From 426bde483838a3126de120e3706d0682d70d65be Mon Sep 17 00:00:00 2001
From: Liang Xu <lx3133584@users.noreply.github.com>
Date: Thu, 27 Aug 2026 04:06:51 +0800
Subject: [PATCH] fix(svg): fallback to svg type when metadata parser fails on
 symbol-based SVGs

Fixes #287

Signed-off-by: Liang Xu <lx3133584@users.noreply.github.com>
---
 src/ipx.ts       | 22 ++++++++++++++++------
 test/svg.test.ts |  7 +++++++
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/src/ipx.ts b/src/ipx.ts
index 6d8cc81..1432bc1 100644
--- a/src/ipx.ts
+++ b/src/ipx.ts
@@ -340,12 +340,22 @@ export function createIPX(userOptions: IPXOptions): IPX {
       let imageMeta: ImageMeta;
       try {
         imageMeta = getImageMeta(sourceData) as ImageMeta;
-      } catch {
-        throw new HTTPError({
-          statusCode: 400,
-          statusText: `IPX_INVALID_IMAGE`,
-          message: `Cannot parse image metadata: ${id}`,
-        });
+      } catch (error) {
+        const textSample = sourceData.subarray(0, 1024).toString("utf8");
+        if (textSample.includes("<svg") || id.endsWith(".svg")) {
+          imageMeta = {
+            type: "svg",
+            width: undefined,
+            height: undefined,
+          } as ImageMeta;
+        } else {
+          throw new HTTPError({
+            statusCode: 400,
+            statusText: `IPX_INVALID_IMAGE`,
+            message: `Cannot parse image metadata: ${id}`,
+            cause: error,
+          });
+        }
       }
 
       // Determine format
diff --git a/test/svg.test.ts b/test/svg.test.ts
index 516d8b1..64cc0ff 100644
--- a/test/svg.test.ts
+++ b/test/svg.test.ts
@@ -202,6 +202,13 @@ describe("optimize svg", () => {
       statusText: "IPX_INVALID_SVG",
     });
   });
+
+  it("processes svg with symbol and use tags without dimensions on root", async () => {
+    const svgWithSymbol = `<svg xmlns="http://www.w3.org/2000/svg"><symbol id="icon-glasses" viewBox="0 0 111.58 77.24" fill="none"><circle cx="50" cy="50" r="40"/></symbol><use href="#icon-glasses"/></svg>`;
+    const output = await processSVG(svgWithSymbol);
+    expect(output).toContain("<symbol id=");
+    expect(output).toContain("<use href=");
+  });
 });
 
 it("svg.unsafeSkipSanitize opts out of sanitization", async () => {