tremor-cli/test: Refactor large parts of the test code.

This gets rid of one of the long functions mentioned in #20, makes the code more
readable, and (in the future) easier to test properly.

Signed-off-by: Mordecai Malignatus <mordecai@malignat.us>

tremor-cli/src/cli.yaml

@@ -96,9 +96,12 @@ subcommands:
             about: One of `all`, `api`, `bench`, `command`, `integration`, `rest`, or `unit`
             takes_value: true
             default_value: "all"
+            index: 1
         - PATH:
             about: The root test path
+            takes_value: true
             default_value: "tests"
+            index: 2
         - REPORT:
             about: Should generate a test report to specified path
             short: o

tremor-cli/src/report.rs

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use crate::test::kind::Kind;
 use crate::test::stats;
 use std::collections::HashMap;
 
@@ -24,7 +25,7 @@ pub(crate) struct TestRun {
     pub(crate) includes: Vec<String>,
     pub(crate) excludes: Vec<String>,
     pub(crate) reports: HashMap<String, Vec<TestReport>>,
-    pub(crate) stats: HashMap<String, stats::Stats>,
+    pub(crate) stats: HashMap<Kind, stats::Stats>,
 }
 
 /// A test report is the collection of test suites that