In Gradle 1.0, the build displays the test report location as a fully qualified directory, but ends it with a period. When Jenkins sends the failure email, it replaces the project directory with the project URL, but keeps the final period, resulting in a link that doesn't work. It would also be nice if Jenkins could add "/index.html" to the end of the URL it sends for quick access to the HTML file.
Gradle 1.1 (release candidate 1 was released today) changes the report directory to the actual filename, but it displays it as a URL that starts with file://. According to http://forums.gradle.org/gradle/topics/whats_new_in_gradle_1_1_test_logging, this is so that Mac users can click on it and go directly to the file. For Jenkins users, this will result in URLs that look like "file://<http://myhost:80880/path-to-index.html", which won't work. I added the quotes, but not the "<", which jenkins put in the url.