Better handling of negation in filterToMongoQuery

Similar to SQL, negating a null should still be null.

test/mongodb-functions.ts

@@ -1,13 +1,13 @@
 import ava from "ava";
 import * as mongodbFunctions from "../lib/mongodb-functions";
-import { stringify } from "../lib/common/expression-parser";
+import { stringify, parse } from "../lib/common/expression-parser";
 
-ava("mongoQueryToFilter", (t) => {
+ava("convertOldPrecondition", (t) => {
   const tests = [
     [{}, "true"],
     [{ test: "test" }, 'test = "test"'],
     [{ test: { $eq: "test" } }, 'test = "test"'],
-    [{ test: { $ne: "test" } }, 'test <> "test"'],
+    [{ test: { $ne: "test" } }, 'test <> "test" OR test IS NULL'],
     [{ test: { $gte: "test" } }, 'test >= "test"'],
     [{ "Tags.test": true }, "Tags.test IS NOT NULL"],
     [{ "Tags.test": false }, "Tags.test IS NULL"],
@@ -22,20 +22,20 @@ ava("mongoQueryToFilter", (t) => {
     [{ _tags: { $eq: "test" } }, "Tags.test IS NOT NULL"],
     [
       { $and: [{ test: "test" }, { test: { $ne: "test" } }] },
-      'test = "test" AND test <> "test"',
+      'test = "test" AND (test <> "test" OR test IS NULL)',
     ],
     [{ test: "test", test2: "test2" }, 'test = "test" AND test2 = "test2"'],
     [
       { $or: [{ test: "test" }, { test: { $ne: "test" } }] },
-      'test = "test" OR test <> "test"',
+      'test = "test" OR (test <> "test" OR test IS NULL)',
     ],
     [
       { test: { $gte: "test1", $ne: "test2" } },
-      'test >= "test1" AND test <> "test2"',
+      'test >= "test1" AND (test <> "test2" OR test IS NULL)',
     ],
     [
       { test: "test", test2: { $ne: "test2" } },
-      'test = "test" AND test2 <> "test2"',
+      'test = "test" AND (test2 <> "test2" OR test2 IS NULL)',
     ],
   ];
 
@@ -50,13 +50,83 @@ ava("mongoQueryToFilter", (t) => {
 
   t.plan(tests.length + 2 * shouldFailTests.length);
   for (const test of tests)
-    t.is(stringify(mongodbFunctions.mongoQueryToFilter(test[0])), test[1]);
+    t.is(stringify(mongodbFunctions.convertOldPrecondition(test[0])), test[1]);
 
   for (const test of shouldFailTests) {
     const func = (): void => {
-      mongodbFunctions.mongoQueryToFilter(test[0] as Record<string, unknown>);
+      mongodbFunctions.convertOldPrecondition(
+        test[0] as Record<string, unknown>
+      );
     };
     const error = t.throws(func, { instanceOf: Error });
     t.is(error.message, test[1]);
   }
 });
+
+ava("filterToMongoQuery", async (t) => {
+  const queries: [string, Record<string, unknown>][] = [
+    ["true", {}],
+    ["Tags.tag1 = true", { _tags: "tag1" }],
+    ["Tags.tag1 <> false", { _tags: "tag1" }],
+    ["Tags.tag1 IS NULL", { _tags: { $ne: "tag1" } }],
+    ["Tags.tag1 = 123", { "Tags.tag1": 123 }],
+    ["Param1 = 'value1'", { "Param1._value": "value1" }],
+    ["Param1 <> 'value1'", { "Param1._value": { $nin: ["value1", null] } }],
+    ["Param1 > 'value'", { "Param1._value": { $gt: "value" } }],
+    ["Param1 IS NOT NULL", { "Param1._value": { $ne: null } }],
+    ["Param1 LIKE 'value'", { "Param1._value": /^value$/ }],
+    ["LOWER(Param1) LIKE 'value'", { "Param1._value": /^value$/i }],
+    [
+      "Param1 <> 'value2' OR NOT (Param2 = 'value1' OR Param1 < 'value2')",
+      {
+        $or: [
+          { "Param1._value": { $nin: ["value2", null] } },
+          {
+            $and: [
+              { "Param2._value": { $nin: ["value1", null] } },
+              { "Param1._value": { $gte: "value2" } },
+            ],
+          },
+        ],
+      },
+    ],
+    [
+      "Param1 <> 'value2' OR Param1 IS NULL",
+      {
+        $or: [
+          { "Param1._value": { $nin: ["value2", null] } },
+          { "Param1._value": null },
+        ],
+      },
+    ],
+  ];
+
+  for (const [expStr, expect] of queries) {
+    const exp = parse(expStr);
+    const query = mongodbFunctions.filterToMongoQuery(
+      mongodbFunctions.processDeviceFilter(exp)
+    );
+    t.deepEqual(query, expect);
+  }
+
+  const failQueries: [any, string][] = [
+    ["Param1 = Param2", "Invalid RHS operand of = clause"],
+    ["Param1 LIKE Param2", "Invalid RHS operand of LIKE clause"],
+    ["1 LIKE '1'", "Invalid LHS operand of LIKE clause"],
+    ["1 = 2", "Invalid LHS operand of = clause"],
+    ["1 IS NULL", "Invalid LHS operand of IS NULL clause"],
+    ["false", "Primitives are not valid queries"],
+    ["UPPER(Param1) LIKE 'value'", "Invalid RHS operand of LIKE clause"],
+  ];
+
+  for (const [expStr, err] of failQueries) {
+    const exp = parse(expStr);
+    t.throws(
+      () =>
+        mongodbFunctions.filterToMongoQuery(
+          mongodbFunctions.processDeviceFilter(exp)
+        ),
+      { message: err }
+    );
+  }
+});