fix issue 102 now also for empty mappings with comments0.15.54

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9 files changed, 43 insertions, 35 deletions

diff --git a/CHANGES b/CHANGES
index 951ec0a..c7f4cb9 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,13 @@
+[0, 15, 54]: 2018-08-13
+
+  - fix issue where a comment could pop-up twice in the output (reported by 
+    `Mike Kazantsev <https://bitbucket.org/mk_fg/>`__ and by 
+    `Nate Peterson <https://bitbucket.org/ndpete21/>`__)
+  - fix issue where JSON object (mapping) without spaces was not parsed
+    properly (reported by `Marc Schmidt <https://bitbucket.org/marcj/>`__)
+  - fix issue where comments after empty flow-style mappings were not emitted
+    (reported by `Qinfench Chen <https://bitbucket.org/flyin5ish/>`__)
+
 [0, 15, 53]: 2018-08-12
   - fix issue with flow style mapping with comments gobbled newline (reported
     by `Christopher Lambert <https://bitbucket.org/XN137/>`__)
diff --git a/README.rst b/README.rst
index b7b967b..9182e43 100644
--- a/README.rst
+++ b/README.rst
@@ -4,8 +4,8 @@ ruamel.yaml
 
 ``ruamel.yaml`` is a YAML 1.2 loader/dumper package for Python.
 
-:version:       0.15.53
-:updated:       2018-08-12
+:version:       0.15.54
+:updated:       2018-08-13
 :documentation: http://yaml.readthedocs.io
 :repository:    https://bitbucket.org/ruamel/
 :pypi:          https://pypi.org/project/ruamel.yaml/
@@ -54,6 +54,16 @@ ChangeLog
 
 .. should insert NEXT: at the beginning of line for next key (with empty line)
 
+0.15.54 (2018-08-13):
+
+  - fix issue where a comment could pop-up twice in the output (reported by 
+    `Mike Kazantsev <https://bitbucket.org/mk_fg/>`__ and by 
+    `Nate Peterson <https://bitbucket.org/ndpete21/>`__)
+  - fix issue where JSON object (mapping) without spaces was not parsed
+    properly (reported by `Marc Schmidt <https://bitbucket.org/marcj/>`__)
+  - fix issue where comments after empty flow-style mappings were not emitted
+    (reported by `Qinfench Chen <https://bitbucket.org/flyin5ish/>`__)
+
 0.15.53 (2018-08-12):
   - fix issue with flow style mapping with comments gobbled newline (reported
     by `Christopher Lambert <https://bitbucket.org/XN137/>`__)
diff --git a/__init__.py b/__init__.py
index 1af5ab8..cfddf1b 100644
--- a/__init__.py
+++ b/__init__.py
@@ -7,8 +7,8 @@ if False:  # MYPY
 
 _package_data = dict(
     full_package_name='ruamel.yaml',
-    version_info=(0, 15, 53),
-    __version__='0.15.53',
+    version_info=(0, 15, 54),
+    __version__='0.15.54',
     author='Anthon van der Neut',
     author_email='a.van.der.neut@ruamel.eu',
     description='ruamel.yaml is a YAML parser/emitter that supports roundtrip preservation of comments, seq/map flow style, and map key order',  # NOQA
diff --git a/_doc/_static/pypi.svg b/_doc/_static/pypi.svg
index b218d84..369335f 100644
--- a/_doc/_static/pypi.svg
+++ b/_doc/_static/pypi.svg
@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="86" height="20"><linearGradient id="b" x2="0" y2="100%"><stop offset="0" stop-color="#bbb" stop-opacity=".1"/><stop offset="1" stop-opacity=".1"/></linearGradient><clipPath id="a"><rect width="86" height="20" rx="3" fill="#fff"/></clipPath><g clip-path="url(#a)"><path fill="#555" d="M0 0h33v20H0z"/><path fill="#007ec6" d="M33 0h53v20H33z"/><path fill="url(#b)" d="M0 0h86v20H0z"/></g><g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="110"> <text x="175" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="230">pypi</text><text x="175" y="140" transform="scale(.1)" textLength="230">pypi</text><text x="585" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="430">0.15.53</text><text x="585" y="140" transform="scale(.1)" textLength="430">0.15.53</text></g> </svg>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="86" height="20"><linearGradient id="b" x2="0" y2="100%"><stop offset="0" stop-color="#bbb" stop-opacity=".1"/><stop offset="1" stop-opacity=".1"/></linearGradient><clipPath id="a"><rect width="86" height="20" rx="3" fill="#fff"/></clipPath><g clip-path="url(#a)"><path fill="#555" d="M0 0h33v20H0z"/><path fill="#007ec6" d="M33 0h53v20H33z"/><path fill="url(#b)" d="M0 0h86v20H0z"/></g><g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="110"> <text x="175" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="230">pypi</text><text x="175" y="140" transform="scale(.1)" textLength="230">pypi</text><text x="585" y="150" fill="#010101" fill-opacity=".3" transform="scale(.1)" textLength="430">0.15.54</text><text x="585" y="140" transform="scale(.1)" textLength="430">0.15.54</text></g> </svg>
diff --git a/_test/test_comments.py b/_test/test_comments.py
index bb08f7e..a5e4ee0 100644
--- a/_test/test_comments.py
+++ b/_test/test_comments.py
@@ -59,7 +59,7 @@ class TestComments:
         # comment
         scalar
         ...
-        """, "scalar\n...\n")
+        """, 'scalar\n...\n')
 
