sagemath_doc_html: Use sphinx_copybutton

Author: Matthias Koeppe

build/pkgs/sagemath_doc_html/dependencies

@@ -1,4 +1,4 @@
-sagelib sphinx pplpy_doc | $(SAGERUNTIME) maxima networkx scipy sympy matplotlib pillow mathjax mpmath ipykernel jupyter_client conway_polynomials tachyon jmol ipywidgets jupyter_sphinx sage_docbuild elliptic_curves furo fpylll
+sagelib sphinx sphinx_copybutton pplpy_doc | $(SAGERUNTIME) maxima networkx scipy sympy matplotlib pillow mathjax mpmath ipykernel jupyter_client conway_polynomials tachyon jmol ipywidgets jupyter_sphinx sage_docbuild elliptic_curves furo fpylll
 
 # Building the documentation has many dependencies, because all
 # documented modules are imported and because we use matplotlib to

src/sage_docbuild/conf.py

@@ -46,6 +46,7 @@
     'sphinx.ext.todo',
     'sphinx.ext.extlinks',
     'sphinx.ext.mathjax',
+    'sphinx_copybutton',
     'IPython.sphinxext.ipython_directive',
     'matplotlib.sphinxext.plot_directive',
     'jupyter_sphinx',
@@ -255,6 +256,11 @@ def set_intersphinx_mappings(app, config):
 # By default document are not master.
 multidocs_is_master = True
 
+# https://sphinx-copybutton.readthedocs.io/en/latest/use.html
+copybutton_prompt_text = r"sage: |[.][.][.][.]: |\$ "
+copybutton_prompt_is_regexp = True
+copybutton_exclude = '.linenos, .gp, .c'  # exclude comments
+
 # Options for HTML output
 # -----------------------