From 436e1f9abf4cdfac21fb9cb2061b96b0b8d5ea6e Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Mon, 27 Jun 2022 20:26:25 -0500
Subject: [PATCH] WIP: fix: Ensure 'ArgMatches' is unwind safe

Fixes #3876
---
 src/builder/command.rs            |  8 +++++-
 src/builder/value_parser.rs       | 21 +++++++++++---
 src/parser/matches/any_value.rs   | 37 ++++++++++++++++++++++---
 src/parser/matches/arg_matches.rs | 46 +++++++++++++++++++++++++------
 4 files changed, 94 insertions(+), 18 deletions(-)

diff --git a/src/builder/command.rs b/src/builder/command.rs
index bbd14dc6caf..cc046890fa8 100644
--- a/src/builder/command.rs
+++ b/src/builder/command.rs
@@ -5110,5 +5110,11 @@ where
 
 #[test]
 fn check_auto_traits() {
-    static_assertions::assert_impl_all!(Command: Send, Sync, Unpin);
+    static_assertions::assert_impl_all!(
+        Command: Send,
+        Sync,
+        std::panic::RefUnwindSafe,
+        std::panic::UnwindSafe,
+        Unpin
+    );
 }
diff --git a/src/builder/value_parser.rs b/src/builder/value_parser.rs
index 397537c9f52..60729da5764 100644
--- a/src/builder/value_parser.rs
+++ b/src/builder/value_parser.rs
@@ -108,7 +108,7 @@ impl ValueParser {
     pub fn new<P>(other: P) -> Self
     where
         P: TypedValueParser,
-        P::Value: Send + Sync + Clone,
+        P::Value: Send + Sync + Clone + std::panic::UnwindSafe + std::panic::RefUnwindSafe,
     {
         Self(ValueParserInner::Other(Box::new(other)))
     }
@@ -284,7 +284,7 @@ impl ValueParser {
 impl<P> From<P> for ValueParser
 where
     P: TypedValueParser + Send + Sync + 'static,
-    P::Value: Send + Sync + Clone,
+    P::Value: Send + Sync + Clone + std::panic::UnwindSafe + std::panic::RefUnwindSafe,
 {
     fn from(p: P) -> Self {
         Self::new(p)
@@ -563,7 +563,13 @@ trait AnyValueParser: Send + Sync + 'static {
 
 impl<T, P> AnyValueParser for P
 where
-    T: std::any::Any + Clone + Send + Sync + 'static,
+    T: std::any::Any
+        + Clone
+        + Send
+        + Sync
+        + std::panic::UnwindSafe
+        + std::panic::RefUnwindSafe
+        + 'static,
     P: TypedValueParser<Value = T>,
 {
     fn parse_ref(
@@ -1963,7 +1969,14 @@ pub mod via_prelude {
     }
     impl<FromStr> _ValueParserViaFromStr for _AutoValueParser<FromStr>
     where
-        FromStr: std::str::FromStr + std::any::Any + Clone + Send + Sync + 'static,
+        FromStr: std::str::FromStr
+            + std::any::Any
+            + Clone
+            + Send
+            + Sync
+            + std::panic::UnwindSafe
+            + std::panic::RefUnwindSafe
+            + 'static,
         <FromStr as std::str::FromStr>::Err:
             Into<Box<dyn std::error::Error + Send + Sync + 'static>>,
     {
diff --git a/src/parser/matches/any_value.rs b/src/parser/matches/any_value.rs
index a9277e75fa8..39bbc180754 100644
--- a/src/parser/matches/any_value.rs
+++ b/src/parser/matches/any_value.rs
@@ -1,25 +1,54 @@
 #[derive(Clone)]
 pub(crate) struct AnyValue {
-    inner: std::sync::Arc<dyn std::any::Any + Send + Sync + 'static>,
+    inner: std::sync::Arc<
+        dyn std::any::Any
+            + Send
+            + Sync
+            + std::panic::UnwindSafe
+            + std::panic::RefUnwindSafe
+            + 'static,
+    >,
     // While we can extract `TypeId` from `inner`, the debug repr is of a number, so let's track
     // the type_name in debug builds.
     id: AnyValueId,
 }
 
 impl AnyValue {
-    pub(crate) fn new<V: std::any::Any + Clone + Send + Sync + 'static>(inner: V) -> Self {
+    pub(crate) fn new<
+        V: std::any::Any
+            + Clone
+            + Send
+            + Sync
+            + std::panic::UnwindSafe
+            + std::panic::RefUnwindSafe
+            + 'static,
+    >(
+        inner: V,
+    ) -> Self {
         let id = AnyValueId::of::<V>();
         let inner = std::sync::Arc::new(inner);
         Self { inner, id }
     }
 
