Replace \e with \x1B, as the former is a gcc extension

While supported by gcc and clang, \e is a gcc-specific extension and not
formally defined in the C or C++ standards.

See [0] for a list of valid escapes.

[0]: https://stackoverflow.com/a/10220539/17027

src/builtin_echo.cpp

@@ -214,7 +214,7 @@ int builtin_echo(parser_t &parser, io_streams_t &streams, wchar_t **argv) {
                         break;
                     }
                     case L'e': {
-                        wc = L'\e';
+                        wc = L'\x1B';
                         break;
                     }
                     case L'f': {

src/builtin_printf.cpp

@@ -26,7 +26,7 @@
 // \a = alert (bell)
 // \b = backspace
 // \c = produce no further output
-// \e = escape
+// \x1B = escape
 // \f = form feed
 // \n = new line
 // \r = carriage return
@@ -317,7 +317,7 @@ void builtin_printf_state_t::print_esc_char(wchar_t c) {
             break;
         }
         case L'e': {  // escape
-            this->append_output(L'\e');
+            this->append_output(L'\x1B');
             break;
         }
         case L'f': {  // form feed

src/builtin_set_color.cpp

@@ -62,9 +62,9 @@ static const struct woption long_options[] = {{L"background", required_argument,
                                               {NULL, 0, NULL, 0}};
 
 #if __APPLE__
-char sitm_esc[] = "\e[3m";
+char sitm_esc[] = "\x1B[3m";
-char ritm_esc[] = "\e[23m";
+char ritm_esc[] = "\x1B[23m";
-char dim_esc[] = "\e[2m";
+char dim_esc[] = "\x1B[2m";
 #endif
 
 /// set_color builtin.

src/common.cpp

@@ -981,7 +981,7 @@ static void escape_string_script(const wchar_t *orig_in, size_t in_len, wcstring
                     need_escape = need_complex_escape = 1;
                     break;
                 }
-                case L'\e': {
+                case L'\x1B': {
                     out += L'\\';
                     out += L'e';
                     need_escape = need_complex_escape = 1;
@@ -1243,9 +1243,9 @@ size_t read_unquoted_escape(const wchar_t *input, wcstring *result, bool allow_i
             }
             break;
         }
-        // \e means escape.
+        // \x1B means escape.
         case L'e': {
-            result_char_or_none = L'\e';
+            result_char_or_none = L'\x1B';
             break;
         }
         // \f means form feed.

src/expand.cpp

@@ -132,7 +132,7 @@ static int is_quotable(const wchar_t *str) {
         case L'\t':
         case L'\r':
         case L'\b':
-        case L'\e': {
+        case L'\x1B': {
             return 0;
         }
         default: { return is_quotable(str + 1); }

src/fish_key_reader.cpp

@@ -40,7 +40,7 @@ struct config_paths_t determine_config_directory_paths(const char *argv0);
 static const wchar_t *ctrl_symbolic_names[] = {
     NULL,   NULL,   NULL,   NULL, NULL, NULL,   NULL, L"\\a", L"\\b", L"\\t", L"\\n",
     L"\\v", L"\\f", L"\\r", NULL, NULL, NULL,   NULL, NULL,   NULL,   NULL,   NULL,
-    NULL,   NULL,   NULL,   NULL, NULL, L"\\e", NULL, NULL,   NULL,   NULL};
+    NULL,   NULL,   NULL,   NULL, NULL, L"\\x1B", NULL, NULL,   NULL,   NULL};
 static bool keep_running = true;
 
 /// Return true if the recent sequence of characters indicates the user wants to exit the program.

src/fish_tests.cpp

@@ -125,7 +125,7 @@ static void err(const wchar_t *blah, ...) {
 
     // Show errors in red.
     if (colorize) {
-        fputws(L"\e[31m", stdout);
+        fputws(L"\x1B[31m", stdout);
     }
     fwprintf(stdout, L"Error: ");
     vfwprintf(stdout, blah, va);
@@ -133,7 +133,7 @@ static void err(const wchar_t *blah, ...) {
 
     // Return to normal color.
     if (colorize) {
-        fputws(L"\e[0m", stdout);
+        fputws(L"\x1B[0m", stdout);
     }
 
     fwprintf(stdout, L"\n");
@@ -1398,25 +1398,25 @@ static void test_escape_sequences() {
     if (escape_code_length(L"") != 0) err(L"test_escape_sequences failed on line %d\n", __LINE__);
     if (escape_code_length(L"abcd") != 0)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e[2J") != 4)
+    if (escape_code_length(L"\x1B[2J") != 4)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e[38;5;123mABC") != strlen("\e[38;5;123m"))
+    if (escape_code_length(L"\x1B[38;5;123mABC") != strlen("\x1B[38;5;123m"))
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e@") != 2)
+    if (escape_code_length(L"\x1B@") != 2)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
 
