From 79be720eab4c012570ce6cc47e76f9ab8daffec9 Mon Sep 17 00:00:00 2001
From: Ryan Malloy <ryan@supported.systems>
Date: Fri, 13 Feb 2026 03:51:37 -0700
Subject: [PATCH] Add <!-- %revision% --> template placeholder (port of
 upstream PR #492)

Adds a _get_latest_revision() helper that extracts the last entry from
metadata.revisions. Allows templates to show the current revision
indicator without rendering the full revision table.
---
 src/wireviz/templates/README.md | 1 +
 src/wireviz/wv_output.py        | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/src/wireviz/templates/README.md b/src/wireviz/templates/README.md
index 693ea3c..3d08ca6 100644
--- a/src/wireviz/templates/README.md
+++ b/src/wireviz/templates/README.md
@@ -40,6 +40,7 @@ Note that there must be one single space between `--` and `%` at both ends.
 | `<!-- %sheet_total% -->`   | `1` (multi-page documents not yet supported) |
 | `<!-- %diagram% -->`       | Embedded SVG diagram as valid HTML |
 | `<!-- %diagram_png_b64% -->` | Embedded base64 encoded PNG diagram as URI |
+| `<!-- %revision% -->`        | The name of the last revision |
 | `<!-- %{item}% -->`             | String or numeric value of `metadata.{item}` |
 | `<!-- %{item}_{i}% -->`         | Category number `{i}` within dict value of `metadata.{item}` |
 | `<!-- %{item}_{i}_{key}% -->`   | Value of `metadata.{item}.{category}.{key}` |
diff --git a/src/wireviz/wv_output.py b/src/wireviz/wv_output.py
index 084b464..07c9b46 100644
--- a/src/wireviz/wv_output.py
+++ b/src/wireviz/wv_output.py
@@ -64,6 +64,12 @@ def get_mime_subtype(filename: Union[str, Path]) -> str:
     return mime_subtype
 
 
+def _get_latest_revision(metadata: Dict) -> str:
+    if "revisions" not in metadata:
+        return ""
+    return list(metadata.get("revisions"))[-1]
+
+
 def embed_svg_images_file(
     filename_in: Union[str, Path], overwrite: bool = True
 ) -> None:
@@ -152,6 +158,7 @@ def generate_html_output(
         "<!-- %template_sheetsize% -->": metadata.get("template", {}).get(
             "sheetsize", ""
         ),
+        "<!-- %revision% -->": _get_latest_revision(metadata),
     }
 
     def replacement_if_used(key: str, func: Callable[[], str]) -> None: