From 4ab92b99adf17f54deddda07fb8820491f4dddca Mon Sep 17 00:00:00 2001
From: Chris Joel <cdata@google.com>
Date: Thu, 23 Jul 2015 15:49:01 -0700
Subject: [PATCH] Ignore non-primary mouse input.

---
 iron-button-state.html | 30 +++++++++++++++++++++++++++++-
 test/active-state.html |  9 +++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/iron-button-state.html b/iron-button-state.html
index fc52e17..11c03d7 100644
--- a/iron-button-state.html
+++ b/iron-button-state.html
@@ -91,6 +91,8 @@
       'space:keyup': '_spaceKeyUpHandler',
     },
 
+    _mouseEventRe: /^mouse/,
+
     _tapHandler: function() {
       if (this.toggles) {
        // a tap is needed to toggle the active state
@@ -111,7 +113,33 @@
       this.fire('change');
     },
 
-    _downHandler: function() {
+    _eventSourceIsPrimaryInput: function(event) {
+      event = event.detail.sourceEvent || event;
+
+      // Always true for non-mouse events....
+      if (!this._mouseEventRe.test(event.type)) {
+        return true;
+      }
+
+      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/buttons
+      if ('buttons' in event) {
+        return event.buttons === 1;
+      }
+
+      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/which
+      if (typeof event.which === 'number') {
+        return event.which < 2;
+      }
+
+      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/button
+      return event.button < 1;
+    },
+
+    _downHandler: function(event) {
+      if (!this._eventSourceIsPrimaryInput(event)) {
+        return;
+      }
+
       this._setPointerDown(true);
       this._setPressed(true);
       this._setReceivedFocusFromKeyboard(false);
diff --git a/test/active-state.html b/test/active-state.html
index bffa727..983df0e 100644
--- a/test/active-state.html
+++ b/test/active-state.html
@@ -41,6 +41,15 @@
         activeTarget = fixture('TrivialActiveState');
       });
 
+      suite('non-primary pointer input source', function() {
+        test('does not cause state to change', function() {
+          var rightClickMouseEvent = new CustomEvent('mousedown');
+          rightClickMouseEvent.buttons = 2;
+          activeTarget.dispatchEvent(rightClickMouseEvent);
+          expect(activeTarget.pressed).to.be.equal(false);
+        });
+      });
+
       suite('active state with toggles attribute', function() {
         setup(function() {
           activeTarget = fixture('ToggleActiveState');