deduplicate subjects before adding to statement (#180)

Signed-off-by: Brian DeHamer <bdehamer@github.com>

__tests__/subject.test.ts

@@ -362,6 +362,31 @@ describe('subjectFromInputs', () => {
         })
       })
     })
+
+    describe('when duplicate subjects are supplied', () => {
+      let otherDir = ''
+
+      // Add duplicate subject in alternate directory
+      beforeEach(async () => {
+        // Set-up temp directory
+        const tmpDir = await fs.realpath(os.tmpdir())
+        otherDir = await fs.mkdtemp(tmpDir + path.sep)
+
+        // Write file to temp directory
+        await fs.writeFile(path.join(otherDir, filename), content)
+      })
+
+      it('returns de-duplicated subjects', async () => {
+        const inputs: SubjectInputs = {
+          ...blankInputs,
+          subjectPath: `${path.join(dir, 'subject')}, ${path.join(otherDir, 'subject')} `
+        }
+        const subjects = await subjectFromInputs(inputs)
+
+        expect(subjects).toBeDefined()
+        expect(subjects).toHaveLength(1)
+      })
+    })
   })
 })
 

package.json

@@ -1,7 +1,7 @@
 {
   "name": "actions/attest",
   "description": "Generate signed attestations for workflow artifacts",
-  "version": "2.0.0",
+  "version": "2.0.1",
   "author": "",
   "private": true,
   "homepage": "https://github.com/actions/attest",

src/subject.ts

@@ -84,7 +84,14 @@ const getSubjectFromPath = async (
     const name = subjectName || path.parse(file).base
     const digest = await digestFile(DIGEST_ALGORITHM, file)
 
-    digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
+    // Only add the subject if it is not already in the list
+    if (
+      !digestedSubjects.some(
+        s => s.name === name && s.digest[DIGEST_ALGORITHM] === digest
+      )
+    ) {
+      digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
+    }
   }
 
   if (digestedSubjects.length === 0) {