Lspwhy explains the last language server query asked, its kind, argument and place, not always a definition at the cursor

Lspwhy said it explains how the last request was answered, but it always
replayed a definition query at the current cursor. So after a failed Hover
it narrated a gd somewhere else, which told nothing about the failure.
Now the core remembers the last query (kind, argument, pane, offset), and
Lspwhy sends it as `<kind> <arg>`, at the query's offset when asked from
the same pane. The client narrates that kind: lsp.explaining reads it, and
the heading names it ("the hover query at byte N"). With nothing asked yet
it is a definition, as before. The effect's arg grows to 160 bytes so a
128-byte argument fits with its kind.

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

1 files changed, 8 insertions, 6 deletions

diff --git a/src/lsp/lsp_client.zig b/src/lsp/lsp_client.zig
index 7704d0ad..0c5e3b7e 100644
--- a/src/lsp/lsp_client.zig
+++ b/src/lsp/lsp_client.zig
@@ -405,8 +405,9 @@ const Trace = struct {
 
 // ------------------------------------------------------------------- query
 
-pub fn query(gpa: std.mem.Allocator, arena: std.mem.Allocator, req: lsp.Req, out: *std.Io.Writer) !void {
+pub fn query(gpa: std.mem.Allocator, arena: std.mem.Allocator, asked: lsp.Req, out: *std.Io.Writer) !void {
     _ = gpa;
+    const req = lsp.explaining(asked);
     if (req.kind == .status) return status(req, out);
 
     var tr: Trace = .{ .on = req.kind == .explain };
@@ -443,8 +444,8 @@ pub fn query(gpa: std.mem.Allocator, arena: std.mem.Allocator, req: lsp.Req, out
 
 fn traceOut(tr: *const Trace, req: lsp.Req, out: *std.Io.Writer, rows: usize, us: u64) std.Io.Writer.Error!void {
     if (req.kind != .explain) return;
-    try out.print("lsp explain — the definition query at byte {d} of {s}\n\n", .{
-        req.offset, if (req.path.len == 0) "(no file)" else std.fs.path.basename(req.path),
+    try out.print("lsp explain — the {s} query at byte {d} of {s}\n\n", .{
+        @tagName(req.explains), req.offset, if (req.path.len == 0) "(no file)" else std.fs.path.basename(req.path),
     });
     try out.writeAll(tr.buf[0..tr.len]);
     if (hideTime())
@@ -488,9 +489,10 @@ fn answer(arena: std.mem.Allocator, si: usize, req: lsp.Req, out: *std.Io.Writer
 }
 
 fn run(c: *Conn, si: usize, arena: std.mem.Allocator, req: lsp.Req, out: *std.Io.Writer, tr: *Trace) Err!void {
-    // `explain` narrates the definition query — dispatch below on the
-    // effective kind so the trace follows the code `gd` really runs.
-    const kind: lsp.Kind = if (req.kind == .explain) .definition else req.kind;
+    // `explain` narrates the last query asked (a definition, `gd`, when
+    // none was) — dispatch below on the effective kind so the trace
+    // follows the code that query really runs.
+    const kind: lsp.Kind = if (req.kind == .explain) req.explains else req.kind;
 
     // Both arg-taking kinds are useless without one, and an empty
     // workspace/symbol query means "every symbol in the project".