1 files changed, 61 insertions, 0 deletions
diff --git a/templates/assets/tether/src/js/abutment.js b/templates/assets/tether/src/js/abutment.js
new file mode 100644
index 0000000..9605635
--- /dev/null
+++ b/templates/assets/tether/src/js/abutment.js
@@ -0,0 +1,61 @@
+/* globals TetherBase */
+
+const {getBounds, updateClasses, defer} = TetherBase.Utils;
+
+TetherBase.modules.push({
+  position({top, left}) {
+    const {height, width} = this.cache('element-bounds', () => {
+      return getBounds(this.element);
+    });
+
+    const targetPos = this.getTargetBounds();
+
+    const bottom = top + height;
+    const right = left + width;
+
+    const abutted = [];
+    if (top <= targetPos.bottom && bottom >= targetPos.top) {
+      ['left', 'right'].forEach(side => {
+        const targetPosSide = targetPos[side];
+        if (targetPosSide === left || targetPosSide === right) {
+          abutted.push(side);
+        }
+      });
+    }
+
+    if (left <= targetPos.right && right >= targetPos.left) {
+      ['top', 'bottom'].forEach(side => {
+        const targetPosSide = targetPos[side];
+        if (targetPosSide === top || targetPosSide === bottom) {
+          abutted.push(side);
+        }
+      });
+    }
+
+    const allClasses = [];
+    const addClasses = [];
+
+    const sides = ['left', 'top', 'right', 'bottom'];
+    allClasses.push(this.getClass('abutted'));
+    sides.forEach(side => {
+      allClasses.push(`${ this.getClass('abutted') }-${ side }`);
+    });
+
+    if (abutted.length) {
+      addClasses.push(this.getClass('abutted'));
+    }
+
+    abutted.forEach(side => {
+      addClasses.push(`${ this.getClass('abutted') }-${ side }`);
+    });
+
+    defer(() => {
+      if (!(this.options.addTargetClasses === false)) {
+        updateClasses(this.target, addClasses, allClasses);
+      }
+      updateClasses(this.element, addClasses, allClasses);
+    });
+
+    return true;
+  }
+});