feat(docs): Render argparse metadata as semantic definition list

Replace inline pipe-separated metadata (Default: None | Type: str | Required)
with a semantic <dl> structure that enables independent CSS styling of keys,
values, and tags. Uses Furo's guilabel pattern for Required tag with
semi-transparent amber background for light/dark mode compatibility.

Author: tony

docs/_ext/sphinx_argparse_neo/nodes.py

@@ -518,30 +518,46 @@ def depart_argparse_argument_html(
     node : argparse_argument
         The argument node being departed.
     """
-    # Add metadata (default, choices, type)
-    metadata: list[str] = []
-
+    # Build metadata as definition list items
     default = node.get("default_string")
-    if default is not None:
-        # Wrap default value in nv span for yellow/italic styling
-        metadata.append(f'Default: <span class="nv">{self.encode(default)}</span>')
-
     choices = node.get("choices")
-    if choices:
-        choices_str = ", ".join(str(c) for c in choices)
-        metadata.append(f"Choices: {self.encode(choices_str)}")
-
     type_name = node.get("type_name")
-    if type_name:
-        metadata.append(f"Type: {self.encode(type_name)}")
-
     required = node.get("required", False)
-    if required:
-        metadata.append("Required")
 
-    if metadata:
-        meta_str = " | ".join(metadata)
-        self.body.append(f'<p class="argparse-argument-meta">{meta_str}</p>')
+    if default is not None or choices or type_name or required:
+        self.body.append('<dl class="argparse-argument-meta">\n')
+
+        if default is not None:
+            self.body.append('<div class="argparse-meta-item">')
+            self.body.append('<dt class="argparse-meta-key">Default</dt>')
+            self.body.append(
+                f'<dd class="argparse-meta-value">'
+                f'<span class="nv">{self.encode(default)}</span></dd>'
+            )
+            self.body.append("</div>\n")
+
+        if type_name:
+            self.body.append('<div class="argparse-meta-item">')
+            self.body.append('<dt class="argparse-meta-key">Type</dt>')
+            self.body.append(
+                f'<dd class="argparse-meta-value">'
+                f'<span class="nv">{self.encode(type_name)}</span></dd>'
+            )
+            self.body.append("</div>\n")
+
+        if choices:
+            choices_str = ", ".join(str(c) for c in choices)
+            self.body.append('<div class="argparse-meta-item">')
+            self.body.append('<dt class="argparse-meta-key">Choices</dt>')
+            self.body.append(
+                f'<dd class="argparse-meta-value">{self.encode(choices_str)}</dd>'
+            )
+            self.body.append("</div>\n")
+
+        if required:
+            self.body.append('<dt class="argparse-meta-tag">Required</dt>\n')
+
+        self.body.append("</dl>\n")
 
     self.body.append("</dd>\n")
     # Close wrapper div

docs/_static/css/argparse-highlight.css

@@ -348,18 +348,65 @@ body:not([data-theme="dark"]) .argparse-argument-name .headerlink {
 }
 
 /*
- * Default value styling in metadata
- * Styled like inline code with monokai background.
+ * Argument metadata definition list
+ *
+ * Renders metadata (Default, Type, Choices, Required) as a horizontal
+ * flexbox of key-value pairs and standalone tags.
  */
-.argparse-argument-meta .nv {
+.argparse-argument-meta {
+	margin: 0.5rem 0 0 0;
+	padding: 0;
+	display: flex;
+	flex-wrap: wrap;
+	gap: 0.5rem 1rem;
+	align-items: center;
+}
+
+.argparse-meta-item {
+	display: flex;
+	align-items: center;
+	gap: 0.25rem;
+}
+
+.argparse-meta-key {
+	color: var(--color-foreground-secondary, #6c757d);
+	font-size: var(--font-size--small);
+}
+
+.argparse-meta-key::after {
+	content: ":";
+}
+
+.argparse-meta-value .nv {
 	background: var(--argparse-code-background);
 	border-radius: 0.2rem;
-	padding: 0.1405rem 0.3rem;
+	padding: 0.1rem 0.3rem;
 	font-family: var(--font-stack--monospace);
 	font-size: var(--font-size--small);
 	color: #e5c07b;
 }
 
