Add tests based on Stefan Goessner's examples

See https://goessner.net/articles/JsonPath/index.html#e3

Author: kaapstorm

tests/test_examples.py

@@ -0,0 +1,74 @@
+import pytest
+
+from jsonpath_ng.ext.filter import Filter, Expression
+from jsonpath_ng.ext import parse
+from jsonpath_ng.jsonpath import *
+
+
+@pytest.mark.parametrize('string, parsed', [
+    # The authors of all books in the store
+    ("$.store.book[*].author",
+     Child(Child(Child(Child(Root(), Fields('store')), Fields('book')),
+                 Slice()), Fields('author'))),
+
+    # All authors
+    ("$..author", Descendants(Root(), Fields('author'))),
+
+    # All things in the store
+    ("$.store.*", Child(Child(Root(), Fields('store')), Fields('*'))),
+
+    # The price of everything in the store
+    ("$.store..price",
+     Descendants(Child(Root(), Fields('store')), Fields('price'))),
+
+    # The third book
+    ("$..book[2]",
+     Child(Descendants(Root(), Fields('book')),Index(2))),
+
+    # The last book in order
+    # ("$..book[(@.length-1)]",  # Not implemented
+    #  Child(Descendants(Root(), Fields('book')), Slice(start=-1))),
+    ("$..book[-1:]",
+     Child(Descendants(Root(), Fields('book')), Slice(start=-1))),
+
+    # The first two books
+    # ("$..book[0,1]",  # Not implemented
+    #  Child(Descendants(Root(), Fields('book')), Slice(end=2))),
+    ("$..book[:2]",
+     Child(Descendants(Root(), Fields('book')), Slice(end=2))),
+
+    # Filter all books with ISBN number
+    ("$..book[?(@.isbn)]",
+     Child(Descendants(Root(), Fields('book')),
+           Filter([Expression(Child(This(), Fields('isbn')), None, None)]))),
+
+    # Filter all books cheaper than 10
+    ("$..book[?(@.price<10)]",
+     Child(Descendants(Root(), Fields('book')),
+           Filter([Expression(Child(This(), Fields('price')), '<', 10)]))),
+
+    # All members of JSON structure
+    ("$..*", Descendants(Root(), Fields('*'))),
+])
+def test_goessner_examples(string, parsed):
+    """
+    Test Stefan Goessner's `examples`_
+
+    .. _examples: https://goessner.net/articles/JsonPath/index.html#e3
+    """
+    assert parse(string, debug=True) == parsed
+
+
+@pytest.mark.parametrize('string, parsed', [
+    # Navigate objects
+    ("$.store.book[0].title",
+     Child(Child(Child(Child(Root(), Fields('store')), Fields('book')),
+                 Index(0)), Fields('title'))),
+
+    # Navigate dictionaries
+    ("$['store']['book'][0]['title']",
+     Child(Child(Child(Child(Root(), Fields('store')), Fields('book')),
+                 Index(0)), Fields('title'))),
+])
+def test_obj_v_dict(string, parsed):
+    assert parse(string, debug=True) == parsed