status fish-path: Remove "(deleted)" suffix

Fixes #9018.

(cherry picked from commit 6e0653af93)

CHANGELOG.rst

@@ -5,6 +5,7 @@ This release of fish fixes a number of problems identified in fish 3.5.0.
 
 - Completing ``git blame`` or ``git -C`` works correctly (:issue:`9053`).
 - On terminals that emit a ``CSI u`` sequence for :kbd:`Shift-Space`, fish inserts a space instead of printing an error. (:issue:`9054`).
+- ``status fish-path`` on Linux-based platforms could print the path with a " (deleted)" suffix (such as ``/usr/bin/fish (deleted)``), which is now removed (:issue:`9019`).
 
 --------------
 

src/common.cpp

@@ -1900,7 +1900,17 @@ std::string get_executable_path(const char *argv0) {
     }
     if (len > 0) {
         buff[len] = '\0';
-        return std::string(buff);
+        // When /proc/self/exe points to a file that was deleted (or overwritten on update!)
+        // then linux adds a " (deleted)" suffix.
+        // If that's not a valid path, let's remove that awkward suffix.
+        std::string buffstr{buff};
+        if (access(buff, F_OK)) {
+            auto dellen = const_strlen(" (deleted)");
+            if (buffstr.size() > dellen && buffstr.compare(buffstr.size() - dellen, dellen, " (deleted)") == 0) {
+                buffstr = buffstr.substr(0, buffstr.size() - const_strlen(" (deleted)"));
+            }
+        }
+        return buffstr;
     }
 #endif