+/*
+ * Meta tag (e.g., "Required") - follows Furo's guilabel pattern
+ * Uses semi-transparent amber background with border for visibility
+ * without the harshness of solid fills. Amber conveys "needs attention".
+ */
+.argparse-meta-tag {
+	background-color: #fef3c780;
+	border: 1px solid #fcd34d80;
+	color: var(--color-foreground-primary);
+	font-size: var(--font-size--small);
+	padding: 0.1rem 0.4rem;
+	border-radius: 0.2rem;
+	font-weight: 500;
+}
+
+/* Dark mode: darker amber with adjusted border */
+body[data-theme="dark"] .argparse-meta-tag {
+	background-color: #78350f60;
+	border-color: #b4530980;
+}
+
 /*
  * Help text description
  * Adds spacing above for visual separation from argument name.

tests/docs/_ext/sphinx_argparse_neo/test_nodes.py

@@ -314,6 +314,8 @@ class ArgumentHTMLCase(t.NamedTuple):
     metavar: str | None
     help_text: str | None
     default: str | None
+    type_name: str | None
+    required: bool
     id_prefix: str
     expected_patterns: list[str]  # Regex patterns to match
 
@@ -325,14 +327,18 @@ class ArgumentHTMLCase(t.NamedTuple):
         metavar="socket-name",
         help_text="pass-through for tmux -L",
         default="None",
+        type_name=None,
+        required=False,
         id_prefix="shell",
         expected_patterns=[
             r'<div class="argparse-argument-wrapper" id="shell-L">',
             r'<dt class="argparse-argument-name">',
             r'<span class="na">-L</span>',
             r'<span class="nv">socket-name</span>',
             r'<a class="headerlink" href="#shell-L">¶</a>',
-            r'Default: <span class="nv">None</span>',
+            r'<dl class="argparse-argument-meta">',
+            r'<dt class="argparse-meta-key">Default</dt>',
+            r'<dd class="argparse-meta-value"><span class="nv">None</span></dd>',
             r"</div>",
         ],
     ),
@@ -342,6 +348,8 @@ class ArgumentHTMLCase(t.NamedTuple):
         metavar=None,
         help_text="show help",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="",
         expected_patterns=[
             r'<span class="nt">--help</span>',
@@ -355,6 +363,8 @@ class ArgumentHTMLCase(t.NamedTuple):
         metavar=None,
         help_text="input file",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="",
         expected_patterns=[
             r'<span class="nl">filename</span>',
@@ -367,6 +377,8 @@ class ArgumentHTMLCase(t.NamedTuple):
         metavar=None,
         help_text="Enable verbose mode",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="load",
         expected_patterns=[
             r'id="load-v-verbose"',
@@ -375,6 +387,25 @@ class ArgumentHTMLCase(t.NamedTuple):
             r'href="#load-v-verbose"',
         ],
     ),
+    ArgumentHTMLCase(
+        test_id="metadata_definition_list",
+        names=["workspace_file"],
+        metavar="workspace-file",
+        help_text="checks current tmuxp for workspace files.",
+        default="None",
+        type_name="str",
+        required=True,
+        id_prefix="edit",
+        expected_patterns=[
+            r'<dl class="argparse-argument-meta">',
+            r'<dt class="argparse-meta-key">Default</dt>',
+            r'<dd class="argparse-meta-value"><span class="nv">None</span></dd>',
+            r'<dt class="argparse-meta-key">Type</dt>',
+            r'<dd class="argparse-meta-value"><span class="nv">str</span></dd>',
+            r'<dt class="argparse-meta-tag">Required</dt>',
+            r"</dl>",
+        ],
+    ),
 ]
 
 
@@ -395,6 +426,8 @@ def render_argument_to_html(
     metavar: str | None,
     help_text: str | None,
     default: str | None,
+    type_name: str | None,
+    required: bool,
     id_prefix: str,
 ) -> str:
     """Render an argument node to HTML string for testing.
@@ -409,6 +442,10 @@ def render_argument_to_html(
         Help text for the argument.
     default
         Default value string.
+    type_name
+        Type name for the argument (e.g., "str", "int").
+    required
+        Whether the argument is required.
     id_prefix
         Prefix for the argument ID.
 
