fix: catch eexists in moveOperations promise (#206)

Author: wraithgar

lib/content/write.js

@@ -168,18 +168,21 @@ async function moveToDestination (tmp, cache, sri, opts) {
   moveOperations.set(
     destination,
     fs.mkdir(destDir, { recursive: true })
-      .then(() => moveFile(tmp.target, destination, { overwrite: false }))
+      .then(async () => {
+        await moveFile(tmp.target, destination, { overwrite: false })
+        tmp.moved = true
+        return tmp.moved
+      })
+      .catch(err => {
+        if (!err.message.startsWith('The destination file exists')) {
+          throw Object.assign(err, { code: 'EEXIST' })
+        }
+      }).finally(() => {
+        moveOperations.delete(destination)
+      })
+
   )
-  try {
-    await moveOperations.get(destination)
-    tmp.moved = true
-  } catch (err) {
-    if (!err.message.startsWith('The destination file exists')) {
-      throw Object.assign(err, { code: 'EEXIST' })
-    }
-  } finally {
-    moveOperations.delete(destination)
-  }
+  return moveOperations.get(destination)
 }
 
 function sizeError (expected, found) {

test/put.js

@@ -130,16 +130,21 @@ t.test('signals error if error writing to cache', async t => {
   t.equal(streamErr.code, 'EBADSIZE', 'got error from stream write')
 })
 
-t.test('concurrent puts', async t => {
+t.test('concurrent puts with identical content', async t => {
   const CACHE = t.testdir()
   await Promise.all([
     put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
     put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
     put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
     put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
     put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
     put(CACHE, KEY, CONTENT),
-    put(CACHE, KEY, CONTENT),
+    put(CACHE, `${KEY}2`, CONTENT),
   ])
   const tmpFiles = await fs.readdir(path.join(CACHE, 'tmp'))
   t.strictSame(tmpFiles, [], 'Nothing left in tmp')