fix: fix broken link behavrior with files in subdirectories

rules/file-no-broken-links.js

@@ -34,7 +34,7 @@ async function fileNoBrokenLinks(fs, options) {
   const results = await Promise.all(
     files.map(async f => {
       // render it, if possible
-      const absMdPath = path.resolve(fs.targetDir, f)
+      const absMdPath = path.posix.resolve(fs.targetDir, f)
       const rendered = await GitHubMarkup.renderMarkup(absMdPath)
       if (rendered === null) {
         return {
@@ -60,7 +60,7 @@ async function fileNoBrokenLinks(fs, options) {
       )
       await htmlChecker.scan(
         rendered,
-        new URL(`file://${path.posix.join(fs.targetDir, '/')}`)
+        new URL(`file://${path.posix.join(fs.targetDir, f)}`)
       )
       // find all relative links, and double check the filesystem for their existence
       // filter down to broken links

tests/rules/file_no_broken_links_tests.js

@@ -199,6 +199,36 @@ describe('rule', () => {
         })
       })
 
+      it('returns true with link to a file outside a subdirectory markdown', async () => {
+        const ruleopts = {
+          globsAll: ['subdirectory/nested_relative_link.md']
+        }
+
+        const actual = await fileNoBrokenLinks(testFs, ruleopts)
+
+        expect(actual.passed).to.equal(true)
+        expect(actual.targets).to.have.length(1)
+        expect(actual.targets[0]).to.deep.include({
+          passed: true,
+          path: 'subdirectory/nested_relative_link.md'
+        })
+      })
+
+      it('returns false with an invalid link to a file outside a subdirectory markdown', async () => {
+        const ruleopts = {
+          globsAll: ['subdirectory/invalid_nested_relative_link.md']
+        }
+
+        const actual = await fileNoBrokenLinks(testFs, ruleopts)
+
+        expect(actual.passed).to.equal(false)
+        expect(actual.targets).to.have.length(1)
+        expect(actual.targets[0]).to.deep.include({
+          passed: false,
+          path: 'subdirectory/invalid_nested_relative_link.md'
+        })
+      })
+
       it('returns false with a relative link to a file in markdown outside the working directory', async () => {
         const ruleopts = {
           globsAll: ['relative_link_outside_dir.md']

tests/rules/markup_test_files/subdirectory/invalid_nested_relative_link.md

@@ -0,0 +1 @@
+[my file](../notafile)

tests/rules/markup_test_files/subdirectory/nested_relative_link.md

@@ -0,0 +1 @@
+[my file](../link.md)