clearHistory

src/terminal/Screen.zig

@@ -541,6 +541,19 @@ fn maxCapacity(self: Screen) usize {
     return (self.rows + self.max_scrollback) * (self.cols + 1);
 }
 
+/// Clear all the history. This moves the viewport back to the "top", too.
+pub fn clearHistory(self: *Screen) void {
+    // If there is no history, do nothing.
+    if (self.history == 0) return;
+
+    // Delete all our history
+    self.storage.deleteOldest(self.history * (self.cols + 1));
+    self.history = 0;
+
+    // Back to the top
+    self.viewport = 0;
+}
+
 /// Scroll behaviors for the scroll function.
 pub const Scroll = union(enum) {
     /// Scroll to the top of the scroll buffer. The first line of the
@@ -1601,6 +1614,64 @@ test "Screen: row copy" {
     try testing.expectEqualStrings("2EFGH\n3IJKL\n2EFGH", contents);
 }
 
+test "Screen: clear history with no history" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var s = try init(alloc, 3, 5, 3);
+    defer s.deinit();
+    try s.testWriteString("4ABCD\n5EFGH\n6IJKL");
+    try testing.expect(s.viewportIsBottom());
+    s.clearHistory();
+    try testing.expect(s.viewportIsBottom());
+    {
+        // Test our contents rotated
+        var contents = try s.testString(alloc, .viewport);
+        defer alloc.free(contents);
+        try testing.expectEqualStrings("4ABCD\n5EFGH\n6IJKL", contents);
+    }
+    {
+        // Test our contents rotated
+        var contents = try s.testString(alloc, .screen);
+        defer alloc.free(contents);
+        try testing.expectEqualStrings("4ABCD\n5EFGH\n6IJKL", contents);
+    }
+}
+
+test "Screen: clear history" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var s = try init(alloc, 3, 5, 3);
+    defer s.deinit();
+    try s.testWriteString("1ABCD\n2EFGH\n3IJKL\n4ABCD\n5EFGH\n6IJKL");
+    try testing.expect(s.viewportIsBottom());
+
+    // Scroll to top
+    try s.scroll(.{ .top = {} });
+    {
+        // Test our contents rotated
+        var contents = try s.testString(alloc, .viewport);
+        defer alloc.free(contents);
+        try testing.expectEqualStrings("1ABCD\n2EFGH\n3IJKL", contents);
+    }
+
+    s.clearHistory();
+    try testing.expect(s.viewportIsBottom());
+    {
+        // Test our contents rotated
+        var contents = try s.testString(alloc, .viewport);
+        defer alloc.free(contents);
+        try testing.expectEqualStrings("4ABCD\n5EFGH\n6IJKL", contents);
+    }
+    {
+        // Test our contents rotated
+        var contents = try s.testString(alloc, .screen);
+        defer alloc.free(contents);
+        try testing.expectEqualStrings("4ABCD\n5EFGH\n6IJKL", contents);
+    }
+}
+
 test "Screen: selectionString" {
     const testing = std.testing;
     const alloc = testing.allocator;

src/terminal/Terminal.zig

@@ -806,11 +806,7 @@ pub fn eraseDisplay(
             self.screen.cursor.pending_wrap = false;
         },
 
-        .scrollback => {
-            var it = self.screen.rowIterator(.history);
-            while (it.next()) |row| row.clear(self.screen.cursor.pen);
-            @panic("MOVE TO SCREEN SO CIRC BUF IS CORRECT");
-        },
+        .scrollback => self.screen.clearHistory(),
     }
 }