Eliminate env_snapshot_t::current()

These uses are better served by passing in the real environment stack,
now that we have environment_t as a shared base class.

src/builtin_command.cpp

@@ -10,6 +10,7 @@
 #include "common.h"
 #include "fallback.h"  // IWYU pragma: keep
 #include "io.h"
+#include "parser.h"
 #include "path.h"
 #include "wgetopt.h"
 #include "wutil.h"  // IWYU pragma: keep
@@ -102,7 +103,7 @@ int builtin_command(parser_t &parser, io_streams_t &streams, wchar_t **argv) {
             }
         } else {
             wcstring path;
-            if (path_get_path(command_name, &path)) {
+            if (path_get_path(command_name, &path, parser.vars())) {
                 if (!opts.quiet) streams.out.append_format(L"%ls\n", path.c_str());
                 ++found;
             }

src/builtin_read.cpp

@@ -455,7 +455,6 @@ int builtin_read(parser_t &parser, io_streams_t &streams, wchar_t **argv) {
     auto clear_remaining_vars = [&] () {
         while (vars_left()) {
             parser.vars().set_empty(*var_ptr, opts.place);
-            // env_set_one(*var_ptr, opts.place, L"");
             ++var_ptr;
         }
     };

src/complete.cpp

@@ -495,18 +495,19 @@ void complete_remove_all(const wcstring &cmd, bool cmd_is_path) {
 }
 
 /// Find the full path and commandname from a command string 'str'.
-static void parse_cmd_string(const wcstring &str, wcstring &path, wcstring &cmd) {
+static void parse_cmd_string(const wcstring &str, wcstring *path, wcstring *cmd,
-    if (!path_get_path(str, &path)) {
+                             const environment_t &vars) {
+    if (!path_get_path(str, path, vars)) {
         /// Use the empty string as the 'path' for commands that can not be found.
-        path = L"";
+        *path = L"";
     }
 
     // Make sure the path is not included in the command.
     size_t last_slash = str.find_last_of(L'/');
     if (last_slash != wcstring::npos) {
-        cmd = str.substr(last_slash + 1);
+        *cmd = str.substr(last_slash + 1);
     } else {
-        cmd = str;
+        *cmd = str;
     }
 }
 
@@ -865,7 +866,7 @@ bool completer_t::complete_param(const wcstring &cmd_orig, const wcstring &popt,
     bool use_common = 1, use_files = 1;
 
     wcstring cmd, path;
-    parse_cmd_string(cmd_orig, path, cmd);
+    parse_cmd_string(cmd_orig, &path, &cmd, vars);
 
     // mqudsi: run_on_main_thread() already just runs `func` if we're on the main thread,
     // but it makes a kcall to get the current thread id to ascertain that. Perhaps even
@@ -891,8 +892,8 @@ bool completer_t::complete_param(const wcstring &cmd_orig, const wcstring &popt,
         // may be faster, path_get_path can potentially do a lot of FS/IO access, so env.get() +
         // function_exists() should still be faster.
         head_exists =
-            head_exists ||
+            head_exists || path_get_path(cmd_orig, nullptr,
-            path_get_path(cmd_orig, nullptr);  // use cmd_orig here as it is potentially pathed
+                                         vars);  // use cmd_orig here as it is potentially pathed
     }
 
     if (!head_exists) {

src/env.cpp

@@ -1658,19 +1658,7 @@ env_vars_snapshot_t::env_vars_snapshot_t(const environment_t &source, const wcha
 
 env_vars_snapshot_t::~env_vars_snapshot_t() = default;
 
-// The "current" variables are not a snapshot at all, but instead trampoline to env_get, etc.
-// We identify the current snapshot based on pointer values.
-// This is an ugly thing that has to go away.
-const env_vars_snapshot_t env_vars_snapshot_t::s_current;
-const env_vars_snapshot_t &env_vars_snapshot_t::current() { return s_current; }
-
-bool env_vars_snapshot_t::is_current() const { return this == &s_current; }
-
 maybe_t<env_var_t> env_vars_snapshot_t::get(const wcstring &key, env_mode_flags_t mode) const {
-    // If we represent the current state, bounce to env_get.
-    if (this->is_current()) {
-        return env_get(key, mode);
-    }
     auto iter = vars.find(key);
     if (iter == vars.end()) return none();
     return iter->second;

src/env.h

@@ -255,9 +255,6 @@ class env_stack_t : public environment_t {
 class env_vars_snapshot_t : public environment_t {
     std::map<wcstring, env_var_t> vars;
     wcstring_list_t names;
-    bool is_current() const;
-
-    static const env_vars_snapshot_t s_current;
 
    public:
     env_vars_snapshot_t() = default;
@@ -270,9 +267,6 @@ class env_vars_snapshot_t : public environment_t {
 
     wcstring_list_t get_names(int flags) const override;
 
-    // Returns the fake snapshot representing the live variables array.
-    static const env_vars_snapshot_t &current();
-
     // Vars necessary for highlighting.
     static const wchar_t *const highlighting_keys[];
 

src/fish_indent.cpp

@@ -529,7 +529,7 @@ int main(int argc, char *argv[]) {
     std::vector<highlight_spec_t> colors;
     if (output_type != output_type_plain_text) {
         highlight_shell_no_io(output_wtext, colors, output_wtext.size(), NULL,
-                              env_vars_snapshot_t::current());
+                              env_stack_t::globals());
     }
 
     std::string colored_output;

src/highlight.cpp

@@ -364,7 +364,7 @@ bool autosuggest_validate_from_history(const history_item_t &item,
 
     // Not handled specially so handle it here.
     bool cmd_ok = false;
-    if (path_get_path(parsed_command, NULL)) {
+    if (path_get_path(parsed_command, NULL, vars)) {
         cmd_ok = true;
     } else if (builtin_exists(parsed_command) ||
                function_exists_no_autoload(parsed_command, vars)) {

src/parse_execution.cpp

@@ -800,7 +800,7 @@ parse_execution_result_t parse_execution_context_t::populate_plain_process(
     wcstring path_to_external_command;
     if (process_type == EXTERNAL || process_type == INTERNAL_EXEC) {
         // Determine the actual command. This may be an implicit cd.
-        bool has_command = path_get_path(cmd, &path_to_external_command);
+        bool has_command = path_get_path(cmd, &path_to_external_command, parser->vars());
 
         // If there was no command, then we care about the value of errno after checking for it, to
         // distinguish between e.g. no file vs permissions problem.

src/path.h

@@ -34,13 +34,12 @@ bool path_get_data(wcstring &path);
 /// Args:
 /// cmd - The name of the executable.
 /// output_or_NULL - If non-NULL, store the full path.
-/// vars - The environment variables snapshot to use
+/// vars - The environment variables to use
 ///
 /// Returns:
 /// false if the command can not be found else true. The result
 /// should be freed with free().
-bool path_get_path(const wcstring &cmd, wcstring *output_or_NULL,
+bool path_get_path(const wcstring &cmd, wcstring *output_or_NULL, const environment_t &vars);
-                   const environment_t &vars = env_vars_snapshot_t::current());
 
 /// Return all the paths that match the given command.
 wcstring_list_t path_get_paths(const wcstring &cmd);