Improving TAPL error messages

Test: forrest
Bug: 187761685
Change-Id: I822f3f28e7153028fb5746e037066153478ec86d
diff --git a/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java b/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
index 3dff01e..fdbae54 100644
--- a/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
+++ b/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
@@ -445,11 +445,10 @@
 
             if (systemHealth != null) {
                 return message
-                        + ",\nperhaps linked to system health problems:\n<<<<<<<<<<<<<<<<<<\n"
+                        + ";\nPerhaps linked to system health problems:\n<<<<<<<<<<<<<<<<<<\n"
                         + systemHealth + "\n>>>>>>>>>>>>>>>>>>";
             }
         }
-
         return message;
     }
 
@@ -460,7 +459,7 @@
             if (checkEvents) {
                 final String eventMismatch = eventChecker.verify(0, false);
                 if (eventMismatch != null) {
-                    message = message + ", having produced " + eventMismatch;
+                    message = message + ";\n" + eventMismatch;
                 }
             } else {
                 eventChecker.finishNoWait();
@@ -497,12 +496,13 @@
     private void fail(String message) {
         checkForAnomaly();
         Assert.fail(formatSystemHealthMessage(formatErrorWithEvents(
-                "http://go/tapl : " + getContextDescription() + message
-                        + " (visible state: " + getVisibleStateMessage() + ")", true)));
+                "http://go/tapl test failure:\nOverview: " + getContextDescription()
+                        + " - visible state is " + getVisibleStateMessage()
+                        + ";\nDetails: " + message, true)));
     }
 
     private String getContextDescription() {
-        return mDiagnosticContext.isEmpty() ? "" : String.join(", ", mDiagnosticContext) + "; ";
+        return mDiagnosticContext.isEmpty() ? "" : String.join(", ", mDiagnosticContext);
     }
 
     void assertTrue(String message, boolean condition) {
diff --git a/tests/tapl/com/android/launcher3/tapl/LogEventChecker.java b/tests/tapl/com/android/launcher3/tapl/LogEventChecker.java
index ab6465c..a809e2e 100644
--- a/tests/tapl/com/android/launcher3/tapl/LogEventChecker.java
+++ b/tests/tapl/com/android/launcher3/tapl/LogEventChecker.java
@@ -115,7 +115,7 @@
             }
         }
 
-        return hasMismatches ? "mismatching events: " + sb.toString() : null;
+        return hasMismatches ? "Mismatching events: " + sb.toString() : null;
     }
 
     // If the list of actual events matches the list of expected events, returns -1, otherwise