Add note about tests logs & logging level, re-organised in sections

1 files changed, 20 insertions, 6 deletions

diff --git a/tests/README.md b/tests/README.md
index 313e2f2970..32f4da46dc 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -119,22 +119,36 @@ See [tests/README.testing-data.md](https://github.com/piwik/piwik/blob/master/te
 
 See [tests/README.screenshots.md](https://github.com/piwik/piwik/blob/master/tests/README.screenshots.md)
 
-## Profiling
-
-See [tests/README.xhprof.md](https://github.com/piwik/piwik/blob/master/tests/README.xhprof.md) for help on how to profile Piwik with XHProf.
+## Build artifacts
+### Test logs on CI
 
-## Benchmarks
+By default tests running on Travis CI will log all messages of at least `INFO` level in `$PIWIK_ROOT_DIR/tmp/logs/piwik.log`. In a given travis build output, you can view the logs by clicking on the line `$ cat $PIWIK_ROOT_DIR/tmp/logs/piwik.log` at the end of the build output text.
 
-See [tests/PHPUnit/Benchmarks/README.md](https://github.com/piwik/piwik/blob/master/tests/PHPUnit/Benchmarks/README.md) to learn about running Benchmark tests.
+Note: `DEBUG` and `VERBOSE` messages are not logged by default (to keep Travis page loading fast). At any time you can temporarirly enable logging by [modifying this file](https://github.com/piwik/piwik/blob/master/tests/PHPUnit/config.ini.travis.php#L23-27) and changing `log_level = info` to `log_level = debug` or `log_level = verbose`.
 
-## Build artifacts
+### Build artifacts
 
 You can retrieve the files generated during the build (the build artifacts) at [builds-artifacts.piwik.org](http://builds-artifacts.piwik.org/)
 
+### Screenshot tests build artifacts
+
+The screenshot tests generated by the continuous integration server are uploaded in [builds-artifacts.piwik.org/ui-tests.master/](http://builds-artifacts.piwik.org/ui-tests.master/?C=M;O=D)
+
 ## Troubleshooting
 
 See [tests/README.troubleshooting.md](https://github.com/piwik/piwik/blob/master/tests/README.troubleshooting.md) for troubleshooting the tests.
 
+## Advanced users
+### Benchmarks
+
+See [tests/PHPUnit/Benchmarks/README.md](https://github.com/piwik/piwik/blob/master/tests/PHPUnit/Benchmarks/README.md) to learn about running Benchmark tests.
+
+### Profiling
+
+See [tests/README.xhprof.md](https://github.com/piwik/piwik/blob/master/tests/README.xhprof.md) for help on how to profile Piwik with XHProf.
+
+
+
 ## Participate
 
 You can help by improving existing tests, or identify some missing tests and implement them.