fix empty not show when not columns

Author: zombieJ

examples/debug.tsx

@@ -120,11 +120,11 @@ const Demo = () => {
     }
   }, []);
 
-  const [_, forceUpdate] = React.useState();
+  const [, forceUpdate] = React.useState();
 
   return (
     <div>
-      <h2>simple table</h2>
+      <h2>Debug Usage, remove after stable released</h2>
       <button type="button" onClick={addData}>
         Add Row
       </button>
@@ -148,6 +148,8 @@ const Demo = () => {
         <Column dataIndex="date" colSpan={0} />
       </Table>
 
+      <Table<RecordType> />
+
       <button
         type="button"
         onClick={() => {

src/hooks/useColumns.tsx

@@ -151,10 +151,23 @@ function useColumns<RecordType>(
     return baseColumns;
   }, [expandable, baseColumns, getRowKey, expandedKeys, expandIcon]);
 
-  const mergedColumns = React.useMemo(
-    () => (transformColumns ? transformColumns(withExpandColumns) : withExpandColumns),
-    [transformColumns, withExpandColumns],
-  );
+  const mergedColumns = React.useMemo(() => {
+    let finalColumns = withExpandColumns;
+    if (transformColumns) {
+      finalColumns = transformColumns(finalColumns);
+    }
+
+    // Always provides at least one column for table display
+    if (!finalColumns.length) {
+      finalColumns = [
+        {
+          render: () => null,
+        },
+      ];
+    }
+
+    return finalColumns;
+  }, [transformColumns, withExpandColumns]);
 
   const flattenColumns = React.useMemo(() => flatColumns(mergedColumns), [mergedColumns]);
 

tests/Table.spec.js

@@ -11,14 +11,21 @@ describe('Table.Basic', () => {
     return <Table columns={columns} data={data} {...props} />;
   };
 
-  it('renders correctly', () => {
-    const wrapper = mount(
-      createTable({
-        prefixCls: 'test-prefix',
-        className: 'test-class-name',
-      }),
-    );
-    expect(wrapper.render()).toMatchSnapshot();
+  describe('renders correctly', () => {
+    it('basic', () => {
+      const wrapper = mount(
+        createTable({
+          prefixCls: 'test-prefix',
+          className: 'test-class-name',
+        }),
+      );
+      expect(wrapper.render()).toMatchSnapshot();
+    });
+
+    it('no columns', () => {
+      const wrapper = mount(createTable({ columns: [] }));
+      expect(wrapper.render()).toMatchSnapshot();
+    });
   });
 
   it('renders empty text correctly', () => {

tests/__snapshots__/Table.spec.js.snap

@@ -308,7 +308,7 @@ exports[`Table.Basic renders colSpan correctly 1`] = `
 </div>
 `;
 
-exports[`Table.Basic renders correctly 1`] = `
+exports[`Table.Basic renders correctly basic 1`] = `
 <div
   class="test-prefix test-class-name"
 >
@@ -361,6 +361,53 @@ exports[`Table.Basic renders correctly 1`] = `
 </div>
 `;
 
+exports[`Table.Basic renders correctly no columns 1`] = `
+<div
+  class="rc-table"
+>
+  <div
+    class="rc-table-container"
+  >
+    <div
+      class="rc-table-content"
+    >
+      <table
+        style="table-layout: auto;"
+      >
+        <colgroup>
+          <col />
+        </colgroup>
+        <thead>
+          <tr>
+            <th
+              class="rc-table-cell"
+            />
+          </tr>
+        </thead>
+        <tbody
+          class="rc-table-tbody"
+        >
+          <tr
+            class="rc-table-row rc-table-row-level-0"
+          >
+            <td
+              class="rc-table-cell"
+            />
+          </tr>
+          <tr
+            class="rc-table-row rc-table-row-level-0"
+          >
+            <td
+              class="rc-table-cell"
+            />
+          </tr>
+        </tbody>
+      </table>
+    </div>
+  </div>
+</div>
+`;
+
 exports[`Table.Basic renders rowSpan correctly 1`] = `
 <div
   class="rc-table"