fix ESCAPE_RE regular expression

src/solrq/__init__.py

@@ -54,7 +54,7 @@ class Value(object):
     """
 
     # note: since we escape spaces there is no need to escape AND, OR, NOT
-    ESCAPE_RE = re.compile(r'(?<!\\)(?P<char>[ &|+\-!(){}[\]*^"~?:])')
+    ESCAPE_RE = re.compile(r'(?<!\\)(?P<char>[ &|+\\\-!(){}[\]*^"~?:])')
     TIMEDELTA_FORMAT = "NOW{days:+d}DAYS{secs:+d}SECONDS{mills:+d}MILLISECONDS"
 
     def __init__(self, raw, safe=False):

tests/test_squery.py

@@ -192,19 +192,16 @@ def test_proximity():
     # ... but not if marked as safe
     assert str(Proximity("foo bar", 12, safe=True)) == '"foo bar"~12'
 
-    # note: boosting an explicit value has same result as raw string
-    assert str(
-        Proximity(Value("foo bar"), 12)
-    ) == str(
-        Proximity(Value("foo bar", safe=True), 12)
-    ) == '"foo\\ bar"~12'
-
     # note: only marking safe on all stages ensures it will not be escaped
     assert str(
         Proximity(Value("foo bar", safe=True), 12, safe=True)
     ) == '"foo bar"~12'
 
 
+def test_can_escape_special_characters():
+    assert str(Q(foo="\\")) == "foo:\\\\"
+
+
 def test_reprs():
     assert repr(Q(foo="bar"))
     assert repr(Value("foobar"))