Add checks for various other float formats.

Check for new stuff Go added in 1.13, and also
make sure leading 0s are permitted as some users
want to be able to do fixed-size output.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>

tests/openmetrics/test_parser.py

@@ -53,6 +53,22 @@ def test_float_gauge(self):
 """)
         self.assertEqual([GaugeMetricFamily("a", "help", value=1.2)], list(families))
 
+    def test_leading_zeros_simple_gauge(self):
+        families = text_string_to_metric_families("""# TYPE a gauge
+# HELP a help
+a 0000000000000000000000000000000000000000001
+# EOF
+""")
+        self.assertEqual([GaugeMetricFamily("a", "help", value=1)], list(families))
+
+    def test_leading_zeros_float_gauge(self):
+        families = text_string_to_metric_families("""# TYPE a gauge
+# HELP a help
+a 0000000000000000000000000000000000000000001.2e-1
+# EOF
+""")
+        self.assertEqual([GaugeMetricFamily("a", "help", value=.12)], list(families))
+
     def test_nan_gauge(self):
         families = text_string_to_metric_families("""# TYPE a gauge
 # HELP a help
@@ -610,14 +626,25 @@ def test_invalid_input(self):
             ('a  1\n# EOF\n'),
             ('a 1\t\n# EOF\n'),
             ('a 1 \n# EOF\n'),
+            ('a 1_2\n# EOF\n'),
+            ('a 0x1p-3\n# EOF\n'),
+            ('a 0x1P-3\n# EOF\n'),
+            ('a 0b1\n# EOF\n'),
+            ('a 0B1\n# EOF\n'),
+            ('a 0x1\n# EOF\n'),
+            ('a 0X1\n# EOF\n'),
+            ('a 0o1\n# EOF\n'),
+            ('a 0O1\n# EOF\n'),
             # Bad timestamp.
             ('a 1 z\n# EOF\n'),
             ('a 1 1z\n# EOF\n'),
+            ('a 1 1_2\n# EOF\n'),
             ('a 1 1.1.1\n# EOF\n'),
             ('a 1 NaN\n# EOF\n'),
             ('a 1 Inf\n# EOF\n'),
             ('a 1 +Inf\n# EOF\n'),
             ('a 1 -Inf\n# EOF\n'),
+            ('a 1 0x1p-3\n# EOF\n'),
             # Bad exemplars.
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 #\n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1# {} 1\n# EOF\n'),
@@ -627,6 +654,8 @@ def test_invalid_input(self):
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 1 1 \n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # '
              '{a="2345678901234567890123456789012345678901234567890123456789012345"} 1 1\n# EOF\n'),
+            ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 0x1p-3\n# EOF\n'),
+            ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 1 0x1p-3\n# EOF\n'),
             # Exemplars on unallowed samples.
             ('# TYPE a histogram\na_sum 1 # {a="b"} 0.5\n# EOF\n'),
             ('# TYPE a gaugehistogram\na_sum 1 # {a="b"} 0.5\n# EOF\n'),