fix: ignore external https image links

src/index.js

@@ -70,11 +70,24 @@ const relativeLinksRule = {
           url = new URL(hrefSrc, pathToFileURL(params.name))
         }
 
-        if (url.protocol !== "file:" && type !== "image") {
+        const detail = `"${hrefSrc}"`
+
+        if (
+          type === "image" &&
+          url.protocol !== "file:" &&
+          url.protocol !== "http:" &&
+          url.protocol !== "https:"
+        ) {
+          onError({
+            lineNumber,
+            detail: `${detail} should be an image`,
+          })
           continue
         }
 
-        const detail = `"${hrefSrc}"`
+        if (url.protocol !== "file:") {
+          continue
+        }
 
         if (!fs.existsSync(url)) {
           onError({

test/fixtures/valid/ignore-external-image.md

@@ -0,0 +1,3 @@
+# Valid
+
+![External Image](https://example.com/image.png)

test/index.test.js

@@ -152,7 +152,7 @@ test("ensure the rule validates correctly", async (t) => {
         fixturePath: "test/fixtures/invalid/invalid-image.md",
         errors: [
           '"../not-an-image.txt" should be an image',
-          '"mailto:not-an-image@pictures.com" should exist in the file system',
+          '"mailto:not-an-image@pictures.com" should be an image',
         ],
       },
     ]
@@ -239,6 +239,10 @@ test("ensure the rule validates correctly", async (t) => {
           },
         },
       },
+      {
+        name: "should ignore external image links",
+        fixturePath: "test/fixtures/valid/ignore-external-image.md",
+      },
     ]
 
     for (const { name, fixturePath, config = defaultConfig } of testCases) {