throw error if file not exists

closes #43

Author: haoxin

index.js

@@ -4,6 +4,7 @@
 
 const debug = require('debug')('koa-send');
 const resolvePath = require('resolve-path');
+const createError = require('http-errors');
 const assert = require('assert');
 const fs = require('mz/fs');
 
@@ -59,7 +60,7 @@ async function send(ctx, path, opts = {}) {
   // normalize path
   path = decode(path);
 
-  if (-1 == path) return ctx.throw('failed to decode', 400);
+  if (-1 == path) return ctx.throw(400, 'failed to decode');
 
   // index file support
   if (index && trailingSlash) path += index;
@@ -109,7 +110,9 @@ async function send(ctx, path, opts = {}) {
     }
   } catch (err) {
     const notfound = ['ENOENT', 'ENAMETOOLONG', 'ENOTDIR'];
-    if (~notfound.indexOf(err.code)) return;
+    if (notfound.includes(err.code)) {
+      throw createError(404, err);
+    }
     err.status = 500;
     throw err;
   }

package.json

@@ -22,6 +22,7 @@
   "license": "MIT",
   "dependencies": {
     "debug": "^2.6.3",
+    "http-errors": "^1.6.1",
     "mz": "^2.6.0",
     "resolve-path": "^1.3.3"
   },

test/index.js

@@ -19,6 +19,26 @@ describe('send(ctx, file)', function(){
         .get('/')
         .expect(404, done);
       })
+
+      it('should throw 404 error', function(done){
+        const app = new Koa()
+
+        let error
+        app.use(async (ctx) => {
+          try {
+            await send(ctx, __dirname + '/fixtures/hello.txt')
+          } catch (err) {
+            error = err
+          }
+        })
+
+        request(app.listen())
+        .get('/')
+        .expect(404, () => {
+          assert.equal(error.status, 404)
+          done()
+        })
+      })
     })
 
     describe('when the path is relative', function(){