Resolve overflows in UI drawing for buffer list view

src/controller.cpp

@@ -735,7 +735,13 @@ void Controller::add_model(const std::string& filename) {
             return lhs.filename.size() < rhs.filename.size();
         })->filename.size();
 
-    std::string title = "\u2551 id \u2502  filename " + std::string(max_name_len - 8, ' ');
+    // "filename"
+    if (max_name_len < 8) {
+        max_name_len = 8;
+    }
+    max_name_len += 2;
+
+    std::string title = "\u2551 id \u2502  filename" + std::string(uint_t(max_name_len - 8), ' ');
     title += " \u2502  pos  \u2551";
     std::size_t title_len = title.size() - 9;
 
@@ -759,21 +765,28 @@ void Controller::add_model(const std::string& filename) {
         std::string line = "\u2551  " + std::to_string(idx);
         line += " \u2502  ";
         line += rawterm::bold(m.filename);
+
+        int spacing = 0;
+        if (max_name_len > m.filename.size()) {
+            spacing = max_name_len - m.filename.size();
+        }
+
         if (m.unsaved) {
             line += rawterm::bold("*");
-            if (m.filename.size() < max_name_len) {
-                line += std::string(max_name_len - m.filename.size() - 1, ' ');
-            }
-        } else {
-            line += std::string(max_name_len - m.filename.size() + 1, ' ');
+            spacing--;
+        }
+
+        if (spacing > 0) {
+            line += std::string(spacing, ' ');
         }
 
         line += " \u2502  ";
         line += std::to_string(m.current_line + 1);
         line.push_back(':');
         line += std::to_string(m.current_char + 1);
 
-        std::size_t diff = title.size() - rawterm::raw_size(line) - std::string("\u2551").size();
+        const std::size_t diff =
+            title.size() - rawterm::raw_size(line) - std::string("\u2551").size();
         line += std::string(diff, ' ');
         line += "\u2551";
 

tests/integration/command_mode_test.py

@@ -265,18 +265,16 @@ def test_list_open_buffers(r: TmuxRunner):
     inverted_buf_name = "\x1B[7m[BUFFERS]\x1B[0m"
     assert inverted_buf_name in r.await_tab_bar_parts()
 
-    lines: list[str] = r.lines()
-    assert "0" in lines[4]
-    assert "tests/fixture/temp_file.txt" in lines[4]
-    assert "1:1" in lines[4]
-
-    assert "1" in lines[5]
-    assert "NO NAME" in lines[5]
-    assert "1:1" in lines[5]
+    expected_lines: list[str] = [
+        "║  0 │  tests/fixture/temp_file.txt     │  1:1  ║",
+        "║  1 │  NO NAME                         │  1:1  ║",
+        "║  2 │  tests/fixture/test_file_1.txt   │  1:1  ║",
+    ]
 
-    assert "2" in lines[6]
-    assert r.filename in lines[6]
-    assert "1:1" in lines[6]
+    lines: list[str] = r.lines()
+    assert expected_lines[0] in lines[4]
+    assert expected_lines[1] in lines[5]
+    assert expected_lines[2] in lines[6]
 
     assert r.await_statusbar_parts()[1] == "[RO]"