parse_util: Only reject time in a pipeline without decorator

This allows e.g. `foo | command time`, while still rejecting `foo | time`.

(this should really be done in the ast itself, but tbh most of
parse_util kinda should)

Fixes #9985

(cherry picked from commit 482616f101)

src/parse_util.cpp

@@ -1165,8 +1165,16 @@ static bool detect_errors_in_decorated_statement(const wcstring &buff_src,
 
         // Similarly for time (#8841).
         if (command == L"time") {
-            errored = append_syntax_error(parse_errors, source_start, source_length,
-                                          TIME_IN_PIPELINE_ERR_MSG);
+            // We only reject it if we have no decoration.
+            // `echo foo | command time something`
+            // is entirely fair and valid.
+            // Other current decorations like "exec"
+            // are already forbidden.
+            const auto &deco = dst.decoration();
+            if (deco == statement_decoration_t::none) {
+                errored = append_syntax_error(parse_errors, source_start, source_length,
+                                              TIME_IN_PIPELINE_ERR_MSG);
+            }
         }
     }
 

tests/checks/time.fish

@@ -48,3 +48,17 @@ $fish -c 'not time true&'
 #CHECKERR: not time true&
 #FIXME: This error marks the entire statement. Would be cool to mark just `time true&`.
 #CHECKERR: ^~~~~~~~~~~~~^
+
+$fish -c 'echo Is it time yet | time cat'
+#CHECKERR: fish: The 'time' command may only be at the beginning of a pipeline
+#CHECKERR: echo Is it time yet | time cat
+#CHECKERR:                       ^~~~~~~^
+
+begin
+    printf '%s\n' "#!/bin/sh" 'echo No this is Patrick' > time
+    chmod +x time
+    set -l PATH .
+    echo Hello is this time | command time
+    # CHECK: No this is Patrick
+end
+rm time