[Doc] Make Sphinx search work when hosting docs locally

The javascript for the search box wouldn't work due to an earlier
error in the javascript for the version switcher when the switcher
JSON file couldn't be loaded.

doc/SConscript

@@ -54,10 +54,14 @@ if localenv['sphinx_docs']:
                                     "#CONTRIBUTING.md",
                                     Copy("$TARGET", "$SOURCE"))
 
+    copy_switcher = localenv.Command("#build/doc/html/dev/_static/doc-versions.json",
+                                     "sphinx/_static/doc-versions.json",
+                                     Copy("$TARGET", "$SOURCE"))
+
     sphinxdocs = build(localenv.Command('#build/doc/html/index.html',
         'sphinx/conf.py', build_sphinx))
     env.Alias('sphinx', sphinxdocs)
-    env.Depends(sphinxdocs, [copy_sphinx, copy_contrib])
+    env.Depends(sphinxdocs, [copy_sphinx, copy_contrib, copy_switcher])
     env.Depends(sphinxdocs, [copy_python_samples, copy_matlab_ex_samples])
     env.Depends(sphinxdocs, env['python_module'])
 

doc/sphinx/conf.py

@@ -325,7 +325,6 @@ html_theme_options = {
     "primary_sidebar_end": ["numfocus"],
     "switcher": {
         "json_url": "/dev/_static/doc-versions.json",
-        # "json_url": "https://cantera.org/doc-versions.json",
         "version_match": version,
     },
     "check_switcher": False,