@@ -427,6 +464,8 @@ def render_argument_to_html(
     node["metavar"] = metavar
     node["help"] = help_text
     node["default_string"] = default
+    node["type_name"] = type_name
+    node["required"] = required
     node["id_prefix"] = id_prefix
 
     translator = MockTranslator()
@@ -448,6 +487,8 @@ def test_argument_html_rendering(case: ArgumentHTMLCase) -> None:
         metavar=case.metavar,
         help_text=case.help_text,
         default=case.default,
+        type_name=case.type_name,
+        required=case.required,
         id_prefix=case.id_prefix,
     )
 
@@ -462,6 +503,8 @@ def test_argument_wrapper_has_id() -> None:
         metavar="PATH",
         help_text="Input file",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="convert",
     )
 
@@ -476,23 +519,29 @@ def test_argument_headerlink_present() -> None:
         metavar="FILE",
         help_text="Output file",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="freeze",
     )
 
     assert '<a class="headerlink" href="#freeze-output">¶</a>' in html
 
 
 def test_default_value_styled() -> None:
-    """Verify default value is wrapped in nv span."""
+    """Verify default value is wrapped in nv span within definition list."""
     html = render_argument_to_html(
         names=["--format"],
         metavar=None,
         help_text="Output format",
         default="json",
+        type_name=None,
+        required=False,
         id_prefix="",
     )
 
-    assert 'Default: <span class="nv">json</span>' in html
+    assert '<dl class="argparse-argument-meta">' in html
+    assert '<dt class="argparse-meta-key">Default</dt>' in html
+    assert '<dd class="argparse-meta-value"><span class="nv">json</span></dd>' in html
 
 
 def test_wrapper_div_closed() -> None:
@@ -502,6 +551,8 @@ def test_wrapper_div_closed() -> None:
         metavar=None,
         help_text="Verbose",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="",
     )
 
@@ -518,8 +569,46 @@ def test_argument_no_id_prefix() -> None:
         metavar=None,
         help_text="Enable debug mode",
         default=None,
+        type_name=None,
+        required=False,
         id_prefix="",
     )
 
     assert 'id="debug"' in html
     assert 'href="#debug"' in html
+
+
+def test_metadata_uses_definition_list() -> None:
+    """Verify metadata renders as definition list, not inline paragraph."""
+    html = render_argument_to_html(
+        names=["--format"],
+        metavar=None,
+        help_text="Output format",
+        default="json",
+        type_name="str",
+        required=False,
+        id_prefix="",
+    )
+
+    assert '<dl class="argparse-argument-meta">' in html
+    assert '<dt class="argparse-meta-key">Default</dt>' in html
+    assert '<dd class="argparse-meta-value"><span class="nv">json</span></dd>' in html
+    assert '<dt class="argparse-meta-key">Type</dt>' in html
+    assert '<dd class="argparse-meta-value"><span class="nv">str</span></dd>' in html
+
+
+def test_required_renders_as_tag() -> None:
+    """Verify Required renders as standalone tag, not key-value."""
+    html = render_argument_to_html(
+        names=["--config"],
+        metavar="FILE",
+        help_text="Config file",
+        default=None,
+        type_name=None,
+        required=True,
+        id_prefix="",
+    )
+
+    assert '<dt class="argparse-meta-tag">Required</dt>' in html
+    # Should NOT have a matching dd for Required
+    assert 'argparse-meta-value">Required' not in html