     // iTerm2 escape sequences.
-    if (escape_code_length(L"\e]50;CurrentDir=test/foo\x07NOT_PART_OF_SEQUENCE") != 25)
+    if (escape_code_length(L"\x1B]50;CurrentDir=test/foo\x07NOT_PART_OF_SEQUENCE") != 25)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e]50;SetMark\x07NOT_PART_OF_SEQUENCE") != 13)
+    if (escape_code_length(L"\x1B]50;SetMark\x07NOT_PART_OF_SEQUENCE") != 13)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e]6;1;bg;red;brightness;255\x07NOT_PART_OF_SEQUENCE") != 28)
+    if (escape_code_length(L"\x1B]6;1;bg;red;brightness;255\x07NOT_PART_OF_SEQUENCE") != 28)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e]Pg4040ff\e\\NOT_PART_OF_SEQUENCE") != 12)
+    if (escape_code_length(L"\x1B]Pg4040ff\x1B\\NOT_PART_OF_SEQUENCE") != 12)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e]blahblahblah\e\\") != 16)
+    if (escape_code_length(L"\x1B]blahblahblah\x1B\\") != 16)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
-    if (escape_code_length(L"\e]blahblahblah\x07") != 15)
+    if (escape_code_length(L"\x1B]blahblahblah\x07") != 15)
         err(L"test_escape_sequences failed on line %d\n", __LINE__);
 }
 

src/input.cpp

@@ -265,10 +265,10 @@ void init_input() {
         input_mapping_add(L"\x5", L"bind");
         input_mapping_add(L"\x7f", L"backward-delete-char");
         // Arrows - can't have functions, so *-or-search isn't available.
-        input_mapping_add(L"\e[A", L"up-line");
+        input_mapping_add(L"\x1B[A", L"up-line");
-        input_mapping_add(L"\e[B", L"down-line");
+        input_mapping_add(L"\x1B[B", L"down-line");
-        input_mapping_add(L"\e[C", L"forward-char");
+        input_mapping_add(L"\x1B[C", L"forward-char");
-        input_mapping_add(L"\e[D", L"backward-char");
+        input_mapping_add(L"\x1B[D", L"backward-char");
     }
 
     input_initialized = true;
@@ -392,7 +392,7 @@ static bool input_mapping_is_match(const input_mapping_t &m) {
 
         // If we just read an escape, we need to add a timeout for the next char,
         // to distinguish between the actual escape key and an "alt"-modifier.
-        timed = (str[i] == L'\e');
+        timed = (str[i] == L'\x1B');
     }
 
     return true;

src/input_common.cpp

@@ -29,7 +29,7 @@
 #include "wutil.h"
 
 /// Time in milliseconds to wait for another byte to be available for reading
-/// after \e is read before assuming that escape key was pressed, and not an
+/// after \x1B is read before assuming that escape key was pressed, and not an
 /// escape sequence.
 #define WAIT_ON_ESCAPE_DEFAULT 300
 static int wait_on_escape_ms = WAIT_ON_ESCAPE_DEFAULT;

src/output.cpp

@@ -80,9 +80,9 @@ static bool write_color_escape(char *todo, unsigned char idx, bool is_fg) {
         // with what we do here, will make the brights actually work for virtual consoles/ancient
         // emulators.
         if (max_colors == 8 && idx > 8) idx -= 8;
-        snprintf(buff, sizeof buff, "\e[%dm", ((idx > 7) ? 82 : 30) + idx + !is_fg * 10);
+        snprintf(buff, sizeof buff, "\x1B[%dm", ((idx > 7) ? 82 : 30) + idx + !is_fg * 10);
     } else {
-        snprintf(buff, sizeof buff, "\e[%d;5;%dm", is_fg ? 38 : 48, idx);
+        snprintf(buff, sizeof buff, "\x1B[%d;5;%dm", is_fg ? 38 : 48, idx);
     }
 
