Remove the shell option, always use /bin/sh

README.asciidoc

@@ -512,8 +512,6 @@ Some options are built in Kakoune, and can be used to control it's behaviour:
    writing a buffer, this is autodetected on load.
  * +BOM+ _string_ ("no" or "utf-8"): define if the file should be written
    with an unicode byte order mark.
- * +shell+ _string_ ("bash" by default): what command to run to evaluate
-   shell commands.
  * +complete_prefix+ _bool_: when completing in command line, and multiple
    candidates exist, enable completion with common prefix.
  * +incsearch+ _bool_: execute search as it is typed

src/option_manager.cc

@@ -125,7 +125,6 @@ GlobalOptions::GlobalOptions()
     declare_option<int>("scrolloff", 0);
     declare_option<String>("eolformat", "lf");
     declare_option<String>("BOM", "no");
-    declare_option<String>("shell", "bash");
     declare_option<bool>("complete_prefix", true);
     declare_option<bool>("incsearch", true);
     declare_option<bool>("autoinfo", true);

src/shell_manager.cc

@@ -119,7 +119,7 @@ String ShellManager::pipe(const String& input,
 
             ++it;
         }
-        String shell = context.options()["shell"].get<String>();
+        String shell = "/bin/sh";
         std::vector<const char*> execparams = { shell.c_str(), "-c", cmdline.c_str() };
         if (not params.empty())
             execparams.push_back(shell.c_str());