From 04fe8bde15d80907b1350eda5834cebabbaf2f0f Mon Sep 17 00:00:00 2001
From: Gal Schlezinger <gal@spitfire.co.il>
Date: Sat, 19 Nov 2022 21:13:59 +0200
Subject: [PATCH] implement on all big shells woohoo

---
 src/shell/bash.rs            | 24 +++++++++++++++++++++++-
 src/shell/fish.rs            | 10 ++++++++++
 src/shell/mod.rs             |  1 -
 src/shell/powershell.rs      | 10 ++++++++++
 src/shell/trap_add_script.rs | 31 -------------------------------
 src/shell/zsh.rs             | 10 +++++++---
 6 files changed, 50 insertions(+), 36 deletions(-)
 delete mode 100644 src/shell/trap_add_script.rs

diff --git a/src/shell/bash.rs b/src/shell/bash.rs
index 7fcc8d3..35b4b20 100644
--- a/src/shell/bash.rs
+++ b/src/shell/bash.rs
@@ -1,6 +1,6 @@
 use crate::version_file_strategy::VersionFileStrategy;
 
-use super::{shell::Shell, trap_add_script::TRAP_ADD};
+use super::shell::Shell;
 use indoc::{formatdoc, indoc};
 use std::path::Path;
 
@@ -64,3 +64,25 @@ impl Shell for Bash {
         ))
     }
 }
+
+/// This code is based on Richard Hansen's answer on StackOverflow:
+/// https://stackoverflow.com/a/7287873/1176984
+///
+/// Usage:
+/// __fnm_trap_add__ 'echo "hello"' EXIT
+pub const TRAP_ADD: &'static str = indoc::indoc!(
+    r#"
+    __fnm_trap_add__() {
+        __fnm_trap_add___cmd=$1; shift || fatal "${FUNCNAME} usage error"
+        for __fnm_trap_add___name in "$@"; do
+            trap -- "$(
+                extract_trap_cmd() { printf '%s\n' "$3"; }
+                eval "extract_trap_cmd $(trap -p "${__fnm_trap_add___name}")"
+                printf '%s\n' "${__fnm_trap_add___cmd}"
+            )" "${__fnm_trap_add___name}" \
+                || fatal "unable to add to trap ${__fnm_trap_add___name}"
+        done
+    }
+    declare -f -t __fnm_trap_add__
+    "#
+);
diff --git a/src/shell/fish.rs b/src/shell/fish.rs
index 8856407..8f91c3d 100644
--- a/src/shell/fish.rs
+++ b/src/shell/fish.rs
@@ -46,4 +46,14 @@ impl Shell for Fish {
             autoload_hook = autoload_hook
         ))
     }
+
+    fn delete_on_exit(&self, fnm_multishell: &Path) -> Option<String> {
+        Some(indoc::formatdoc! {r#"
+            function _fnm_delete_multishell --on-event fish_exit
+                rm -f "{fnm_multishell}"
+            end
+
+            _fnm_delete_multishell
+        "#, fnm_multishell = fnm_multishell.display()})
+    }
 }
diff --git a/src/shell/mod.rs b/src/shell/mod.rs
index e74452f..4e27cd0 100644
--- a/src/shell/mod.rs
+++ b/src/shell/mod.rs
@@ -7,7 +7,6 @@ mod zsh;
 
 #[allow(clippy::module_inception)]
 mod shell;
-mod trap_add_script;
 
 pub use bash::Bash;
 pub use fish::Fish;
diff --git a/src/shell/powershell.rs b/src/shell/powershell.rs
index d3c8817..949130e 100644
--- a/src/shell/powershell.rs
+++ b/src/shell/powershell.rs
@@ -45,6 +45,16 @@ impl Shell for PowerShell {
             autoload_hook = autoload_hook
         ))
     }
+
+    fn delete_on_exit(&self, fnm_multishell: &Path) -> Option<String> {
+        Some(indoc::formatdoc!(
+            r#"
+                Register-EngineEvent PowerShell.Exiting -Action {{ rm "{fnm_multishell}" > $null }} > $null
+            "#,
+            fnm_multishell = fnm_multishell.display()
+        ))
+    }
+
     fn to_clap_shell(&self) -> clap_complete::Shell {
         clap_complete::Shell::PowerShell
     }
diff --git a/src/shell/trap_add_script.rs b/src/shell/trap_add_script.rs
deleted file mode 100644
index de38262..0000000
--- a/src/shell/trap_add_script.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-// This code is based on Richard Hansen's answer on StackOverflow:
-// https://stackoverflow.com/a/7287873/1176984
-
-pub const TRAP_ADD: &'static str = indoc::indoc!(
-    r#"
-    # appends a command to a trap
-    #
-    # - 1st arg:  code to add
-    # - remaining args:  names of traps to modify
-    #
-    __fnm_trap_add__() {
-        __fnm_trap_add___cmd=$1; shift || fatal "${FUNCNAME} usage error"
-        for __fnm_trap_add___name in "$@"; do
-            trap -- "$(
-                # helper fn to get existing trap command from output
-                # of trap -p
-                extract_trap_cmd() { printf '%s\n' "$3"; }
-                # print existing trap command with newline
-                eval "extract_trap_cmd $(trap -p "${__fnm_trap_add___name}")"
-                # print the new trap command
-                printf '%s\n' "${__fnm_trap_add___cmd}"
-            )" "${__fnm_trap_add___name}" \
-                || fatal "unable to add to trap ${__fnm_trap_add___name}"
-        done
-    }
-    # set the trace attribute for the above function.  this is
-    # required to modify DEBUG or RETURN traps because functions don't
-    # inherit them unless the trace attribute is set
-    declare -f -t __fnm_trap_add__
-    "#
-);
diff --git a/src/shell/zsh.rs b/src/shell/zsh.rs
index 91fcc6f..ebc19dc 100644
--- a/src/shell/zsh.rs
+++ b/src/shell/zsh.rs
@@ -55,11 +55,15 @@ impl Shell for Zsh {
     fn delete_on_exit(&self, fnm_multishell: &Path) -> Option<String> {
         Some(indoc::formatdoc!(
             r#"
-            {TRAP_ADD}
-            __fnm_trap_add__ 'rm "{fnm_multishell}"' EXIT
+                autoload -U add-zsh-hook
+                _fnm_on_exit () {{
+                    rm -f "{fnm_multishell}"
+                }}
+
+                add-zsh-hook zshexit _fnm_on_exit \
+                    && _fnm_on_exit
             "#,
             fnm_multishell = fnm_multishell.display(),
-            TRAP_ADD = super::trap_add_script::TRAP_ADD
         ))
     }
 }