added tests

arrow/parser.py

@@ -128,7 +128,7 @@ def _generate_pattern_re(self, fmt):
         offset = 0
 
         # Extract the bracketed expressions to be reinserted later.
-        escaped_fmt = re.sub(self._ESCAPE_RE, "#" , fmt)
+        escaped_fmt = re.sub(self._ESCAPE_RE, "#", fmt)
         # Any number of S is the same as one.
         escaped_fmt = re.sub('S+', 'S', escaped_fmt)
         escaped_data = re.findall(self._ESCAPE_RE, fmt)

tests/parser_tests.py

@@ -59,6 +59,45 @@ def test_parse_token_invalid_meridians(self):
         self.parser._parse_token('a', 'p..m', parts)
         assertEqual(parts, {})
 
+    def test_parser_no_caching(self):
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_a').times(100)
+
+        self.parser = parser.DateTimeParser(cache_size=0)
+
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+
+    def test_parser_1_line_caching(self):
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_a').times(1)
+        self.parser = parser.DateTimeParser(cache_size=1)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_b').times(1)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+        self.parser._generate_pattern_re('fmt_b')
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_a').times(1)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+
+    def test_parser_multiple_line_caching(self):
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_a').times(1)
+        self.parser = parser.DateTimeParser(cache_size=2)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_b').times(1)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
+        self.parser._generate_pattern_re('fmt_b')
+
+        expect(parser.DateTimeParser._generate_pattern_re).args('fmt_a').times(0)
+        for _ in range(100):
+            self.parser._generate_pattern_re('fmt_a')
 
 
 class DateTimeParserParseTests(Chai):