fix(adapter): don't duplicate multiline failure messages

The current code to handle removing error messages for formatting does not
properly handle multiline error messages and results in the message being
repeated at the top of the stack trace. The code only searched for the message
in the first stack line, which meant it would never be found because the message
was multiple lines, which meant that the message would be pre-pended by the
message not in stack logic.

The existing multiline test actually triggers this behavior, but because it used
toMatch it only verified that the message was included, not that it only existed
once.

src/adapter.js

@@ -82,12 +82,23 @@ function formatFailedStep (step) {
 
   // Remove the message prior to processing the stack to prevent issues like
   // https://github.com/karma-runner/karma-jasmine/issues/79
-  var stackframes = step.stack.split('\n')
+
+  // Jasmine filters empty newlines from the stack so remove them from the
+  // message before searching for it. Also, also remove the trailing newline (if
+  // present) so that when the message is put back on the top of the stack it
+  // doesn't introduce an extra newline.
+  var messageWithoutEmptyLines = step.message.replace(/\n+/g, '\n').replace(/\n$/, '')
+  var messageStartIndex = step.stack.indexOf(messageWithoutEmptyLines)
+  var firstNewlineIndex = step.stack.indexOf('\n')
   var messageOnStack = null
-  if (stackframes[0].indexOf(step.message) !== -1) {
+  var stack = step.stack
+  if (messageStartIndex !== -1 && messageStartIndex < firstNewlineIndex) {
     // Remove the message if it is in the stack string (eg Chrome)
-    messageOnStack = stackframes.shift()
+    messageOnStack = step.stack.substring(0, messageStartIndex + messageWithoutEmptyLines.length)
+    stack = step.stack.substring(messageStartIndex + messageWithoutEmptyLines.length)
   }
+
+  var stackframes = stack.split('\n')
   // Filter frames
   var relevantStackFrames = getRelevantStackFrom(stackframes)
   if (messageOnStack) {

test/adapter.spec.js

@@ -359,7 +359,7 @@ describe('jasmine adapter', function () {
         stack: '@file.js:123\n'
       }
 
-      expect(formatFailedStep(step)).toMatch(/^Jasmine fail message/)
+      expect(formatFailedStep(step)).toBe('Jasmine fail message\n@file.js:123')
     })
 
     it('should report message if no stack trace', function () {
@@ -383,6 +383,7 @@ describe('jasmine adapter', function () {
 
       expect(formatFailedStep(step)).toBe('MESSAGE\nsource/controller.js:45')
     })
+
     it('should properly format message containing new-line characters', function () {
       // FF does not have the message in the stack trace
 
@@ -392,7 +393,17 @@ describe('jasmine adapter', function () {
         stack: 'Error: Jasmine fail\nmessage\n@file.js:123'
       }
 
-      expect(formatFailedStep(step)).toMatch('Jasmine fail\nmessage\n@file.js:123')
+      expect(formatFailedStep(step)).toBe('Error: Jasmine fail\nmessage\n@file.js:123')
+    })
+
+    it('should properly format message containing repeated new-line characters', function () {
+      var step = {
+        passed: false,
+        message: 'Failed: 1. failure message\n\n\n2. another failure\n3. a third failure\n\n\n\n',
+        stack: 'Error: Failed: 1. failure message\n2. another failure\n3. a third failure\n    at <Jasmine>\n    at UserContext.<anonymous> (/base/jasmine/test.js:13:9)\n    at <Jasmine>'
+      }
+
+      expect(formatFailedStep(step)).toBe('Error: Failed: 1. failure message\n2. another failure\n3. a third failure\n    at <Jasmine>\n    at UserContext.<anonymous> (/base/jasmine/test.js:13:9)\n    at <Jasmine>')
     })
   })