     int (*writer)(char) = output_get_writer();
@@ -131,7 +131,7 @@ bool write_color(rgb_color_t color, bool is_fg) {
     // Background: ^[48;2;<r>;<g>;<b>m
     color24_t rgb = color.to_color24();
     char buff[128];
-    snprintf(buff, sizeof buff, "\e[%d;2;%u;%u;%um", is_fg ? 38 : 48, rgb.rgb[0], rgb.rgb[1],
+    snprintf(buff, sizeof buff, "\x1B[%d;2;%u;%u;%um", is_fg ? 38 : 48, rgb.rgb[0], rgb.rgb[1],
              rgb.rgb[2]);
     int (*writer)(char) = output_get_writer();
     if (writer) {

src/proc.cpp

@@ -476,7 +476,7 @@ static void format_job_info(const job_t *j, job_status_t status) {
     if (cur_term) {
         tputs(clr_eol, 1, &writeb);
     } else {
-        fwprintf(stdout, L"\e[K");
+        fwprintf(stdout, L"\x1B[K");
     }
     fwprintf(stdout, L"\n");
 }
@@ -582,7 +582,7 @@ static int process_clean_after_marking(bool allow_interactive) {
                 if (cur_term != NULL) {
                     tputs(clr_eol, 1, &writeb);
                 } else {
-                    fwprintf(stdout, L"\e[K");  // no term set up - do clr_eol manually
+                    fwprintf(stdout, L"\x1B[K");  // no term set up - do clr_eol manually
                 }
                 fwprintf(stdout, L"\n");
             }

src/reader.cpp

@@ -687,7 +687,7 @@ void reader_write_title(const wcstring &cmd, bool reset_cursor_position) {
     proc_push_interactive(0);
     if (exec_subshell(fish_title_command, lst, false /* ignore exit status */) != -1 &&
         !lst.empty()) {
-        fputws(L"\e]0;", stdout);
+        fputws(L"\x1B]0;", stdout);
         for (size_t i = 0; i < lst.size(); i++) {
             fputws(lst.at(i).c_str(), stdout);
         }
@@ -2687,7 +2687,7 @@ const wchar_t *reader_readline(int nchars) {
                 break;
             }
             // Escape was pressed.
-            case L'\e': {
+            case L'\x1B': {
                 if (data->search_mode != history_search_mode_t::none) {
                     data->search_mode = history_search_mode_t::none;
 

src/screen.cpp

@@ -125,7 +125,7 @@ static bool is_screen_name_escape_seq(const wchar_t *code, size_t *resulting_len
     }
 #endif
 
-    const wchar_t *const screen_name_end_sentinel = L"\e\\";
+    const wchar_t *const screen_name_end_sentinel = L"\x1B\\";
     const wchar_t *screen_name_end = wcsstr(&code[2], screen_name_end_sentinel);
     if (screen_name_end == NULL) {
         // Consider just <esc>k to be the code.
@@ -146,7 +146,7 @@ static bool is_iterm2_escape_seq(const wchar_t *code, size_t *resulting_length)
         size_t cursor = 2;
         for (; code[cursor] != L'\0'; cursor++) {
             // Consume a sequence of characters up to <esc>\ or <bel>.
-            if (code[cursor] == '\x07' || (code[cursor] == '\\' && code[cursor - 1] == '\e')) {
+            if (code[cursor] == '\x07' || (code[cursor] == '\\' && code[cursor - 1] == '\x1B')) {
                 found = true;
                 break;
             }
@@ -261,11 +261,11 @@ static bool is_visual_escape_seq(const wchar_t *code, size_t *resulting_length)
 }
 
 /// Returns the number of characters in the escape code starting at 'code'. We only handle sequences
-/// that begin with \e. If it doesn't we return zero. We also return zero if we don't recognize the
+/// that begin with \x1B. If it doesn't we return zero. We also return zero if we don't recognize the
 /// escape sequence based on querying terminfo and other heuristics.
 size_t escape_code_length(const wchar_t *code) {
     assert(code != NULL);
-    if (*code != L'\e') return 0;
+    if (*code != L'\x1B') return 0;
 
     size_t esc_seq_len = cached_layouts.find_escape_code(code);
     if (esc_seq_len) return esc_seq_len;
@@ -313,7 +313,7 @@ static prompt_layout_t calc_prompt_layout(const wcstring &prompt, layout_cache_t
     size_t current_line_width = 0;
 
     for (int j = 0; prompt[j]; j++) {
-        if (prompt[j] == L'\e') {
+        if (prompt[j] == L'\x1B') {
             // This is the start of an escape code. Skip over it if it's at least one char long.
             size_t len = escape_code_length(&prompt[j]);
             if (len > 0) j += len - 1;