diff --git a/src/components/Splitpanes.vue b/src/components/Splitpanes.vue
index ac5595c..c61e163 100644
--- a/src/components/Splitpanes.vue
+++ b/src/components/Splitpanes.vue
@@ -30,7 +30,7 @@
         ]"
       >
         <div
-          v-if="after.max === 100  && after.size > 0"
+          v-if="after.max === 100 && after.size > 0"
           class="toggle-btn"
           @click="togglePane(paneBefore)"
         >
diff --git a/tests/unit/components/Splitpanes.spec.js b/tests/unit/components/Splitpanes.spec.js
new file mode 100644
index 0000000..a39bf5e
--- /dev/null
+++ b/tests/unit/components/Splitpanes.spec.js
@@ -0,0 +1,141 @@
+import { expect } from 'chai'
+import { shallowMount } from '@vue/test-utils'
+import Splitpanes from '@/components/Splitpanes.vue'
+
+describe('Splitpanes.vue', () => {
+  it('renders correctly - vertical', () => {
+    // mount the component
+    const wrapper = shallowMount(Splitpanes, {
+      slots: {
+        leftPane: '<div />',
+        rightPane: '<div />'
+      },
+      propsData: {
+        before: { size: 60, max: 100 },
+        after: { size: 40, max: 100 }
+      }
+    })
+    
+    
+    expect(wrapper.findAll('.splitpanes-pane')).to.have.lengthOf(2)
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('60%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.width).to.equal('40%')
+  })
+
+  it('renders correctly - horizontal', () => {
+    // mount the component
+    const wrapper = shallowMount(Splitpanes, {
+      slots: {
+        leftPane: '<div />',
+        rightPane: '<div />'
+      },
+      propsData: {
+        before: { size: 60, max: 100 },
+        after: { size: 40, max: 100 },
+        horizontal: true
+      }
+    })
+    
+    
+    expect(wrapper.findAll('.splitpanes-pane')).to.have.lengthOf(2)
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.height).to.equal('60%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.height).to.equal('40%')
+  })
+
+  it('toggles correctly', async () => {
+    // mount the component
+    const wrapper = shallowMount(Splitpanes, {
+      slots: {
+        leftPane: '<div />',
+        rightPane: '<div />'
+      },
+      propsData: {
+        before: { size: 60, max: 100 },
+        after: { size: 40, max: 100 }
+      }
+    })
+    
+    await wrapper.find('.toggle-btn').trigger('click')
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('0%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.width).to.equal('100%')
+
+    await wrapper.find('.toggle-btn').trigger('click')
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('60%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.width).to.equal('40%')
+
+    await wrapper.findAll('.toggle-btn').at(1).trigger('click')
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('100%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.width).to.equal('0%')
+
+    await wrapper.find('.toggle-btn').trigger('click')
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('60%')
+    expect(wrapper.findAll('.splitpanes-pane').at(1).element.style.width).to.equal('40%')
+  })
+
+  it('drag - vertical', async () => {
+    const root = document.createElement('div')
+    const place = document.createElement('div')
+    root.style.width = '600px'
+    root.style.height = '500px'
+    root.appendChild(place)
+    document.body.appendChild(root)
+    
+    // mount the component
+    const wrapper = shallowMount(Splitpanes, {
+      attachTo: place,
+      slots: {
+        leftPane: '<div />',
+        rightPane: '<div />'
+      },
+      propsData: {
+        before: { size: 60, max: 100 },
+        after: { size: 40, max: 100 }
+      }
+    })
+    
+    await wrapper.find('.splitpanes-splitter').trigger('mousedown')
+    document.dispatchEvent(new MouseEvent("mousemove", {
+      clientX: 300,
+      clientY: 80
+    }))
+    document.dispatchEvent(new MouseEvent("mouseup"))
+    await wrapper.vm.$nextTick()
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.width).to.equal('50%')
+    wrapper.destroy()
+    root.remove()
+  })
+
+  it('drag - horizontal', async () => {
+    const root = document.createElement('div')
+    const place = document.createElement('div')
+    root.style.width = '600px'
+    root.style.height = '500px'
+    root.appendChild(place)
+    document.body.appendChild(root)
+    
+    // mount the component
+    const wrapper = shallowMount(Splitpanes, {
+      attachTo: place,
+      slots: {
+        leftPane: '<div />',
+        rightPane: '<div />'
+      },
+      propsData: {
+        before: { size: 10, max: 100 },
+        after: { size: 90, max: 100 },
+        horizontal: true
+      }
+    })
+    
+    await wrapper.find('.splitpanes-splitter').trigger('mousedown')
+    document.dispatchEvent(new MouseEvent("mousemove", {
+      clientX: 10,
+      clientY: 250
+    }))
+    document.dispatchEvent(new MouseEvent("mouseup"))
+    await wrapper.vm.$nextTick()
+    expect(wrapper.findAll('.splitpanes-pane').at(0).element.style.height).to.equal('50%')
+    wrapper.destroy()
+    root.remove()
+  })
+})