fix issue #172 compact JSON no longer parsing

This was quite intrusive, because loosing the tests surrounding the colon
made flow style lists with ::vector as key fail. Had to keept track of
whether in a flow-style mapping or sequence to get this solved


*When this change indeed resolves your problem, please **Close** this issue*.
*(You can do so usingthe WorkFlow pull-down (close to the top right of this page)*

3 files changed, 57 insertions, 12 deletions

diff --git a/_test/test_issues.py b/_test/test_issues.py
index 7e95857..4ddec2a 100644
--- a/_test/test_issues.py
+++ b/_test/test_issues.py
@@ -44,7 +44,7 @@ class TestIssues:
           key-A:{}
         mapping-B:
         """)
-        for comment in ['', ' # no-newline', '  # some comment\n', '\n', ]:
+        for comment in ['', ' # no-newline', '  # some comment\n', '\n']:
             s = yaml_str.format(comment)
             res = round_trip(s)  # NOQA
 
@@ -65,3 +65,15 @@ class TestIssues:
         - {}
         """)
         x = round_trip(s, preserve_quotes=True)  # NOQA
+
+    json_str = (
+        '{"sshKeys":[{"name":"AETROS\/google-k80-1","uses":0,"getLastUse":0,'
+        '"fingerprint":"MD5:19:dd:41:93:a1:a3:f5:91:4a:8e:9b:d0:ae:ce:66:4c",'
+        '"created":1509497961}]}'
+    )
+
+    json_str2 = '{"abc":[{"a":"1", "uses":0}]}'
+
+    def test_issue_172(self):
+        x = round_trip_load(TestIssues.json_str2)
+        x = round_trip_load(TestIssues.json_str)
diff --git a/main.py b/main.py
index fa9db38..4afaa78 100644
--- a/main.py
+++ b/main.py
@@ -639,7 +639,6 @@ class YAML(object):
             self.constructor.add_constructor(tag, f_y)
         return cls
 
-
     def parse(self, stream):
         # type: (StreamTextType, Any) -> Any
         """
@@ -920,6 +919,14 @@ def load(stream, Loader=None, version=None, preserve_quotes=None):
         return loader._constructor.get_single_data()
     finally:
         loader._parser.dispose()
+        try:
+            loader._reader.reset_reader()  # type: ignore
+        except AttributeError:
+            pass
+        try:
+            loader._scanner.reset_scanner()  # type: ignore
+        except AttributeError:
+            pass
 
 
 def load_all(stream, Loader=None, version=None, preserve_quotes=None):
@@ -937,6 +944,14 @@ def load_all(stream, Loader=None, version=None, preserve_quotes=None):
             yield loader._constructor.get_data()
     finally:
         loader._parser.dispose()
+        try:
+            loader._reader.reset_reader()  # type: ignore
+        except AttributeError:
+            pass
+        try:
+            loader._scanner.reset_scanner()  # type: ignore
+        except AttributeError:
+            pass
 
 
 def safe_load(stream, version=None):
diff --git a/scanner.py b/scanner.py
index 5813c53..c0d376b 100644
--- a/scanner.py
+++ b/scanner.py
@@ -82,14 +82,25 @@ class Scanner(object):
         self.reset_scanner()
         self.first_time = False
 
+    @property
+    def flow_level(self):
+        return len(self.flow_context)
+
+    # @flow_level.setter
+    # def flow_level(self):
+    #     self.flow_context = []
+
     def reset_scanner(self):
         # type: () -> None
         # Had we reached the end of the stream?
         self.done = False
 
+        # flow_context is an expanding/shrinking list consisting of '{' and '['
+        # in general len(flow_context) == flow_level
+        self.flow_context = []
         # The number of unclosed '{' and '['. `flow_level == 0` means block
         # context.
-        self.flow_level = 0
+        self.flow_level_org = 0
 
         # List of processed tokens that are not yet emitted.
         self.tokens = []  # type: List[Any]
@@ -489,18 +500,20 @@ class Scanner(object):
 
     def fetch_flow_sequence_start(self):
         # type: () -> None
-        self.fetch_flow_collection_start(FlowSequenceStartToken)
+        self.fetch_flow_collection_start(FlowSequenceStartToken, to_push='[')
 
     def fetch_flow_mapping_start(self):
         # type: () -> None
-        self.fetch_flow_collection_start(FlowMappingStartToken)
+        self.fetch_flow_collection_start(FlowMappingStartToken, to_push='{')
 
-    def fetch_flow_collection_start(self, TokenClass):
+    def fetch_flow_collection_start(self, TokenClass, to_push):
         # type: (Any) -> None
         # '[' and '{' may start a simple key.
         self.save_possible_simple_key()
         # Increase the flow level.
-        self.flow_level += 1
+        self.flow_level_org += 1
+        self.flow_context.append(to_push)
+        # assert self.flow_level == len(self.flow_context)
         # Simple keys are allowed after '[' and '{'.
         self.allow_simple_key = True
         # Add FLOW-SEQUENCE-START or FLOW-MAPPING-START.
@@ -511,18 +524,20 @@ class Scanner(object):
 
     def fetch_flow_sequence_end(self):
         # type: () -> None
-        self.fetch_flow_collection_end(FlowSequenceEndToken)
+        self.fetch_flow_collection_end(FlowSequenceEndToken, to_pop='[')
 
     def fetch_flow_mapping_end(self):
         # type: () -> None
-        self.fetch_flow_collection_end(FlowMappingEndToken)
+        self.fetch_flow_collection_end(FlowMappingEndToken, to_pop='{')
 
-    def fetch_flow_collection_end(self, TokenClass):
+    def fetch_flow_collection_end(self, TokenClass, to_pop):
         # type: (Any) -> None
         # Reset possible simple key on the current level.
         self.remove_possible_simple_key()
         # Decrease the flow level.
-        self.flow_level -= 1
+        self.flow_level_org -= 1
+        assert self.flow_context.pop() == to_pop
+        assert self.flow_level_org == len(self.flow_context)
         # No simple keys after ']' or '}'.
         self.allow_simple_key = False
         # Add FLOW-SEQUENCE-END or FLOW-MAPPING-END.
@@ -778,7 +793,10 @@ class Scanner(object):
             if bool(self.flow_level):
                 return True
         else:
-            if bool(self.flow_level) and self.reader.peek(1) in '\'"{[]}':
+            if bool(self.flow_level):
+                if self.flow_context[-1] == '[':
+                    return False
+                # if self.reader.peek(1) in '\'"{[]}':
                 return True
         # VALUE(block context): ':' (' '|'\n')
         return self.reader.peek(1) in _THE_END_SPACE_TAB