Crash when .. tab-set:: contains a non .. tab-item:: #243

Closed
#258
Closed
Crash when .. tab-set:: contains a non .. tab-item::#243
#258
Labels
bugSomething isn't working

Description

@ghost
ghost
opened on Sep 14, 2025

Describe the bug

bug

Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.

The following example document illustrates this:
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).

Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

Results in:

 Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

The version used was sphinx-design 0.6.1.

expectation

I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.

sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.

P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.

Reproduce the bug

See example above

List your environment

No response

Metadata

Metadata

Assignees

No one assigned

    Labels

    bugSomething isn't working

    Type

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      , 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
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function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
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observer.observe(document.body, { childList: true, subtree: true });
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})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

      Skip to content
      Crash when .. tab-set:: contains a non .. tab-item:: #243
      Closed
      #258
      Closed
      Crash when .. tab-set:: contains a non .. tab-item::#243
      #258
      Labels
      bugSomething isn't working
      Description
      @ghost
      ghost
      opened on Sep 14, 2025
      Describe the bug
      bug
      Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
      The following example document illustrates this:
      
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
      Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

      Results in:
       Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

      The version used was sphinx-design 0.6.1.
      expectation
      I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
      sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
      P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
      Reproduce the bug
      See example above
      List your environment
      No response
      Metadata
      Metadata
      Assignees
      No one assigned
        Labels
        bugSomething isn't working
        Type
        No type
        Projects
        No projects
          Milestone
          No milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

          Skip to content
          Crash when .. tab-set:: contains a non .. tab-item:: #243
          Closed
          #258
          Closed
          Crash when .. tab-set:: contains a non .. tab-item::#243
          #258
          Labels
          bugSomething isn't working
          Description
          @ghost
          ghost
          opened on Sep 14, 2025
          Describe the bug
          bug
          Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
          The following example document illustrates this:
          
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
          Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

          Results in:
           Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

          The version used was sphinx-design 0.6.1.
          expectation
          I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
          sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
          P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
          Reproduce the bug
          See example above
          List your environment
          No response
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            bugSomething isn't working
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
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found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
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frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              Crash when .. tab-set:: contains a non .. tab-item:: #243
              Closed
              #258
              Closed
              Crash when .. tab-set:: contains a non .. tab-item::#243
              #258
              Labels
              bugSomething isn't working
              Description
              @ghost
              ghost
              opened on Sep 14, 2025
              Describe the bug
              bug
              Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
              The following example document illustrates this:
              
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
              Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

              Results in:
               Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

              The version used was sphinx-design 0.6.1.
              expectation
              I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
              sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
              P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
              Reproduce the bug
              See example above
              List your environment
              No response
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                bugSomething isn't working
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

                  Skip to content
                  Crash when .. tab-set:: contains a non .. tab-item:: #243
                  Closed
                  #258
                  Closed
                  Crash when .. tab-set:: contains a non .. tab-item::#243
                  #258
                  Labels
                  bugSomething isn't working
                  Description
                  @ghost
                  ghost
                  opened on Sep 14, 2025
                  Describe the bug
                  bug
                  Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
                  The following example document illustrates this:
                  
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
                  Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

                  Results in:
                   Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

                  The version used was sphinx-design 0.6.1.
                  expectation
                  I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
                  sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
                  P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
                  Reproduce the bug
                  See example above
                  List your environment
                  No response
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    bugSomething isn't working
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      No milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                      Skip to content
                      Crash when .. tab-set:: contains a non .. tab-item:: #243
                      Closed
                      #258
                      Closed
                      Crash when .. tab-set:: contains a non .. tab-item::#243
                      #258
                      Labels
                      bugSomething isn't working
                      Description
                      @ghost
                      ghost
                      opened on Sep 14, 2025
                      Describe the bug
                      bug
                      Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
                      The following example document illustrates this:
                      
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
                      Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

                      Results in:
                       Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

