Decode percent-encoded characters in internal link paths

src/check.ts

@@ -223,12 +223,16 @@ async function checkInternal(link: LinkInfo, config: Config): Promise<CheckResul
     return { link, ok: true };
   }
 
-  const isRootRelative = urlWithoutAnchor.startsWith('/');
+  // Decode percent-encoded characters (e.g. %20 for spaces) so the path
+  // matches the actual filename on disk.
+  const decodedPath = decodeURIComponent(urlWithoutAnchor);
+
+  const isRootRelative = decodedPath.startsWith('/');
   const sourceDir = path.dirname(path.join(config.repoRoot, link.filePath));
 
   const resolvedPath = isRootRelative
-    ? path.join(config.repoRoot, urlWithoutAnchor)
-    : path.resolve(sourceDir, urlWithoutAnchor);
+    ? path.join(config.repoRoot, decodedPath)
+    : path.resolve(sourceDir, decodedPath);
 
   const exists = fs.existsSync(resolvedPath);
 
@@ -251,9 +255,9 @@ async function checkInternal(link: LinkInfo, config: Config): Promise<CheckResul
 
   // --- Link is broken: search for the target file ---
 
-  const filename = path.basename(urlWithoutAnchor);
-  const stem = path.basename(urlWithoutAnchor, path.extname(urlWithoutAnchor));
-  const ext = path.extname(urlWithoutAnchor);
+  const filename = path.basename(decodedPath);
+  const stem = path.basename(decodedPath, path.extname(decodedPath));
+  const ext = path.extname(decodedPath);
 
   let correctedAbs: string | undefined;
   let isFuzzy = false;

tests/expected-output.txt

@@ -34,10 +34,11 @@ tests/test-document.md:35 | ./configuration.md | broken -> /docs/configuration.m
 tests/test-document.md:37 | ./placeholder.md | ok
 tests/test-document.md:41 | ../AGENTS.md | suggestion
 tests/test-document.md:43 | ../action.yml | suggestion
-tests/test-document.md:53 | https://github.com/dvdstelt/hyperhawk/blob/main/README.md | suggestion -> /README.md
-tests/test-document.md:55 | https://github.com/dvdstelt/hyperhawk/blob/main/tests/test-document.md | suggestion -> test-document.md
-tests/test-document.md:57 | https://github.com/dvdstelt/hyperhawk/blob/main/does-not-exist.md | broken -> /does-not-exist.md
-tests/test-document.md:59 | https://github.com/dvdstelt/hyperhawk/blob/main/docs/configuraton.md | broken -> /docs/configuration.md (fuzzy)
+tests/test-document.md:47 | ./file%20with%20spaces.md | ok
+tests/test-document.md:57 | https://github.com/dvdstelt/hyperhawk/blob/main/README.md | suggestion -> /README.md
+tests/test-document.md:59 | https://github.com/dvdstelt/hyperhawk/blob/main/tests/test-document.md | suggestion -> test-document.md
+tests/test-document.md:61 | https://github.com/dvdstelt/hyperhawk/blob/main/does-not-exist.md | broken -> /does-not-exist.md
+tests/test-document.md:63 | https://github.com/dvdstelt/hyperhawk/blob/main/docs/configuraton.md | broken -> /docs/configuration.md (fuzzy)
 tests/test-document.md:7 | ../READM.md | broken -> /README.md (fuzzy)
 tests/test-document.md:9 | ../LICENS.md | broken | File not found: <root>/LICENS.md
 merge:tests/test-document.md:31 | ../READM.md + ../LICENS.md | Read the [README](/README.md) and the [license](../LICENS.md) before starting.

tests/file with spaces.md

@@ -0,0 +1,3 @@
+# File With Spaces
+
+This file has spaces in its name to test percent-encoded link resolution.

tests/test-document.md

@@ -42,6 +42,10 @@ Look at the [agents guide](../AGENTS.md) for coding conventions.
 
 The [action config](../action.yml) has all the inputs documented.
 
+## Percent-encoded Paths (spaces in filenames)
+
+See the [file with spaces](./file%20with%20spaces.md) for an example.
+
 ## Skipped Links (should not be checked)
 
 Contact us at [email](mailto:user@domain.net) for support.