A look at a corrupt image fails with an err rather than open a blank pane

An image stb_image could not read opened as an empty image pane, the look succeeding. The bytes' header is now checked at the look (stbi_info_from_memory), and one that is no image it reads fails the look, look: <path>: not an image pardes can read, making no pane.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 10 insertions, 1 deletions

diff --git a/src/look.zig b/src/look.zig
index 6f279769..5cf26240 100644
--- a/src/look.zig
+++ b/src/look.zig
@@ -1572,8 +1572,17 @@ pub fn lookAt(p: *Pardes, id: usize, operand: []const u8) void {
         .image => |target| {
             if (focusPaneByPath(p, target.path, .{})) return;
             const free = p.freeSlot() orelse return p.reportError(id, "look", error.NoPaneSlots);
-            _ = panes.Image.create(p, free, target.path, &.{}) catch |err|
+            const made = panes.Image.create(p, free, target.path, &.{}) catch |err|
                 return p.reportError(id, if (@import("Messages.zig").dialReason(err) != null) target.path else "look", err);
+            // One it cannot read (corrupt, truncated, not what its name says)
+            // is said, a failure, rather than shown as a blank pane.
+            if (!@import("image.zig").readable(made.image.?.raw)) {
+                made.vweight = 0;
+                p.unplaced.set(free);
+                var said: [miss_path_cap + 64]u8 = undefined;
+                var cut: [miss_path_cap + "…".len]u8 = undefined;
+                return p.reportFailure(id, std.fmt.bufPrint(&said, "look: {s}: not an image pardes can read", .{missText(target.path, &cut)}) catch "look: not an image pardes can read");
+            }
             exec.placeNew(p, id, id, free, .doc);
         },
     }