Extract search_util.js module.

We probably should have done this a while ago, even
though these functions are pretty tiny.  The goal here
is to make it easier to have more consistent search
semantics.

Our first use case is subs.js.  In this case we
are able to decouple a bit of generic string
matching from the subs-specific code.

.eslintrc.json

@@ -102,6 +102,7 @@
         "Filter": false,
         "flatpickr": false,
         "pointer": false,
+        "search_util": false,
         "util": false,
         "rtl": false,
         "MessageListData": false,

frontend_tests/node_tests/subs.js

@@ -2,6 +2,8 @@ global.stub_out_jquery();
 
 set_global('ui', {});
 zrequire('stream_data');
+zrequire('search_util');
+
 global.patch_builtin('window', {
     location: {
         hash: "#streams/1/announce",

static/js/bundles/app.js

@@ -33,6 +33,7 @@ import "js/feature_flags.js";
 import "js/loading.js";
 import 'js/schema.js';
 import "js/util.js";
+import "js/search_util.js";
 import "js/keydown_util.js";
 import "js/lightbox_canvas.js";
 import "js/rtl.js";

static/js/search_util.js

@@ -0,0 +1,37 @@
+var search_util = (function () {
+
+var exports = {};
+
+exports.get_search_terms = function (input) {
+    var search_terms = input.toLowerCase().split(",").map(function (s) {
+        return s.trim();
+    });
+    return search_terms;
+};
+
+exports.vanilla_match = function (opts) {
+    /*
+        This is a pretty vanilla search criteria
+        where we see if any of our search terms
+        is in our value. When in doubt we should use
+        this for all Zulip filters, but we may
+        have more complicated use cases in some
+        places.
+
+        This is case insensitive.
+    */
+    var val = opts.val.toLowerCase();
+    return _.any(opts.search_terms, function (term) {
+        if (val.indexOf(term) !== -1) {
+            return true;
+        }
+    });
+};
+
+return exports;
+
+}());
+if (typeof module !== 'undefined') {
+    module.exports = search_util;
+}
+window.search_util = search_util;

static/js/subs.js

@@ -318,19 +318,14 @@ function remove_temporarily_miscategorized_streams() {
 exports.remove_miscategorized_streams = remove_temporarily_miscategorized_streams;
 
 function stream_matches_query(query, sub, attr) {
-    var search_terms = query.input.toLowerCase().split(",").map(function (s) {
-        return s.trim();
+    var search_terms = search_util.get_search_terms(query.input);
+    var val = sub[attr];
+
+    var flag = search_util.vanilla_match({
+        val: val,
+        search_terms: search_terms,
     });
 
-    var flag = true;
-    flag = flag && (function () {
-        var sub_attr = sub[attr].toLowerCase();
-        return _.any(search_terms, function (o) {
-            if (sub_attr.indexOf(o) !== -1) {
-                return true;
-            }
-        });
-    }());
     flag = flag && (sub.subscribed || !query.subscribed_only ||
                     sub.data_temp_view === "true");
     return flag;

tools/test-js-with-node

@@ -60,6 +60,7 @@ enforce_fully_covered = {
     'static/js/scroll_util.js',
     'static/js/search.js',
     'static/js/search_suggestion.js',
+    'static/js/search_util.js',
     # Removed because we're migrating code from uncovered other settings pages to here.
     # 'static/js/settings_ui.js',
     'static/js/settings_muting.js',