-    pub(crate) fn downcast_ref<T: std::any::Any + Clone + Send + Sync + 'static>(
+    pub(crate) fn downcast_ref<
+        T: std::any::Any
+            + Clone
+            + Send
+            + Sync
+            + std::panic::UnwindSafe
+            + std::panic::RefUnwindSafe
+            + 'static,
+    >(
         &self,
     ) -> Option<&T> {
         self.inner.downcast_ref::<T>()
     }
 
-    pub(crate) fn downcast_into<T: std::any::Any + Clone + Send + Sync>(self) -> Result<T, Self> {
+    pub(crate) fn downcast_into<
+        T: std::any::Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe,
+    >(
+        self,
+    ) -> Result<T, Self> {
         let id = self.id;
         let value =
             std::sync::Arc::downcast::<T>(self.inner).map_err(|inner| Self { inner, id })?;
diff --git a/src/parser/matches/arg_matches.rs b/src/parser/matches/arg_matches.rs
index d0df68441ff..fc344170d65 100644
--- a/src/parser/matches/arg_matches.rs
+++ b/src/parser/matches/arg_matches.rs
@@ -114,7 +114,12 @@ impl ArgMatches {
     /// [positional]: crate::Arg::index()
     /// [`default_value`]: crate::Arg::default_value()
     #[track_caller]
-    pub fn get_one<T: Any + Clone + Send + Sync + 'static>(&self, id: &str) -> Option<&T> {
+    pub fn get_one<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
+        &self,
+        id: &str,
+    ) -> Option<&T> {
         let internal_id = Id::from(id);
         MatchesError::unwrap(&internal_id, self.try_get_one(id))
     }
@@ -153,7 +158,9 @@ impl ArgMatches {
     /// assert_eq!(vals, [22, 80, 2020]);
     /// ```
     #[track_caller]
-    pub fn get_many<T: Any + Clone + Send + Sync + 'static>(
+    pub fn get_many<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &self,
         id: &str,
     ) -> Option<ValuesRef<T>> {
@@ -243,7 +250,12 @@ impl ArgMatches {
     /// [positional]: crate::Arg::index()
     /// [`default_value`]: crate::Arg::default_value()
     #[track_caller]
-    pub fn remove_one<T: Any + Clone + Send + Sync + 'static>(&mut self, id: &str) -> Option<T> {
+    pub fn remove_one<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
+        &mut self,
+        id: &str,
+    ) -> Option<T> {
         let internal_id = Id::from(id);
         MatchesError::unwrap(&internal_id, self.try_remove_one(id))
     }
@@ -280,7 +292,9 @@ impl ArgMatches {
     /// assert_eq!(vals, ["file1.txt", "file2.txt", "file3.txt", "file4.txt"]);
     /// ```
     #[track_caller]
-    pub fn remove_many<T: Any + Clone + Send + Sync + 'static>(
+    pub fn remove_many<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &mut self,
         id: &str,
     ) -> Option<Values2<T>> {
@@ -1074,7 +1088,9 @@ impl ArgMatches {
 /// # Advanced
 impl ArgMatches {
     /// Non-panicking version of [`ArgMatches::get_one`]
-    pub fn try_get_one<T: Any + Clone + Send + Sync + 'static>(
+    pub fn try_get_one<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &self,
         id: &str,
     ) -> Result<Option<&T>, MatchesError> {
@@ -1093,7 +1109,9 @@ impl ArgMatches {
     }
 
     /// Non-panicking version of [`ArgMatches::get_many`]
-    pub fn try_get_many<T: Any + Clone + Send + Sync + 'static>(
+    pub fn try_get_many<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &self,
         id: &str,
     ) -> Result<Option<ValuesRef<T>>, MatchesError> {
@@ -1129,7 +1147,9 @@ impl ArgMatches {
     }
 
     /// Non-panicking version of [`ArgMatches::remove_one`]
-    pub fn try_remove_one<T: Any + Clone + Send + Sync + 'static>(
+    pub fn try_remove_one<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &mut self,
         id: &str,
     ) -> Result<Option<T>, MatchesError> {
@@ -1145,7 +1165,9 @@ impl ArgMatches {
     }
 
     /// Non-panicking version of [`ArgMatches::remove_many`]
-    pub fn try_remove_many<T: Any + Clone + Send + Sync + 'static>(
+    pub fn try_remove_many<
+        T: Any + Clone + Send + Sync + std::panic::UnwindSafe + std::panic::RefUnwindSafe + 'static,
+    >(
         &mut self,
         id: &str,
     ) -> Result<Option<Values2<T>>, MatchesError> {
@@ -1743,7 +1765,13 @@ mod tests {
 
     #[test]
     fn check_auto_traits() {
-        static_assertions::assert_impl_all!(ArgMatches: Send, Sync, Unpin);
+        static_assertions::assert_impl_all!(
+            ArgMatches: Send,
+            Sync,
+            std::panic::RefUnwindSafe,
+            std::panic::UnwindSafe,
+            Unpin
+        );
     }
 
     #[test]