                      The version used was sphinx-design 0.6.1.
                      expectation
                      I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
                      sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
                      P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
                      Reproduce the bug
                      See example above
                      List your environment
                      No response
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                      Metadata
                      Assignees
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                        Labels
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                          Skip to content
                          Crash when .. tab-set:: contains a non .. tab-item:: #243
                          Closed
                          #258
                          Closed
                          Crash when .. tab-set:: contains a non .. tab-item::#243
                          #258
                          Labels
                          bugSomething isn't working
                          Description
                          @ghost
                          ghost
                          opened on Sep 14, 2025
                          Describe the bug
                          bug
                          Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
                          The following example document illustrates this:
                          
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
                          Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

                          Results in:
                           Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

                          The version used was sphinx-design 0.6.1.
                          expectation
                          I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
                          sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
                          P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
                          Reproduce the bug
                          See example above
                          List your environment
                          No response
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            bugSomething isn't working
                            Type
                            No type
                            Projects
                            No projects
                              Milestone
                              No milestone
                              Relationships
                              None yet
                              Development
                              No branches or pull requests
                              Issue actions
                              
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

                              Skip to content
                              Crash when .. tab-set:: contains a non .. tab-item:: #243
                              Closed
                              #258
                              Closed
                              Crash when .. tab-set:: contains a non .. tab-item::#243
                              #258
                              Labels
                              bugSomething isn't working
                              Description
                              @ghost
                              ghost
                              opened on Sep 14, 2025
                              Describe the bug
                              bug
                              Sphinx -- or more precisely sphinx_design -- crashes when a .. tab-set:: directive contains something other than .. tab-item::.
                              The following example document illustrates this:
                              
(conf.py is generated from sphinx-quickstart and sphinx_design is added to extensions).
                              Tab Test document
=================
.. tab-set::
.. tab-item:: A
A content
foo <------------------ This line is the culprit
.. tab-item:: B
B content

                              Results in:
                               Traceback (most recent call last):
File ".../site-packages/sphinx/cmd/build.py", line 432, in build_main
app.build(args.force_all, args.filenames)
File ".../site-packages/sphinx/application.py", line 426, in build
self.builder.build_update()
File ".../site-packages/sphinx/builders/__init__.py", line 375, in build_update
self.build(
File ".../site-packages/sphinx/builders/__init__.py", line 454, in build
self.write(docnames, updated_docnames, method)
File ".../site-packages/sphinx/builders/__init__.py", line 735, in write
self.write_documents(docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 749, in write_documents
self._write_serial(sorted_docnames)
File ".../site-packages/sphinx/builders/__init__.py", line 765, in _write_serial
doctree = self.env.get_and_resolve_doctree(docname, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/sphinx/environment/__init__.py", line 701, in get_and_resolve_doctree
self.apply_post_transforms(doctree, docname)
File ".../site-packages/sphinx/environment/__init__.py", line 773, in apply_post_transforms
transformer.apply_transforms()
File ".../site-packages/sphinx/transforms/__init__.py", line 92, in apply_transforms
super().apply_transforms() # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../site-packages/docutils/transforms/__init__.py", line 182, in apply_transforms
transform.apply(**kwargs)
File ".../site-packages/sphinx/transforms/post_transforms/__init__.py", line 46, in apply
self.run(**kwargs)
File ".../site-packages/sphinx_design/tabs.py", line 244, in run
tab_label, tab_content = tab_item.children
^^^^^^^^^^^^^^^^^^^^^^
ValueError: not enough values to unpack (expected 2, got 1)

                              The version used was sphinx-design 0.6.1.
                              expectation
                              I expect sphinx-design not to crash but produce a warning/error message similar to an unknown directive/unkown option/malformed list-table, .... and ignoring the .. tab-set:: directive and its contents.
                              sphinx-design could even fail more gracefully by reporting the error but parse .. tab-set:: as best as possible, i.e. collect all .. tab-item:: directive and ignore the rest. In this scenario the build output should then contain the tabs which sphinx-design was able to identify.
                              P.S: Please provide an accurate error location when reporting the reStructuredText error, e.g. line 10 in the example document above.
                              Reproduce the bug
                              See example above
                              List your environment
                              No response
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                bugSomething isn't working
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions