Fix error messages for "and" and "or" after pipe

Fixes #6347

src/parse_constants.h

@@ -178,6 +178,7 @@ enum parse_error_code_t {
     parse_error_unbalancing_else,          // else outside of if
     parse_error_unbalancing_case,          // case outside of switch
     parse_error_bare_variable_assignment,  // a=b without command
+    parse_error_andor_in_pipeline,         // "and" or "or" after a pipe
 };
 
 enum { PARSER_TEST_ERROR = 1, PARSER_TEST_INCOMPLETE = 2 };

src/parse_tree.cpp

@@ -53,14 +53,23 @@ wcstring parse_error_t::describe_with_prefix(const wcstring &src, const wcstring
     if (skip_caret && this->text.empty()) return L"";
 
     wcstring result = prefix;
-    if (code == parse_error_bare_variable_assignment) {
-        wcstring assignment_src = src.substr(this->source_start, this->source_length);
-        maybe_t<size_t> equals_pos = variable_assignment_equals_pos(assignment_src);
-        assert(equals_pos);
-        wcstring variable = assignment_src.substr(0, *equals_pos);
-        wcstring value = assignment_src.substr(*equals_pos + 1);
-        append_format(result, ERROR_BAD_COMMAND_ASSIGN_ERR_MSG, variable.c_str(), value.c_str());
-        return result;
+    switch (code) {
+        default:
+            break;
+        case parse_error_andor_in_pipeline:
+            append_format(result, EXEC_ERR_MSG,
+                          src.substr(this->source_start, this->source_length).c_str());
+            return result;
+        case parse_error_bare_variable_assignment: {
+            wcstring assignment_src = src.substr(this->source_start, this->source_length);
+            maybe_t<size_t> equals_pos = variable_assignment_equals_pos(assignment_src);
+            assert(equals_pos);
+            wcstring variable = assignment_src.substr(0, *equals_pos);
+            wcstring value = assignment_src.substr(*equals_pos + 1);
+            append_format(result, ERROR_BAD_COMMAND_ASSIGN_ERR_MSG, variable.c_str(),
+                          value.c_str());
+            return result;
+        }
     }
     result.append(this->text);
     if (skip_caret || source_start >= src.size() || source_start + source_length > src.size()) {
@@ -929,6 +938,17 @@ void parse_ll_t::accept_tokens(parse_token_t token1, parse_token_t token2) {
         if (production == nullptr) {
             tnode_t<grammar::variable_assignments> variable_assignments;
             if (const parse_node_t *parent = nodes.get_parent(node)) {
+                if (parent->type == symbol_statement &&
+                    (token1.keyword == parse_keyword_and || token1.keyword == parse_keyword_or)) {
+                    if (const parse_node_t *grandparent = nodes.get_parent(*parent)) {
+                        if (grandparent->type == symbol_job_continuation) {
+                            parse_error(token1, parse_error_andor_in_pipeline, L" "
+                                /* won't be printed but must be non-empty, see
+                                    describe_with_prefix TODO clean that up */);
+                            continue;
+                        }
+                    }
+                }
                 switch (parent->type) {
                     default:
                         break;

src/parse_tree.h

@@ -238,4 +238,7 @@ parsed_source_ref_t parse_source(wcstring src, parse_tree_flags_t flags, parse_e
 /// The position of the equal sign in a variable assignment like foo=bar.
 maybe_t<size_t> variable_assignment_equals_pos(const wcstring &txt);
 
+/// Error message for improper use of the exec builtin.
+#define EXEC_ERR_MSG _(L"The '%ls' command can not be used in a pipeline")
+
 #endif

src/parse_util.cpp

@@ -28,9 +28,6 @@
 #include "wildcard.h"
 #include "wutil.h"  // IWYU pragma: keep
 
-/// Error message for improper use of the exec builtin.
-#define EXEC_ERR_MSG _(L"The '%ls' command can not be used in a pipeline")
-
 /// Error message for use of backgrounded commands before and/or.
 #define BOOL_AFTER_BACKGROUND_ERROR_MSG \
     _(L"The '%ls' command can not be used immediately after a backgrounded job")

tests/checks/andor.fish

@@ -0,0 +1,9 @@
+#RUN: %fish %s
+
+set -xl LANG C # uniform quotes
+
+eval 'true | and'
+# CHECKERR: {{.*}}: The 'and' command can not be used in a pipeline
+
+eval 'true | or'
+# CHECKERR: {{.*}}: The 'or' command can not be used in a pipeline