more testing

sql-js · lovasoa · Sep 8, 2022 · Jul 3, 2020 · Sep 5, 2022 · Sep 5, 2022
commit ba733ba041c04c38ba4b1cb08098172e74c964ce
diff --git a/test/test_aggregate_functions.js b/test/test_aggregate_functions.js
@@ -2,16 +2,54 @@ exports.test = function (SQL, assert) {
     var db = new SQL.Database();
 
     db.create_aggregate(
-        "js_sum",
+        "sum",
         function () { return { sum: 0 }; },
         function (state, value) { state.sum += value; },
         function (state) { return state.sum; }
     );
 
     db.exec("CREATE TABLE test (col);");
     db.exec("INSERT INTO test VALUES (1), (2), (3);");
-    var result = db.exec("SELECT js_sum(col) FROM test;");
+    var result = db.exec("SELECT sum(col) FROM test;");
     assert.equal(result[0].values[0][0], 6, "Simple aggregate function.");
 
-    // TODO: Add test cases..
-}
+    db.create_aggregate(
+        "percentile",
+        function () { return { vals: [], pctile: null }; }, // init
+        function (state, value, pctile) {
+            state.vals.push(value);
+        },
+        function (state) {
+            return percentile(state.vals, state.pctile);
+        }
+    );
+    var result = db.exec("SELECT percentile(col, 20) FROM test;");
+    assert.equal(result[0].values[0][0], 1, "Aggregate function with two args");
+
+    db.create_aggregate(
+        "json_agg",
+        function() { return { vals: [] }; },
+        function(state, val) { state.vals.push(val); },
+        function(state) { return JSON.stringify(state.vals); }
+    );
+
+    db.exec("CREATE TABLE test2 (col, col2);");
+    db.exec("INSERT INTO test2 values ('four score', 12), ('and seven', 7), ('years ago', 1);");
+    var result = db.exec("SELECT json_agg(col) FROM test2;");
+    assert.deepEqual(JSON.parse(result[0].values[0]), ["four score", "and seven", "years ago"], "Aggregate function that returns JSON");
+}
+
+// helper function to calculate a percentile from an array. Will modify the
+// array in-place.
+function percentile(arr, p) {
+    arr.sort();
+    const pos = (arr.length - 1) * (p / 100);
+    const base = Math.floor(pos);
+    const rest = pos - base;
+    if (arr[base + 1] !== undefined) {
+        return arr[base] + rest * (arr[base + 1] - arr[base]);
+    } else {
+        return arr[base];
+    }
+};
+