`:maxdepth: option of toctree affects secnumdepth` (ref: #2547)

CHANGES

@@ -15,6 +15,7 @@ Features added
 * #2471: Add config variable for default doctest flags.
 * Convert linkcheck builder to requests for better encoding handling
 * #2463, #2516: Add keywords of "meta" directive to search index
+* ``:maxdepth:`` option of toctree affects ``secnumdepth`` (ref: #2547)
 
 Bugs fixed
 ----------

sphinx/writers/latex.py

@@ -52,6 +52,7 @@ HEADER = r'''%% Generated by Sphinx.
 %(numfig_format)s
 %(pageautorefname)s
 %(tocdepth)s
+%(secnumdepth)s
 %(preamble)s
 
 \title{%(title)s}
@@ -77,6 +78,7 @@ FOOTER = r'''
 '''
 
 URI_SCHEMES = ('mailto:', 'http:', 'https:', 'ftp:')
+SECNUMDEPTH = 3
 
 
 class collected_footnote(nodes.footnote):
@@ -323,6 +325,7 @@ class LaTeXTranslator(nodes.NodeVisitor):
         'transition':      '\n\n\\bigskip\\hrule{}\\bigskip\n\n',
         'figure_align':    'htbp',
         'tocdepth':        '',
+        'secnumdepth':     '',
         'pageautorefname': '',
     }
 
@@ -438,8 +441,11 @@ class LaTeXTranslator(nodes.NodeVisitor):
             #   tocdepth =  1: show parts, chapters and sections
             #   tocdepth =  2: show parts, chapters, sections and subsections
             #   ...
-            self.elements['tocdepth'] = ('\\setcounter{tocdepth}{%d}' %
-                                         (document['tocdepth'] + self.top_sectionlevel - 2))
+            tocdepth = document['tocdepth'] + self.top_sectionlevel - 2
+            self.elements['tocdepth'] = '\\setcounter{tocdepth}{%d}' % tocdepth
+            if tocdepth >= SECNUMDEPTH:
+                # Increase secnumdepth if tocdepth is depther than default SECNUMDEPTH
+                self.elements['secnumdepth'] = '\\setcounter{secnumdepth}{%d}' % tocdepth
         if getattr(document.settings, 'contentsname', None):
             self.elements['contentsname'] = \
                 self.babel_renewcommand('\\contentsname', document.settings.contentsname)

tests/roots/test-toctree-maxdepth/qux.rst

@@ -0,0 +1,9 @@
+test-toctree-max-depth
+======================
+
+.. toctree::
+   :numbered:
+   :maxdepth: 4
+
+   foo
+   bar

tests/test_build_latex.py

@@ -589,6 +589,7 @@ def test_toctree_maxdepth_manual(app, status, warning):
     print(status.getvalue())
     print(warning.getvalue())
     assert '\\setcounter{tocdepth}{1}' in result
+    assert '\\setcounter{secnumdepth}' not in result
 
 
 @with_app(buildername='latex', testroot='toctree-maxdepth',
@@ -603,6 +604,7 @@ def test_toctree_maxdepth_howto(app, status, warning):
     print(status.getvalue())
     print(warning.getvalue())
     assert '\\setcounter{tocdepth}{2}' in result
+    assert '\\setcounter{secnumdepth}' not in result
 
 
 @with_app(buildername='latex', testroot='toctree-maxdepth',
@@ -614,6 +616,7 @@ def test_toctree_not_found(app, status, warning):
     print(status.getvalue())
     print(warning.getvalue())
     assert '\\setcounter{tocdepth}' not in result
+    assert '\\setcounter{secnumdepth}' not in result
 
 
 @with_app(buildername='latex', testroot='toctree-maxdepth',
@@ -625,6 +628,19 @@ def test_toctree_without_maxdepth(app, status, warning):
     print(status.getvalue())
     print(warning.getvalue())
     assert '\\setcounter{tocdepth}' not in result
+    assert '\\setcounter{secnumdepth}' not in result
+
+
+@with_app(buildername='latex', testroot='toctree-maxdepth',
+          confoverrides={'master_doc': 'qux'})
+def test_toctree_with_deeper_maxdepth(app, status, warning):
+    app.builder.build_all()
+    result = (app.outdir / 'Python.tex').text(encoding='utf8')
+    print(result)
+    print(status.getvalue())
+    print(warning.getvalue())
+    assert '\\setcounter{tocdepth}{3}' in result
+    assert '\\setcounter{secnumdepth}{3}' in result
 
 
 @with_app(buildername='latex', testroot='toctree-maxdepth',