bell doesn't crash

TODO.md

@@ -7,3 +7,7 @@ Performance:
 Correctness:
 
 * `exit` in the shell should close the window
+
+Visual:
+
+* bell

src/terminal/Terminal.zig

@@ -4,11 +4,14 @@
 const Terminal = @This();
 
 const std = @import("std");
+const builtin = @import("builtin");
 const testing = std.testing;
 const Allocator = std.mem.Allocator;
 const ansi = @import("ansi.zig");
 const Parser = @import("Parser.zig");
 
+const log = std.log.scoped(.terminal);
+
 /// Screen is the current screen state.
 screen: Screen,
 
@@ -105,6 +108,7 @@ pub fn append(self: *Terminal, alloc: Allocator, str: []const u8) !void {
 ///
 /// This may allocate if necessary to store the character in the grid.
 pub fn appendChar(self: *Terminal, alloc: Allocator, c: u8) !void {
+    log.debug("char: {}", .{c});
     const actions = self.parser.next(c);
     for (actions) |action_opt| {
         switch (action_opt orelse continue) {
@@ -127,12 +131,19 @@ fn print(self: *Terminal, alloc: Allocator, c: u8) !void {
 
 fn execute(self: *Terminal, c: u8) !void {
     switch (@intToEnum(ansi.C0, c)) {
+        .BEL => self.bell(),
         .BS => self.backspace(),
         .LF => self.linefeed(),
         .CR => self.carriage_return(),
     }
 }
 
+pub fn bell(self: *Terminal) void {
+    // TODO: bell
+    _ = self;
+    log.info("bell", .{});
+}
+
 /// Backspace moves the cursor back a column (but not less than 0).
 pub fn backspace(self: *Terminal) void {
     self.cursor.x -|= 1;

src/terminal/ansi.zig

@@ -3,6 +3,8 @@
 /// This is not complete, control characters are only added to this
 /// as the terminal emulator handles them.
 pub const C0 = enum(u7) {
+    /// Bell
+    BEL = 0x07,
     /// Backspace
     BS = 0x08,
     /// Line feed