terminal: resize handles increased styles/graphemes

src/terminal/PageList.zig

@@ -537,9 +537,6 @@ fn resizeCols(
 ) !void {
     assert(cols != self.cols);
 
-    // Our new capacity, ensure we can fit the cols
-    const cap = try std_capacity.adjust(.{ .cols = cols });
-
     // If we have a cursor position (x,y), then we try under any col resizing
     // to keep the same number remaining active rows beneath it. This is a
     // very special case if you can imagine clearing the screen (i.e.
@@ -588,7 +585,7 @@ fn resizeCols(
         // Note: we can do a fast-path here if all of our rows in this
         // page already fit within the new capacity. In that case we can
         // do a non-reflow resize.
-        try self.reflowPage(cap, chunk.page);
+        try self.reflowPage(cols, chunk.page);
     }
 
     // If our total rows is less than our active rows, we need to grow.
@@ -774,7 +771,7 @@ const ReflowCursor = struct {
 /// function.
 fn reflowPage(
     self: *PageList,
-    cap: Capacity,
+    cols: size.CellCountInt,
     initial_node: *List.Node,
 ) !void {
     // The cursor tracks where we are in the source page.
@@ -810,6 +807,10 @@ fn reflowPage(
     // Our new capacity when growing columns may also shrink rows. So we
     // need to do a loop in order to potentially make multiple pages.
     dst_loop: while (true) {
+        // Our cap is based on the source page cap so we can inherit
+        // potentially increased styles/graphemes/etc.
+        const cap = try src_cursor.page.capacity.adjust(.{ .cols = cols });
+
         // Create our new page and our cursor restarts at 0,0 in the new page.
         // The new page always starts with a size of 1 because we know we have
         // at least one row to copy from the src.

src/terminal/Terminal.zig

@@ -7728,6 +7728,27 @@ test "Terminal: resize with high unique style per cell" {
     try t.resize(alloc, 60, 30);
 }
 
+test "Terminal: resize with high unique style per cell with wrapping" {
+    const alloc = testing.allocator;
+    var t = try init(alloc, 30, 30);
+    defer t.deinit(alloc);
+
+    const cell_count: u16 = @intCast(t.rows * t.cols);
+    for (0..cell_count) |i| {
+        const r: u8 = @intCast(i >> 8);
+        const g: u8 = @intCast(i & 0xFF);
+
+        try t.setAttribute(.{ .direct_color_bg = .{
+            .r = r,
+            .g = g,
+            .b = 0,
+        } });
+        try t.print('x');
+    }
+
+    try t.resize(alloc, 60, 30);
+}
+
 test "Terminal: DECCOLM without DEC mode 40" {
     const alloc = testing.allocator;
     var t = try init(alloc, 5, 5);