set_theme() should accept feature_list (#1078)

* Set multiple themes and flavors

* Add test for gggrid()

* Set theme in global variable.

future_changes.md

@@ -57,4 +57,5 @@
 - Add `linetype` parameter in `elementLine()` and `elementRect()` [[LPK-235](https://github.com/JetBrains/lets-plot-kotlin/issues/235)].
 - Any way to line-wrap facet labels? [[LPK-237](https://github.com/JetBrains/lets-plot-kotlin/issues/237)].
 - Missing marginal gridlines.
-- Cryptic error message on geom_boxplot with orientation="y" [[#600](https://github.com/JetBrains/lets-plot/issues/600)].
+- Cryptic error message on geom_boxplot with orientation="y" [[#600](https://github.com/JetBrains/lets-plot/issues/600)].
+- `set_theme()` should accept "feature list" [[#657](https://github.com/JetBrains/lets-plot/issues/657)].

python-package/lets_plot/__init__.py

@@ -2,21 +2,21 @@
 # Copyright (c) 2019. JetBrains s.r.o.
 # Use of this source code is governed by the MIT license that can be found in the LICENSE file.
 #
-import json
 from pkgutil import extend_path
-from typing import Dict
+from typing import Dict, Union
 
 # To handle the situation when the 'lets_plot' package is shared by modules in different locations.
 __path__ = extend_path(__path__, __name__)
 
 from ._version import __version__
-from ._global_settings import _settings, is_production, get_global_bool, PLOT_THEME
+from ._global_settings import _settings, is_production, get_global_bool
 from ._global_settings import NO_JS, OFFLINE
 
 from .plot import *
 from .export import *
 from .frontend_context import *
 from .settings_utils import *
+from .plot._global_theme import _set_global_theme
 
 __all__ = (plot.__all__ +
  frontend_context.__all__ +
@@ -161,22 +161,20 @@ def set(cls, settings: Dict):
  _settings.update({'dev_' + key: value for key, value in settings.items()})
 
  @classmethod
- def set_theme(cls, theme: 'plot.FeatureSpec'):
+ def set_theme(cls, theme: Union['core.FeatureSpec', 'core.FeatureSpecArray']):
  """
  Set up global theme.
 
  Parameters
  ----------
  theme : spec
- Theme spec provided by `theme(...)` or `theme_xxx()` functions.
+ Theme spec provided by `theme(...)`, `theme_xxx()`, `flavor_xxx()` functions, or their sum.
 
  """
- if theme.kind != 'theme':
- raise ValueError("Wrong option type. Expected `theme` but was `{}`.".format(theme.kind))
+ if theme.kind != 'theme' and not (theme.kind == 'feature-list' and all(f.kind == 'theme' for f in theme)):
+ raise ValueError("Only `theme(...)`, `theme_xxx()`, `flavor_xxx()`, or a sum of them are supported")
 
- LetsPlot.set({
- PLOT_THEME: json.dumps(theme.as_dict())
- })
+ _set_global_theme(theme)
 
  @classmethod
  def setup_show_ext(cls, *,
@@ -276,4 +274,4 @@ def setup_show_ext(cls, *,
  p.show()
 
  """
- cfg._setup_wb_html_context(exec=exec, new=new)
+ cfg._setup_wb_html_context(exec=exec, new=new)

python-package/lets_plot/_global_settings.py

@@ -45,7 +45,6 @@
 JS_URL_MANUAL = 'js_url_manual'
 MAX_WIDTH = 'max_width'
 MAX_HEIGHT = 'max_height'
-PLOT_THEME = 'plot_theme'
 
 MAPTILES_KIND = 'maptiles_kind'
 MAPTILES_URL = 'maptiles_url'

python-package/lets_plot/plot/_global_theme.py

@@ -0,0 +1,14 @@
+#
+# Copyright (c) 2024. JetBrains s.r.o.
+# Use of this source code is governed by the MIT license that can be found in the LICENSE file.
+#
+_global_theme = None
+
+
+def _set_global_theme(theme):
+ global _global_theme
+ _global_theme = theme
+
+
+def _get_global_theme():
+ return _global_theme

python-package/lets_plot/plot/gggrid_.py

@@ -2,12 +2,11 @@
 # Copyright (c) 2023. JetBrains s.r.o.
 # Use of this source code is governed by the MIT license that can be found in the LICENSE file.
 #
-import json
 
