From ef043c3b7bb64072dd796f147453eb279388f99c Mon Sep 17 00:00:00 2001
From: Josh Hawkins <josh.r.hawk@gmail.com>
Date: Thu, 7 Mar 2019 14:04:31 -0500
Subject: [PATCH 1/2] Expose date filter issue in a unit test

---
 packages/perspective/test/js/filters.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/packages/perspective/test/js/filters.js b/packages/perspective/test/js/filters.js
index 7f66f10510..12b44ae504 100644
--- a/packages/perspective/test/js/filters.js
+++ b/packages/perspective/test/js/filters.js
@@ -110,6 +110,23 @@ module.exports = perspective => {
                 view.delete();
                 table.delete();
             });
+
+            it("w < date as string", async function() {
+                const schema = {
+                    w: "date",
+                    x: "integer",
+                    y: "string",
+                    z: "boolean"
+                };
+                var table = perspective.table(schema);
+                var view = table.view({
+                    filter: [["w", "<", "10/01/2018"]]
+                });
+                let json = await view.to_json();
+                expect(json).toEqual([r_date_range_data[0]]);
+                view.delete();
+                table.delete();
+            });
         });
 
         describe("EQ", function() {

From 9d0ed3f7eaf4a2edfc466499f1f16fe793784dc0 Mon Sep 17 00:00:00 2001
From: Josh Hawkins <josh.r.hawk@gmail.com>
Date: Thu, 7 Mar 2019 16:32:58 -0500
Subject: [PATCH 2/2] Fix date filtering and add another test on <

---
 cpp/perspective/src/cpp/emscripten.cpp  |  3 +-
 packages/perspective/test/js/filters.js | 52 +++++++++++++++++--------
 2 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/cpp/perspective/src/cpp/emscripten.cpp b/cpp/perspective/src/cpp/emscripten.cpp
index d1f03ef1b9..63f45bd92a 100644
--- a/cpp/perspective/src/cpp/emscripten.cpp
+++ b/cpp/perspective/src/cpp/emscripten.cpp
@@ -167,7 +167,8 @@ namespace binding {
                             term = mktscalar(filter[2].as<bool>());
                         } break;
                         case DTYPE_DATE: {
-                            term = mktscalar(t_date(filter[2].as<std::int32_t>()));
+                            val parsed_date = j_date_parser.call<val>("parse", filter[2]);
+                            term = mktscalar(jsdate_to_t_date(parsed_date));
                         } break;
                         case DTYPE_TIME: {
                             val parsed_date = j_date_parser.call<val>("parse", filter[2]);
diff --git a/packages/perspective/test/js/filters.js b/packages/perspective/test/js/filters.js
index 12b44ae504..cb00771300 100644
--- a/packages/perspective/test/js/filters.js
+++ b/packages/perspective/test/js/filters.js
@@ -18,10 +18,10 @@ var rdata = [{w: +now, x: 1, y: "a", z: true}, {w: +now, x: 2, y: "b", z: false}
 
 // starting from 09/01/2018 to 12/01/2018
 var date_range_data = [
-    {w: new Date(1535778060000), x: 1, y: "a", z: true},
-    {w: new Date(1538370060000), x: 2, y: "b", z: false},
-    {w: new Date(1541048460000), x: 3, y: "c", z: true},
-    {w: new Date(1543644060000), x: 4, y: "d", z: false}
+    {w: new Date(1535778060000), x: 1, y: "a", z: true}, // Sat Sep 01 2018 01:01:00 GMT-0400
+    {w: new Date(1538370060000), x: 2, y: "b", z: false}, // Mon Oct 01 2018 01:01:00 GMT-0400
+    {w: new Date(1541048460000), x: 3, y: "c", z: true}, // Thu Nov 01 2018 01:01:00 GMT-0400
+    {w: new Date(1543644060000), x: 4, y: "d", z: false} // Sat Dec 01 2018 01:01:00 GMT-0500
 ];
 
 var r_date_range_data = [
@@ -111,21 +111,41 @@ module.exports = perspective => {
                 table.delete();
             });
 
-            it("w < date as string", async function() {
+            describe("filtering on date column", function() {
                 const schema = {
-                    w: "date",
-                    x: "integer",
-                    y: "string",
-                    z: "boolean"
+                    w: "date"
                 };
-                var table = perspective.table(schema);
-                var view = table.view({
-                    filter: [["w", "<", "10/01/2018"]]
+
+                const date_results = [
+                    {w: +new Date(1535760000000)}, // Fri Aug 31 2018 20:00:00 GMT-0400
+                    {w: +new Date(1538352000000)}, // Sun Sep 30 2018 20:00:00 GMT-0400
+                    {w: +new Date(1541030400000)}, // Wed Oct 31 2018 20:00:00 GMT-0400
+                    {w: +new Date(1543622400000)} // Fri Nov 30 2018 19:00:00 GMT-0500
+                ];
+
+                it("w > date as string", async function() {
+                    var table = perspective.table(schema);
+                    table.update(date_range_data);
+                    var view = table.view({
+                        filter: [["w", ">", "10/01/2018"]]
+                    });
+                    let json = await view.to_json();
+                    expect(json).toEqual(date_results.slice(2, 4));
+                    view.delete();
+                    table.delete();
+                });
+
+                it("w < date as string", async function() {
+                    var table = perspective.table(schema);
+                    table.update(date_range_data);
+                    var view = table.view({
+                        filter: [["w", "<", "10/01/2018"]]
+                    });
+                    let json = await view.to_json();
+                    expect(json).toEqual([date_results[0]]);
+                    view.delete();
+                    table.delete();
                 });
-                let json = await view.to_json();
-                expect(json).toEqual([r_date_range_data[0]]);
-                view.delete();
-                table.delete();
             });
         });