Import platform/external/rust/crates/zeroize_derive am: f8b8d0ff3b am: 0ec6ce0e1b am: a6bb55d980

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/zeroize_derive/+/2240635

Change-Id: Id9fb3b3e91de1a77ec8142b0a4af137c5c32b7fe
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

13 files changed, 1231 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..68eac09
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,6 @@
+{
+  "git": {
+    "sha1": "25167758af1fcbb8f5ee00c8d8097a50269635f5"
+  },
+  "path_in_vcs": "zeroize/derive"
+}
\ No newline at end of file
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..6ffcf50
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,20 @@
+// This file is generated by cargo2android.py --config cargo2android.json.
+// Do not modify this file as changes will be overridden on upgrade.
+
+
+
+rust_proc_macro {
+    name: "libzeroize_derive",
+    crate_name: "zeroize_derive",
+    cargo_env_compat: true,
+    cargo_pkg_version: "1.3.2",
+    srcs: ["src/lib.rs"],
+    edition: "2018",
+    rustlibs: [
+        "libproc_macro2",
+        "libquote",
+        "libsyn",
+        "libsynstructure",
+    ],
+    compile_multilib: "first",
+}
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..1ecaef2
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,57 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## 1.3.2 (2022-02-18)
+### Fixed
+- Min versions build ([#732])
+
+[#732]: https://github.com/RustCrypto/utils/pull/732
+
+## 1.3.1 (2021-01-14) [YANKED]
+### Removed
+- `ZeroizeOnDrop` implementation for `#[zeroize(drop)]` ([#715])
+
+[#715]: https://github.com/RustCrypto/utils/pull/715
+
+## 1.3.0 (2021-01-14) [YANKED]
+### Added
+- `#[zeroize(bound = "T: MyTrait")]` ([#663])
+- Custom derive for `ZeroizeOnDrop` ([#699], [#700])
+
+[#663]: https://github.com/RustCrypto/utils/pull/663
+[#699]: https://github.com/RustCrypto/utils/pull/699
+[#700]: https://github.com/RustCrypto/utils/pull/700
+
+## 1.2.2 (2021-11-04)
+### Added
+- `#[zeroize(skip)]` attribute ([#654])
+
+[#654]: https://github.com/RustCrypto/utils/pull/654
+
+## 1.2.1 (2021-11-04)
+### Changed
+- Moved to `RustCrypto/utils` repository
+
+## 1.2.0 (2021-09-21)
+### Changed
+- Bump MSRV to 1.51+
+- Reject `#[zeroize(drop)]` on struct/enum fields, enum variants
+
+## 1.1.1 (2021-10-09)
+### Changed
+- Backport 1.2.0 `#[zeroize(drop)]` fixes but with a 1.47+ MSRV.
+
+## 1.1.0 (2021-04-19)
+### Changed
+- Bump MSRV to 1.47+
+
+## 1.0.1 (2019-09-15)
+### Added
+- Add docs for the `Zeroize` proc macro
+
+## 1.0.0 (2019-10-13)
+
+- Initial 1.0 release
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..2cb23a0
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,38 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2018"
+name = "zeroize_derive"
+version = "1.3.2"
+authors = ["The RustCrypto Project Developers"]
+description = "Custom derive support for zeroize"
+readme = "README.md"
+keywords = ["memory", "memset", "secure", "volatile", "zero"]
+categories = ["cryptography", "memory-management", "no-std", "os"]
+license = "Apache-2.0 OR MIT"
+repository = "https://github.com/RustCrypto/utils/tree/master/zeroize/derive"
+[package.metadata.docs.rs]
+rustdoc-args = ["--document-private-items"]
+
+[lib]
+proc-macro = true
+[dependencies.proc-macro2]
+version = "1"
+
+[dependencies.quote]
+version = "1"
+
+[dependencies.syn]
+version = "1"
+
+[dependencies.synstructure]
+version = "0.12.2"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..4bac91a
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,23 @@
+[package]
+name = "zeroize_derive"
+description = "Custom derive support for zeroize"
+version = "1.3.2"
+authors = ["The RustCrypto Project Developers"]
+license = "Apache-2.0 OR MIT"
+repository = "https://github.com/RustCrypto/utils/tree/master/zeroize/derive"
+readme = "README.md"
+categories = ["cryptography", "memory-management", "no-std", "os"]
+keywords = ["memory", "memset", "secure", "volatile", "zero"]
+edition = "2018"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1"
+quote = "1"
+syn = "1"
+synstructure = "0.12.2"
+
+[package.metadata.docs.rs]
+rustdoc-args = ["--document-private-items"]
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,202 @@
+
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+      whether in tort (including negligence), contract, or otherwise,
