exp | not_exp | word)
+    exp.setName('expression')
+
+    cfg_exp = paren_exp('cfg', exp)
+
+    grammar = cfg_exp + pp.stringEnd()
+    return grammar
diff --git a/rustcfg/test/__init__.py b/rustcfg/test/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/rustcfg/test/__init__.py
diff --git a/rustcfg/test/test_expressions.py b/rustcfg/test/test_expressions.py
new file mode 100644
index 0000000..06800ed
--- /dev/null
+++ b/rustcfg/test/test_expressions.py
@@ -0,0 +1,37 @@
+import pytest
+import rustcfg
+
+"""
+"cfg(ok)", "cfg( ok )".parse::<Target>().unwrap().to_string());
+"foo-bar-baz", "foo-bar-baz".parse::<Target>().unwrap().to_string());
+"foo-bar-baz-quz", " foo-bar-baz-quz ".parse::<Target>().unwrap().to_string());
+"cfg(foo)", &Cfg::Is("foo".to_string()).to_string());
+"cfg(not(foo))", &Cfg::Not(Box::new(Cfg::Is("foo".to_string()))).to_string());
+"cfg(not(any(foo, bar)))
+"""
+
+testdata = [
+    ('cfg(ok)', True),
+    ('cfg( ok )', True),
+    ('cfg(foo-bar-bar)', True),
+    (' foo-bar-bar ', False),
+    (' cfg(not(foo))', True),
+    (' cfg(not(foo foo))', False),
+    ('cfg(any(asdf, asdf))', True),
+    ('cfg(all(asdf, asdf))', True),
+    ('cfg(any())', False),
+    ('cfg(all())', False),
+    ('cfg(all(not(asdf)))', True),
+    ('cfg(all(not(any(all(asdf)))))', True),
+]
+
+@pytest.mark.parametrize("expression,ok", testdata)
+def test_parsing(expression, ok):
+    g = rustcfg.cfg_grammar()
+    try:
+        t = g.parseString(expression)
+    except Exception:
+        good = False
+    else:
+        good = True
+    assert good == ok