From 0e9d159bc2e95d71ae2051957397bc689e020e42 Mon Sep 17 00:00:00 2001
From: ridiculousfish <corydoras@ridiculousfish.com>
Date: Wed, 8 Jan 2014 18:20:55 -0800
Subject: [PATCH] Improvements to error reporting. In particular, we now append
 a newline in reader_shell_test, so that there's always a statement
 terminator. Otherwise commands like 'echo |' would not be considered an error
 (just incomplete).

---
 parse_execution.cpp | 34 ++++++++++++++++++++--------------
 reader.cpp          | 15 ++++++++++-----
 2 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/parse_execution.cpp b/parse_execution.cpp
index c628b1d63..518ff479a 100644
--- a/parse_execution.cpp
+++ b/parse_execution.cpp
@@ -638,20 +638,26 @@ parse_execution_result_t parse_execution_context_t::run_while_statement(const pa
 /* Reports an error. Always returns parse_execution_errored, so you can assign the result to an 'errored' variable */
 parse_execution_result_t parse_execution_context_t::report_error(const parse_node_t &node, const wchar_t *fmt, ...)
 {
-    parse_error_t error;
-    error.source_start = node.source_start;
-    error.source_length = node.source_length;
-    error.code = parse_error_syntax; //hackish
-    
-    va_list va;
-    va_start(va, fmt);
-    error.text = vformat_string(fmt, va);
-    va_end(va);
-    
-    /* Get a backtrace */
-    wcstring backtrace;
-    const parse_error_list_t error_list = parse_error_list_t(1, error);
-    parser->get_backtrace(src, error_list, &backtrace);
+    if (parser->show_errors)
+    {
+        /* Create an error */
+        parse_error_t error;
+        error.source_start = node.source_start;
+        error.source_length = node.source_length;
+        error.code = parse_error_syntax; //hackish
+        
+        va_list va;
+        va_start(va, fmt);
+        error.text = vformat_string(fmt, va);
+        va_end(va);
+        
+        /* Get a backtrace */
+        wcstring backtrace_and_desc;
+        const parse_error_list_t error_list = parse_error_list_t(1, error);
+        parser->get_backtrace(src, error_list, &backtrace_and_desc);
+        
+        fprintf(stderr, "%ls", backtrace_and_desc.c_str());
+    }
     
     return parse_execution_errored;
 }
diff --git a/reader.cpp b/reader.cpp
index b03b84a80..c5857f900 100644
--- a/reader.cpp
+++ b/reader.cpp
@@ -2470,21 +2470,26 @@ void reader_run_command(parser_t &parser, const wcstring &cmd)
 
 int reader_shell_test(const wchar_t *b)
 {
+    assert(b != NULL);
     wcstring bstr = b;
+    
+    /* Append a newline, to act as a statement terminator */
+    bstr.push_back(L'\n');
+    
     parse_error_list_t errors;
     int res = parse_util_detect_errors(bstr, &errors);
 
     if (res & PARSER_TEST_ERROR)
     {
-        wcstring sb;
-        parser_t::principal_parser().get_backtrace(bstr, errors, &sb);
+        wcstring error_desc;
+        parser_t::principal_parser().get_backtrace(bstr, errors, &error_desc);
         
         // ensure we end with a newline. Also add an initial newline, because it's likely the user just hit enter and so there's junk on the current line
-        if (! string_suffixes_string(L"\n", sb))
+        if (! string_suffixes_string(L"\n", error_desc))
         {
-            sb.push_back(L'\n');
+            error_desc.push_back(L'\n');
         }
-        fwprintf(stderr, L"\n%ls", sb.c_str());
+        fwprintf(stderr, L"\n%ls", error_desc.c_str());
     }
     return res;
 }