silence library std.log: ghostty-vt's unimplemented-sequence chatter was painting over the UI

2 files changed, 30 insertions, 9 deletions

diff --git a/src/dump.zig b/src/dump.zig
index 06b9cec6..51221197 100644
--- a/src/dump.zig
+++ b/src/dump.zig
@@ -1,6 +1,11 @@
 const std = @import("std");
 const builtin = @import("builtin");
 
+// scoped, not bare std.log: main.zig's logFn drops the unscoped .default scope
+// wholesale (ghostty and uucode log there too), and a corrupt dump's parse
+// diagnostic is the only thing that says WHICH field went bad.
+const log = std.log.scoped(.dump);
+
 /// Where the next dump goes. $PARDES_DUMP wins verbatim (the snapshot harness
 /// pins it for deterministic goldens); else $XDG_DATA_HOME|~/.local/share
 /// /pardes/pardes-<utc>.zon — timestamped so dumps never overwrite each other.
@@ -148,7 +153,7 @@ pub fn readZon(gpa: std.mem.Allocator, bytes: []const u8, label: []const u8) !St
 pub fn readZonZ(gpa: std.mem.Allocator, source: [:0]const u8, label: []const u8) !State {
     if (builtin.os.tag == .emscripten) {
         const state = std.zon.parse.fromSliceAlloc(State, gpa, source, null, .{}) catch |err| {
-            std.log.err("parse dump {s}: {s}", .{ label, @errorName(err) });
+            log.err("parse dump {s}: {s}", .{ label, @errorName(err) });
             return err;
         };
         errdefer std.zon.parse.free(gpa, state);
@@ -159,7 +164,7 @@ pub fn readZonZ(gpa: std.mem.Allocator, source: [:0]const u8, label: []const u8)
     var diag: std.zon.parse.Diagnostics = .{};
     defer diag.deinit(gpa);
     const state = std.zon.parse.fromSliceAlloc(State, gpa, source, &diag, .{}) catch |err| {
-        std.log.err("parse dump {s}: {f}", .{ label, diag });
+        log.err("parse dump {s}: {f}", .{ label, diag });
         return err;
     };
     errdefer std.zon.parse.free(gpa, state);
diff --git a/src/main.zig b/src/main.zig
index 47121691..61c0049e 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -18,13 +18,29 @@ pub const std_options_debug_io: std.Io = if (is_emscripten)
 else
     std_options_debug_threaded_io.?.io();
 
-// ghostty-vt's stream logs every mode it doesn't implement, and in the tty
-// shell stderr IS the screen — the warning scribbles over the grid. macOS
-// bash/readline sends one such mode (1034, meta-key) on every startup, so
-// keep the stream scope to errors; linux shells just never tripped it.
-pub const std_options: std.Options = .{
-    .log_scope_levels = &.{.{ .scope = .stream, .level = .err }},
-};
+// Every std.log call in the process — ours and every dependency's — funnels
+// through this one function. ghostty-vt narrates whatever it does not
+// implement in the bytes a child writes to its pty (`debug(stream)`,
+// `warning(stream): ignoring unimplemented CSI p`, `debug(kitty_gfx)`; opening
+// yazi is worth several lines before it has drawn anything), and in the tty
+// shell stderr IS the screen — those land on top of the rendered grid, and in
+// the gui/web shells on the console. So drop the libraries at every level: an
+// `err` painted over the UI is no better than a debug one. Only pardes' own
+// scopes get through, because their messages carry detail the error returns
+// don't (gui's SDL_GetError strings, dump's zon parse diagnostic) — .default
+// is NOT one of them, ghostty and uucode both log unscoped. Set PARDES_LOG to
+// get the real logger back: `PARDES_LOG=1 pardes 2>/tmp/pardes.log`.
+pub const std_options: std.Options = .{ .logFn = logFn };
+
+fn logFn(
+    comptime level: std.log.Level,
+    comptime scope: @EnumLiteral(),
+    comptime format: []const u8,
+    args: anytype,
+) void {
+    if (scope != .gui and scope != .dump and std.c.getenv("PARDES_LOG") == null) return;
+    std.log.defaultLog(level, scope, format, args);
+}
 
 // A panic must restore the terminal (cooked mode, main screen, mouse off)
 // before the trace prints, or it lands garbled in a raw alt screen. recover()