From 7b8c952d4cc0a5ea7a7238366e05e20a3afeb211 Mon Sep 17 00:00:00 2001
From: Chris Loer <chris.loer@gmail.com>
Date: Fri, 6 Jul 2018 15:23:14 -0700
Subject: [PATCH] Support collators in feature filter expressions. Fixes issue
 #6920: feature filters using collator expressions would incorrectly be
 treated as legacy filters.

---
 src/style-spec/feature_filter/index.js      |  3 +--
 test/unit/style-spec/feature_filter.test.js | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/style-spec/feature_filter/index.js b/src/style-spec/feature_filter/index.js
index d5baf8ab869..6138bf6e16c 100644
--- a/src/style-spec/feature_filter/index.js
+++ b/src/style-spec/feature_filter/index.js
@@ -28,7 +28,7 @@ function isExpressionFilter(filter: any) {
     case '>=':
     case '<':
     case '<=':
-        return filter.length === 3 && (Array.isArray(filter[1]) || Array.isArray(filter[2]));
+        return filter.length !== 3 || (Array.isArray(filter[1]) || Array.isArray(filter[2]));
 
     case 'any':
     case 'all':
@@ -153,4 +153,3 @@ function convertHasOp(property: string) {
 function convertNegation(filter: mixed) {
     return ['!', filter];
 }
-
diff --git a/test/unit/style-spec/feature_filter.test.js b/test/unit/style-spec/feature_filter.test.js
index 877e6de94ab..938bf736357 100644
--- a/test/unit/style-spec/feature_filter.test.js
+++ b/test/unit/style-spec/feature_filter.test.js
@@ -24,6 +24,19 @@ test('filter', (t) => {
         t.end();
     });
 
+    t.test('expression, collator comparison', (t) => {
+        const caseSensitive = filter(['==', ['string', ['get', 'x']], ['string', ['get', 'y']], ['collator', { 'case-sensitive': true }]]);
+        t.equal(caseSensitive({zoom: 0}, {properties: {x: 'a', y: 'b'}}), false);
+        t.equal(caseSensitive({zoom: 0}, {properties: {x: 'a', y: 'A'}}), false);
+        t.equal(caseSensitive({zoom: 0}, {properties: {x: 'a', y: 'a'}}), true);
+
+        const caseInsensitive = filter(['==', ['string', ['get', 'x']], ['string', ['get', 'y']], ['collator', { 'case-sensitive': false }]]);
+        t.equal(caseInsensitive({zoom: 0}, {properties: {x: 'a', y: 'b'}}), false);
+        t.equal(caseInsensitive({zoom: 0}, {properties: {x: 'a', y: 'A'}}), true);
+        t.equal(caseInsensitive({zoom: 0}, {properties: {x: 'a', y: 'a'}}), true);
+        t.end();
+    });
+
     t.test('expression, any/all', (t) => {
         t.equal(filter(['all'])(), true);
         t.equal(filter(['all', true])(), true);
@@ -52,7 +65,6 @@ test('filter', (t) => {
         t.end();
     });
 
-
     t.test('degenerate', (t) => {
         t.equal(filter()(), true);
         t.equal(filter(undefined)(), true);