Retrieve feature-based results for Test262 runs (#1980)

This Pull Request fixes/closes #1645.

It changes the following:

- Add `features` field to `SuiteResult` structure
- Fetch features from `TestSuite` and propagate them via `SuiteResult`
- Add `FeaturesInfo` structure and serialize it to `features.json`

boa_tester/src/exec/mod.rs

@@ -43,6 +43,13 @@ impl TestSuite {
                 .collect()
         };
 
+        let mut features = Vec::new();
+        for test_iter in self.tests.iter() {
+            for feature_iter in test_iter.features.iter() {
+                features.push(feature_iter.to_string());
+            }
+        }
+
         if verbose != 0 {
             println!();
         }
@@ -67,6 +74,7 @@ impl TestSuite {
             passed += suite.passed;
             ignored += suite.ignored;
             panic += suite.panic;
+            features.append(&mut suite.features.clone());
         }
 
         if verbose != 0 {
@@ -95,6 +103,7 @@ impl TestSuite {
             panic,
             suites,
             tests,
+            features,
         }
     }
 }

boa_tester/src/main.rs

@@ -357,6 +357,9 @@ struct SuiteResult {
     #[serde(rename = "t")]
     #[serde(skip_serializing_if = "Vec::is_empty", default)]
     tests: Vec<TestResult>,
+    #[serde(rename = "f")]
+    #[serde(skip_serializing_if = "Vec::is_empty", default)]
+    features: Vec<String>,
 }
 
 /// Outcome of a test.

boa_tester/src/results.rs

@@ -50,12 +50,45 @@ impl From<ResultInfo> for ReducedResultInfo {
     }
 }
 
+#[derive(Debug, Clone, Deserialize, Serialize)]
+struct FeaturesInfo {
+    #[serde(rename = "c")]
+    commit: Box<str>,
+    #[serde(rename = "u")]
+    test262_commit: Box<str>,
+    #[serde(rename = "n")]
+    suite_name: Box<str>,
+    #[serde(rename = "f")]
+    features: Vec<String>,
+}
+
+fn remove_duplicates(features_vec: &[String]) -> Vec<String> {
+    let mut result = features_vec.to_vec();
+    result.sort();
+    result.dedup();
+    result
+}
+
+impl From<ResultInfo> for FeaturesInfo {
+    fn from(info: ResultInfo) -> Self {
+        Self {
+            commit: info.commit,
+            test262_commit: info.test262_commit,
+            suite_name: info.results.name,
+            features: remove_duplicates(&info.results.features),
+        }
+    }
+}
+
 /// File name of the "latest results" JSON file.
 const LATEST_FILE_NAME: &str = "latest.json";
 
 /// File name of the "all results" JSON file.
 const RESULTS_FILE_NAME: &str = "results.json";
 
+/// File name of the "features" JSON file.
+const FEATURES_FILE_NAME: &str = "features.json";
+
 /// Writes the results of running the test suite to the given JSON output file.
 ///
 /// It will append the results to the ones already present, in an array.
@@ -108,14 +141,33 @@ pub(crate) fn write_json(
             Vec::new()
         };
 
-        all_results.push(new_results.into());
+        all_results.push(new_results.clone().into());
 
         let output = BufWriter::new(fs::File::create(&all_path)?);
         serde_json::to_writer(output, &all_results)?;
 
         if verbose != 0 {
             println!("Results written correctly");
         }
+
+        // Write the full list of features, existing features go first.
+
+        let features_path = path.join(FEATURES_FILE_NAME);
+
+        let mut all_features: Vec<FeaturesInfo> = if features_path.exists() {
+            serde_json::from_reader(BufReader::new(fs::File::open(&features_path)?))?
+        } else {
+            Vec::new()
+        };
+
+        all_features.push(new_results.into());
+
+        let features_output = BufWriter::new(fs::File::create(&features_path)?);
+        serde_json::to_writer(features_output, &all_features)?;
+
+        if verbose != 0 {
+            println!("Features written correctly");
+        }
     }
 
     Ok(())