Order matters!

src/block-service.js

@@ -26,15 +26,15 @@ function BlockService (ipfsRepo, exchange) {
   }
 
   this.getBlock = (multihash, extension, callback) => {
-    if (!multihash) {
-      return callback(new Error('Invalid multihash'))
-    }
-
     if (typeof extension === 'function') {
       callback = extension
       extension = undefined
     }
 
+    if (!multihash) {
+      return callback(new Error('Invalid multihash'))
+    }
+
     ipfsRepo.datastore.createReadStream(multihash, extension)
       .pipe(bl((err, data) => {
         if (err) { return callback(err) }
@@ -43,15 +43,15 @@ function BlockService (ipfsRepo, exchange) {
   }
 
   this.getBlocks = (multihashes, extension, callback) => {
-    if (!Array.isArray(multihashes)) {
-      return callback(new Error('Invalid batch of multihashes'))
-    }
-
     if (typeof extension === 'function') {
       callback = extension
       extension = undefined
     }
 
+    if (!Array.isArray(multihashes)) {
+      return callback(new Error('Invalid batch of multihashes'))
+    }
+
     const blocks = []
 
     async.each(multihashes, (multihash, next) => {
@@ -65,28 +65,28 @@ function BlockService (ipfsRepo, exchange) {
   }
 
   this.deleteBlock = (multihash, extension, callback) => {
-    if (!multihash) {
-      return callback(new Error('Invalid multihash'))
-    }
-
     if (typeof extension === 'function') {
       callback = extension
       extension = undefined
     }
 
+    if (!multihash) {
+      return callback(new Error('Invalid multihash'))
+    }
+
     ipfsRepo.datastore.remove(multihash, extension, callback)
   }
 
   this.deleteBlocks = (multihashes, extension, callback) => {
-    if (!Array.isArray(multihashes)) {
-      return callback('Invalid batch of multihashes')
-    }
-
     if (typeof extension === 'function') {
       callback = extension
       extension = undefined
     }
 
+    if (!Array.isArray(multihashes)) {
+      return callback('Invalid batch of multihashes')
+    }
+
     async.each(multihashes, (multihash, next) => {
       this.deleteBlock(multihash, extension, next)
     }, (err) => {