     def test_main_mapping_begin_end(self):
         round_trip("""
diff --git a/_test/test_issues.py b/_test/test_issues.py
index fb11322..d2ea460 100644
--- a/_test/test_issues.py
+++ b/_test/test_issues.py
@@ -34,7 +34,7 @@ class TestIssues:
         var4: {a: 1} #filled object
         var5: [] #empty array
         """)
-        x = round_trip(s, preserve_quotes=True)  # NOQA
+        x = round_trip(yaml_str, preserve_quotes=True)  # NOQA
 
     def test_issue_160(self):
         s = dedent("""\
@@ -85,7 +85,5 @@ class TestIssues:
     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)
-
-
+        x = round_trip_load(TestIssues.json_str2)  # NOQA
+        x = round_trip_load(TestIssues.json_str)   # NOQA
diff --git a/emitter.py b/emitter.py
index 4dc053e..7fb572a 100644
--- a/emitter.py
+++ b/emitter.py
@@ -507,9 +507,9 @@ class Emitter(object):
             self.indent = self.indents.pop()
             self.flow_level -= 1
             self.write_indicator(u'}', False)
-            # if self.event.comment and self.event.comment[0]:
-            #     # eol comment on flow sequence
-            #     self.write_post_comment(self.event)
+            if self.event.comment and self.event.comment[0]:
+                # eol comment on empty mapping
+                self.write_post_comment(self.event)
             self.state = self.states.pop()
         else:
             if self.canonical or self.column > self.best_width:
@@ -534,7 +534,7 @@ class Emitter(object):
                 self.write_indent()
             self.write_indicator(u'}', False)
             if self.event.comment and self.event.comment[0]:
-                # eol comment on flow mapping
+                # eol comment on flow mapping, never reached on empty mappings
                 self.write_post_comment(self.event)
             self.state = self.states.pop()
         else:
diff --git a/main.py b/main.py
index 4afaa78..f71a87d 100644
--- a/main.py
+++ b/main.py
@@ -640,7 +640,7 @@ class YAML(object):
         return cls
 
     def parse(self, stream):
-        # type: (StreamTextType, Any) -> Any
+        # type: (StreamTextType) -> Any
         """
         Parse a YAML stream and produce parsing events.
         """
@@ -920,11 +920,11 @@ def load(stream, Loader=None, version=None, preserve_quotes=None):
     finally:
         loader._parser.dispose()
         try:
-            loader._reader.reset_reader()  # type: ignore
+            loader._reader.reset_reader()
         except AttributeError:
             pass
         try:
-            loader._scanner.reset_scanner()  # type: ignore
+            loader._scanner.reset_scanner()
         except AttributeError:
             pass
 
@@ -945,11 +945,11 @@ def load_all(stream, Loader=None, version=None, preserve_quotes=None):
     finally:
         loader._parser.dispose()
         try:
-            loader._reader.reset_reader()  # type: ignore
+            loader._reader.reset_reader()
         except AttributeError:
             pass
         try:
-            loader._scanner.reset_scanner()  # type: ignore
+            loader._scanner.reset_scanner()
         except AttributeError:
             pass
 
diff --git a/scanner.py b/scanner.py
index c0d376b..1e26012 100644
--- a/scanner.py
+++ b/scanner.py
@@ -84,23 +84,17 @@ class Scanner(object):
 
     @property
     def flow_level(self):
+        # type: () -> int
         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_org = 0
+        # for each unclosed flow context. If empty list that means block context
+        self.flow_context = []  # type: List[Text]
 
         # List of processed tokens that are not yet emitted.
         self.tokens = []  # type: List[Any]
@@ -507,13 +501,11 @@ class Scanner(object):
         self.fetch_flow_collection_start(FlowMappingStartToken, to_push='{')
 
     def fetch_flow_collection_start(self, TokenClass, to_push):
-        # type: (Any) -> None
+        # type: (Any, Text) -> None
         # '[' and '{' may start a simple key.
         self.save_possible_simple_key()
         # Increase the flow level.
-        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.
@@ -531,13 +523,11 @@ class Scanner(object):
         self.fetch_flow_collection_end(FlowMappingEndToken, to_pop='{')
 
     def fetch_flow_collection_end(self, TokenClass, to_pop):
-        # type: (Any) -> None
+        # type: (Any, Text) -> None
         # Reset possible simple key on the current level.
         self.remove_possible_simple_key()
         # Decrease the flow level.
-        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.