test(container): rectangle color filling

src/container.zig

@@ -154,6 +154,138 @@ pub const Rectangle = packed struct {
             }
         }
     }
+
+    test "fill color overwrite parent fill" {
+        const event = @import("event.zig");
+        const testing = @import("testing.zig");
+
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .green },
+        }, .{});
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{}, .{}));
+        defer container.deinit();
+
+        try testing.expectContainerScreen(.{
+            .rows = 20,
+            .cols = 30,
+        }, &container, @import("test/container/rectangle_with_parent_fill_without_padding.zon"));
+    }
+
+    test "fill color padding to show parent fill" {
+        const event = @import("event.zig");
+        const testing = @import("testing.zig");
+
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+            .layout = .{
+                .padding = .all(2),
+            },
+            .rectangle = .{ .fill = .green },
+        }, .{});
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{}, .{}));
+        defer container.deinit();
+
+        try testing.expectContainerScreen(.{
+            .rows = 20,
+            .cols = 30,
+        }, &container, @import("test/container/rectangle_with_parent_padding.zon"));
+    }
+
+    test "fill color spacer with padding" {
+        const event = @import("event.zig");
+        const testing = @import("testing.zig");
+
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+            .rectangle = .{
+                .fill = .black,
+            },
+            .layout = .{
+                .padding = .vertical(2),
+                .direction = .vertical,
+            },
+        }, .{});
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{}, .{}));
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        defer container.deinit();
+
+        try testing.expectContainerScreen(.{
+            .rows = 20,
+            .cols = 30,
+        }, &container, @import("test/container/rectangle_with_padding.zon"));
+    }
+
+    test "fill color with gap" {
+        const event = @import("event.zig");
+        const testing = @import("testing.zig");
+
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+            .rectangle = .{
+                .fill = .black,
+            },
+            .layout = .{
+                .padding = .vertical(1),
+                .gap = 1,
+                .direction = .vertical,
+            },
+        }, .{});
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .blue },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        defer container.deinit();
+
+        try testing.expectContainerScreen(.{
+            .rows = 20,
+            .cols = 30,
+        }, &container, @import("test/container/rectangle_with_gap.zon"));
+    }
+
+    test "fill color with separator" {
+        const event = @import("event.zig");
+        const testing = @import("testing.zig");
+
+        var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+            .rectangle = .{
+                .fill = .black,
+            },
+            .layout = .{
+                .padding = .vertical(1),
+                .separator = .{
+                    .enabled = true,
+                },
+            },
+        }, .{});
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .blue },
+        }, .{}));
+        try container.append(try .init(std.testing.allocator, .{
+            .rectangle = .{ .fill = .white },
+        }, .{}));
+        defer container.deinit();
+
+        try testing.expectContainerScreen(.{
+            .rows = 20,
+            .cols = 30,
+        }, &container, @import("test/container/rectangle_with_seperator.zon"));
+    }
 };
 
 /// Layout configuration struct