simplify, and fix, setting the current locale

Fix test setup bogosities. Specifically, they weren't hermetic with respect to
locale env vars.

Rewrite the handling of locale vars to simplify the code and make it more like
the pattern most programs employ.

Fixes #3110

1 files changed, 29 insertions, 31 deletions

diff --git a/src/env.cpp b/src/env.cpp
index 71d85800..84baa76f 100644
--- a/src/env.cpp
+++ b/src/env.cpp
@@ -9,6 +9,7 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
@@ -168,37 +169,33 @@ static bool var_is_locale(const wcstring &key) {
 }
 
 /// Properly sets all locale information.
-static void handle_locale() {
-    const env_var_t lc_all = env_get_string(L"LC_ALL");
-    const wcstring old_locale = wsetlocale(LC_MESSAGES, NULL);
+static void handle_locale(const wchar_t *env_var_name) {
+    debug(2, L"handle_locale() called in response to '%ls' changing", env_var_name);
+    const char *old_msg_locale = setlocale(LC_MESSAGES, NULL);
 
-    // Array of locale constants corresponding to the local variable names defined in
-    // locale_variable.
-    static const int cat[] = {0,           LC_ALL,      LC_COLLATE, LC_CTYPE,
-                              LC_MESSAGES, LC_MONETARY, LC_NUMERIC, LC_TIME};
-
-    if (!lc_all.missing()) {
-        wsetlocale(LC_ALL, lc_all.c_str());
-    } else {
-        const env_var_t lang = env_get_string(L"LANG");
-        if (!lang.missing()) {
-            wsetlocale(LC_ALL, lang.c_str());
-        }
-
-        for (int i = 2; locale_variable[i]; i++) {
-            const env_var_t val = env_get_string(locale_variable[i]);
-
-            if (!val.missing()) {
-                wsetlocale(cat[i], val.c_str());
-            }
+    for (size_t i = 0; locale_variable[i]; i++) {
+        const wchar_t *key = locale_variable[i];
+        const env_var_t var = env_get_string(key);
+        if (!var.empty()) {
+            const std::string &name = wcs2string(key);
+            const std::string &value = wcs2string(var);
+            setenv(name.c_str(), value.c_str(), 1);
+            debug(3, L"locale var %s='%s'", name.c_str(), value.c_str());
         }
     }
 
-    const wcstring new_locale = wsetlocale(LC_MESSAGES, NULL);
-    if (old_locale != new_locale) {
+    char *locale = setlocale(LC_ALL, "");
+    fish_setlocale();
+    debug(2, L"handle_locale() setlocale(): '%s'", locale);
+
+    const char *new_msg_locale = setlocale(LC_MESSAGES, NULL);
+    debug(3, L"old LC_MESSAGES locale: '%s'", old_msg_locale);
+    debug(3, L"new LC_MESSAGES locale: '%s'", new_msg_locale);
+    if (strcmp(old_msg_locale, new_msg_locale)) {
         // Try to make change known to gettext. Both changing _nl_msg_cat_cntr and calling dcgettext
         // might potentially tell some gettext implementation that the translation strings should be
         // reloaded. We do both and hope for the best.
+        debug(2, L"changing message locale from '%s' to '%s'", old_msg_locale, new_msg_locale);
         extern int _nl_msg_cat_cntr;
         _nl_msg_cat_cntr++;
         fish_dcgettext("fish", "Changing language to English", LC_MESSAGES);
@@ -217,7 +214,8 @@ static bool var_is_curses(const wcstring &key) {
 
 /// Push all curses/terminfo env vars into the global environment where they can be found by those
 /// libraries.
-static void handle_curses() {
+static void handle_curses(const wchar_t *env_var_name) {
+    debug(2, L"handle_curses() called in response to '%ls' changing", env_var_name);
     for (size_t i = 0; curses_variable[i]; i++) {
         const wchar_t *key = curses_variable[i];
         const env_var_t var = env_get_string(key);
@@ -225,6 +223,7 @@ static void handle_curses() {
             const std::string &name = wcs2string(key);
             const std::string &value = wcs2string(var);
             setenv(name.c_str(), value.c_str(), 1);
+            debug(3, L"curses var %s='%s'", name.c_str(), value.c_str());
         }
     }
     // TODO: Modify input_init() to allow calling it when the terminfo env vars are dynamically
@@ -236,9 +235,9 @@ static void handle_curses() {
 /// React to modifying the given variable.
 static void react_to_variable_change(const wcstring &key) {
     if (var_is_locale(key)) {
-        handle_locale();
+        handle_locale(key.c_str());
     } else if (var_is_curses(key)) {
-        handle_curses();
+        handle_curses(key.c_str());
     } else if (key == L"fish_term256" || key == L"fish_term24bit") {
         update_fish_color_support();
         reader_react_to_color_change();
@@ -852,14 +851,13 @@ void env_push(bool new_scope) {
 void env_pop() {
     if (&top->env != global) {
         int i;
-        int locale_changed = 0;
-
+        const wchar_t *locale_changed = NULL;
         env_node_t *killme = top;
 
         for (i = 0; locale_variable[i]; i++) {
             var_table_t::iterator result = killme->env.find(locale_variable[i]);
             if (result != killme->env.end()) {
-                locale_changed = 1;
+                locale_changed = locale_variable[i];
                 break;
             }
         }
@@ -881,7 +879,7 @@ void env_pop() {
 
         delete killme;
 
-        if (locale_changed) handle_locale();
+        if (locale_changed) handle_locale(locale_changed);
 
     } else {
         debug(0, _(L"Tried to pop empty environment stack."));