Add fix to avoid exception on Rows with no children

src/Spectre.Console/Widgets/Rows.cs

@@ -37,10 +37,15 @@ protected override Measurement Measure(RenderOptions options, int maxWidth)
         }
         else
         {
-            var measurements = _children.Select(c => c.Measure(options, maxWidth));
-            return new Measurement(
-                measurements.Min(c => c.Min),
-                measurements.Min(c => c.Max));
+            var measurements = _children.Select(c => c.Measure(options, maxWidth)).ToArray();
+            if (measurements.Length > 0)
+            {
+                return new Measurement(
+                    measurements.Min(c => c.Min),
+                    measurements.Min(c => c.Max));
+            }
+
+            return new Measurement(0, 0);
         }
     }
 

test/Spectre.Console.Tests/Expectations/Widgets/Rows/Render_Empty.Output.verified.txt

@@ -0,0 +1,6 @@
+┌─────────────┬─────┐
+│ Foo         │ Bar │
+├─────────────┼─────┤
+│ HELLO WORLD │     │
+│             │ Qux │
+└─────────────┴─────┘

test/Spectre.Console.Tests/Spectre.Console.Tests.csproj

@@ -12,6 +12,9 @@
     <EmbeddedResource Include="Data\starwars.flf" />
     <None Remove="Data\poison.flf" />
     <EmbeddedResource Include="Data\poison.flf" />
+    <None Update="Expectations\Widgets\Rows\Render_Empty.Output.verified.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 
   <ItemGroup>

test/Spectre.Console.Tests/Unit/Widgets/RowsTests.cs

@@ -50,6 +50,25 @@ public Task Should_Render_Rows_Correctly_Inside_Other_Widget()
         return Verifier.Verify(console.Output);
     }
 
+    [Fact]
+    [Expectation("Render_Empty")]
+    public Task Should_Not_Throw_Exception_On_Empty_Rows()
+    {
+        // Given
+        var console = new TestConsole().Width(60);
+        var table = new Table()
+            .AddColumns("Foo", "Bar")
+            .AddRow("HELLO WORLD")
+            .AddRow(
+                new Rows(), new Text("Qux"));
+
+        // When
+        console.Write(table);
+
+        // Then
+        return Verifier.Verify(console.Output);
+    }
+
     [Fact]
     [Expectation("Render_Expanded_And_Nested")]
     public Task Should_Render_Rows_Correctly_Inside_Other_Widget_When_Expanded()