[new feature] TreeSelect: support string type of height prop (#4107)

src/tree-select/test/__snapshots__/index.spec.js.snap

@@ -15,3 +15,10 @@ exports[`empty list 1`] = `
   <div class="van-tree-select__content"></div>
 </div>
 `;
+
+exports[`height prop 1`] = `
+<div class="van-tree-select" style="height: 100vh;">
+  <div class="van-tree-select__nav"></div>
+  <div class="van-tree-select__content"></div>
+</div>
+`;

src/tree-select/test/index.spec.js

@@ -141,3 +141,13 @@ test('content slot', () => {
 
   expect(wrapper).toMatchSnapshot();
 });
+
+test('height prop', () => {
+  const wrapper = mount(TreeSelect, {
+    propsData: {
+      height: '100vh'
+    }
+  });
+
+  expect(wrapper).toMatchSnapshot();
+});