-from lets_plot._global_settings import has_global_value, get_global_val, PLOT_THEME
 from lets_plot.plot.core import FeatureSpec, PlotSpec
 from .subplots import SupPlotsLayoutSpec
 from .subplots import SupPlotsSpec
+from ._global_theme import _get_global_theme
 
 __all__ = ['gggrid']
 
@@ -116,7 +115,7 @@ def gggrid(plots: list, ncol: int = None, *,
  )
 
  # Global Theme
- global_theme_options = json.loads(get_global_val(PLOT_THEME)) if has_global_value(PLOT_THEME) else None
+ global_theme_options = _get_global_theme()
 
  def _strip_theme_if_global(fig):
  # Strip global theme options from plots in grid (see issue: #966).
@@ -136,7 +135,6 @@ def _strip_theme_if_global(fig):
  figure_spec = SupPlotsSpec(figures=figures, layout=layout)
 
  if global_theme_options is not None:
- theme_name = global_theme_options.pop('name', None)
- figure_spec += FeatureSpec('theme', theme_name, **global_theme_options)
+ figure_spec += global_theme_options
 
  return figure_spec

python-package/lets_plot/plot/plot.py

@@ -2,14 +2,14 @@
 # Copyright (c) 2019. JetBrains s.r.o.
 # Use of this source code is governed by the MIT license that can be found in the LICENSE file.
 #
-import json
 import numbers
 
-from lets_plot._global_settings import has_global_value, get_global_val, MAX_WIDTH, MAX_HEIGHT, PLOT_THEME
+from lets_plot._global_settings import has_global_value, get_global_val, MAX_WIDTH, MAX_HEIGHT
 from lets_plot.geo_data_internals.utils import is_geocoder
 from lets_plot.plot.core import FeatureSpec
 from lets_plot.plot.core import PlotSpec
 from lets_plot.plot.util import as_annotated_data
+from lets_plot.plot._global_theme import _get_global_theme
 
 __all__ = ['ggplot', 'ggsize', 'GGBunch']
 
@@ -87,10 +87,8 @@ def ggplot(data=None, mapping=None):
 
  plot_spec = PlotSpec(data, mapping, scales=[], layers=[], **data_meta)
 
- if has_global_value(PLOT_THEME):
- theme_options = json.loads(get_global_val(PLOT_THEME))
- theme_name = theme_options.pop('name', None)
- plot_spec += FeatureSpec('theme', theme_name, **theme_options)
+ if _get_global_theme() is not None:
+ plot_spec += _get_global_theme()
 
  return plot_spec
 

python-package/test/plot/test_theme.py

@@ -60,6 +60,7 @@ def test_plot_theme_element_values_merged():
  assert 'b' == rect['fill']
  assert 1 == rect['size']
 
+
 def test_gggrid_theme_element_values_merged():
  spec = (gg.gggrid(plots=[gg.ggplot() + _geom('foo')])
  + theme(panel_background=element_rect(color='a', fill='b'))
@@ -93,6 +94,39 @@ def test_global_theme_overriding():
  assert 'top' == spec.as_dict()['theme']['legend_position']
 
 
+def test_global_theme_feature_add():
+ gg.LetsPlot.set_theme(
+ theme_classic() + flavor_darcula() + theme(legend_position='bottom')
+ )
+
+ spec = gg.ggplot() + _geom('foo')
+ expected_theme = {
+ 'name': 'classic',
+ 'flavor': 'darcula',
+ 'legend_position': 'bottom'
+ }
+
+ assert expected_theme == spec.as_dict()['theme']
+
+
+def test_global_theme_feature_add_for_gggrid():
+ gg.LetsPlot.set_theme(
+ theme_classic() + flavor_darcula() + theme(legend_position='bottom')
+ )
+
+ spec_foo = gg.ggplot() + _geom('foo')
+ spec_bar = gg.ggplot() + _geom('bar')
+ spec = gg.gggrid([spec_foo, spec_bar])
+
+ expected_theme = {
+ 'name': 'classic',
+ 'flavor': 'darcula',
+ 'legend_position': 'bottom'
+ }
+
+ assert expected_theme == spec.as_dict()['theme']
+
+
 def test_overriding_global_named_theme():
  gg.LetsPlot.set_theme(
  theme_classic()