Fix handling of exceptions when cache enabled

closes #156
fixes #165

HISTORY.md

@@ -2,6 +2,7 @@ unreleased
 ==========
 
   * Fix async helpers not working when cache enabled
+  * Fix handling of exceptions when cache enabled
   * deps: handlebars@4.1.2
   * deps: walk@2.3.14
 

lib/hbs.js

@@ -46,14 +46,19 @@ function middleware(filename, options, cb) {
     // cached?
     var template = cache[filename];
     if (template) {
-      var res = template(locals, handlebarsOpts)
-      self.async.done(function (values) {
-        Object.keys(values).forEach(function (id) {
-          res = res.replace(id, values[id])
-        })
+      try {
+        var res = template(locals, handlebarsOpts)
+        self.async.done(function (values) {
+          Object.keys(values).forEach(function (id) {
+            res = res.replace(id, values[id])
+          })
 
-        cb(null, res)
-      })
+          cb(null, res)
+        })
+      } catch (err) {
+        err.message = filename + ': ' + err.message
+        cb(err)
+      }
 
       return
     }

test/3.x/app.js

@@ -140,7 +140,9 @@ before(function () {
   })
 
   app.get('/syntax-error', function (req, res) {
-    res.render('syntax-error')
+    res.render('syntax-error', {
+      cache: true
+    })
   })
 
   app.get('/partials', function (req, res) {
@@ -205,6 +207,14 @@ test('syntax error', function(done) {
     .end(done)
 });
 
+test('syntax error cached', function (done) {
+  request(app)
+    .get('/syntax-error')
+    .expect(500)
+    .expect(shouldHaveFirstLineEqual('Error: ' + path.join(__dirname, 'views', 'syntax-error.hbs') + ': Parse error on line 1:'))
+    .end(done)
+})
+
 test('escape for frontend', function(done) {
   request(app)
     .get('/escape')

test/4.x/app.js

@@ -139,7 +139,9 @@ before(function () {
   })
 
   app.get('/syntax-error', function (req, res) {
-    res.render('syntax-error')
+    res.render('syntax-error', {
+      cache: true
+    })
   })
 
   app.get('/partials', function (req, res) {
@@ -215,6 +217,14 @@ test('syntax error', function(done) {
     .end(done)
 });
 
+test('syntax error cached', function (done) {
+  request(app)
+    .get('/syntax-error')
+    .expect(500)
+    .expect(shouldHaveFirstLineEqual('Error: ' + path.join(__dirname, 'views', 'syntax-error.hbs') + ': Parse error on line 1:'))
+    .end(done)
+})
+
 test('escape for frontend', function(done) {
   request(app)
     .get('/escape')