Fixed format string serialization logic, particularly when serializing to JSON.

Author: hcpchris

highcharts_core/js_literal_functions.py

@@ -373,6 +373,12 @@ def get_js_literal(item, careful_validation = False) -> str:
     elif isinstance(item, str):
         if (item.startswith('[') or item.startswith('Date')) and item != 'Date':
             as_str += f"""{item}"""
+        elif item.startswith('${'):
+            if "'" in item:
+                item = item.replace("'", "\\'")
+                as_str += f'"{item[1:]}"'
+            else:
+                as_str += f"'{item[1:]}'"
         elif item.startswith('{') and item.endswith('}'):
             if is_js_object(item, careful_validation = careful_validation):
                 as_str += f"""{item}"""

highcharts_core/metaclasses.py

@@ -220,6 +220,9 @@ def trim_iterable(untrimmed,
         if isinstance(untrimmed, 
                       (str, bytes, dict, UserDict)) or not hasattr(untrimmed, 
                                                                    '__iter__'):
+            if to_json and isinstance(untrimmed, str) and untrimmed.startswith('${'):
+                return untrimmed[1:]
+            
             return untrimmed
 
         trimmed = []

highcharts_core/options/annotations/label_options.py

@@ -295,6 +295,12 @@ def format(self) -> Optional[str]:
 
           * :meth:`PlotOptions.series.data_labels`
 
+        .. warning::
+
+          If your format string begins with ``{`` and ends with ``}``, Highcharts
+          for Python may interpret it as a JavaScript or JSON object. To prevent this, please
+          add a ``$`` before the opening curly brace, like so: ``${value:.1f}``.
+
         :returns: The format string to apply to the labels.
         :rtype: :class:`str <python:str>` or :obj:`None <python:None>`
         """

highcharts_core/options/axes/labels.py

@@ -231,6 +231,12 @@ def format(self) -> Optional[str]:
 
         To add custom numeric or datetime formatting, use ``'{value}'`` with formatting,
         for example ``'{value:.1f}'`` or ``'{value:%Y-%m-%d}'``.
+        
+        .. warning::
+        
+          If your format string begins with ``{`` and ends with ``}``, Highcharts
+          for Python may interpret it as a JavaScript or JSON object. To prevent this, please
+          add a ``$`` before the opening curly brace, like so: ``${value:.1f}``.
 
         :rtype: :class:`str <python:str>` or :obj:`None <python:None>`
         """

highcharts_core/options/series/labels.py

@@ -207,6 +207,12 @@ def format(self) -> Optional[str]:
         ``options.xxx``, ``color``, and other members from the ``series`` object.
         Use this option also to set a static text for the label.
 
+        .. warning::
+
+          If your format string begins with ``{`` and ends with ``}``, Highcharts
+          for Python may interpret it as a JavaScript or JSON object. To prevent this, please
+          add a ``$`` before the opening curly brace, like so: ``${value:.1f}``.
+
         :rtype: :class:`str <python:str>` or :obj:`None <python:None>`
         """
         return self._format

highcharts_core/utility_classes/data_labels.py

@@ -432,6 +432,12 @@ def format(self) -> Optional[str]:
         ``'point.value'``.
 
 
+        .. warning::
+
+          If your format string begins with ``{`` and ends with ``}``, Highcharts
+          for Python may interpret it as a JavaScript or JSON object. To prevent this, please
+          add a ``$`` before the opening curly brace, like so: ``${value}``.
+
         :returns: The format string to apply to the labels.
         :rtype: :class:`str <python:str>` or :obj:`None <python:None>`
         """