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diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..3ec5f4c
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,20 @@
+name: "zeroize_derive"
+description: "Custom derive support for zeroize"
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/zeroize_derive"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/zeroize_derive/zeroize_derive-1.3.2.crate"
+  }
+  version: "1.3.2"
+  # Dual-licensed, using the least restrictive per go/thirdpartylicenses#same.
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2022
+    month: 9
+    day: 6
+  }
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..45dc4dd
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+include platform/prebuilts/rust:master:/OWNERS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..d5b16e3
--- /dev/null
+++ b/README.md
@@ -0,0 +1,49 @@
+# [RustCrypto]: `zeroize_derive`
+
+[![Crate][crate-image]][crate-link]
+![Apache 2.0 Licensed/MIT][license-image]
+![MSRV][rustc-image]
+[![Build Status][build-image]][build-link]
+
+Custom derive support for [zeroize]: a crate for securely zeroing memory
+while avoiding compiler optimizations.
+
+This crate isn't intended to be used directly.
+See [zeroize] crate for documentation.
+
+## Minimum Supported Rust Version
+
+Rust **1.51** or newer.
+
+In the future, we reserve the right to change MSRV (i.e. MSRV is out-of-scope
+for this crate's SemVer guarantees), however when we do it will be accompanied by
+a minor version bump.
+
+## License
+
+Licensed under either of:
+
+* [Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)
+* [MIT license](http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
+
+[//]: # (badges)
+
+[crate-image]: https://img.shields.io/crates/v/zeroize_derive.svg
+[crate-link]: https://crates.io/crates/zeroize_derive
+[license-image]: https://img.shields.io/badge/license-Apache2.0/MIT-blue.svg
+[rustc-image]: https://img.shields.io/badge/rustc-1.51+-blue.svg
+[build-image]: https://github.com/RustCrypto/utils/actions/workflows/zeroize.yml/badge.svg
+[build-link]: https://github.com/RustCrypto/utils/actions/workflows/zeroize.yml
+
+[//]: # (general links)
+
+[RustCrypto]: https://github.com/RustCrypto
+[zeroize]: https://github.com/RustCrypto/utils/tree/master/zeroize
diff --git a/cargo2android.json b/cargo2android.json
new file mode 100644
index 0000000..58e46ee
--- /dev/null
+++ b/cargo2android.json
@@ -0,0 +1,4 @@
+{
+  "host-first-multilib": true,
+  "run": true
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..1efc3b4
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,810 @@
+//! Custom derive support for `zeroize`
+
+#![crate_type = "proc-macro"]
+#![forbid(unsafe_code)]
+#![warn(rust_2018_idioms, trivial_casts, unused_qualifications)]
+
+use proc_macro2::TokenStream;
+use quote::quote;
+use syn::{
+    parse::{Parse, ParseStream},
+    punctuated::Punctuated,
+    token::Comma,
+    Attribute, Lit, Meta, NestedMeta, Result, WherePredicate,
+};
+use synstructure::{decl_derive, AddBounds, BindStyle, BindingInfo, VariantInfo};
+
+decl_derive!(
+    [Zeroize, attributes(zeroize)] =>
+
+    /// Derive the `Zeroize` trait.
+    ///
+    /// Supports the following attributes:
+    ///
+    /// On the item level:
+    /// - `#[zeroize(drop)]`: *deprecated* use `ZeroizeOnDrop` instead
+    /// - `#[zeroize(bound = "T: MyTrait")]`: this replaces any trait bounds
+    ///   inferred by zeroize-derive
+    ///
+    /// On the field level:
+    /// - `#[zeroize(skip)]`: skips this field or variant when calling `zeroize()`
+    derive_zeroize
+);
+
+decl_derive!(
+    [ZeroizeOnDrop, attributes(zeroize)] =>
+
+    /// Derive the `ZeroizeOnDrop` trait.
+    ///
+    /// Supports the following attributes:
+    ///
+    /// On the field level:
+    /// - `#[zeroize(skip)]`: skips this field or variant when calling `zeroize()`
+    derive_zeroize_on_drop
+);
+
+/// Name of zeroize-related attributes
+const ZEROIZE_ATTR: &str = "zeroize";
+
+/// Custom derive for `Zeroize`
+fn derive_zeroize(mut s: synstructure::Structure<'_>) -> TokenStream {
+    let attributes = ZeroizeAttrs::parse(&s);
+
+    if let Some(bounds) = attributes.bound {
+        s.add_bounds(AddBounds::None);
+
+        for bound in bounds.0 {
+            s.add_where_predicate(bound);
+        }
+    }
+
+    // NOTE: These are split into named functions to simplify testing with
+    // synstructure's `test_derive!` macro.
+    if attributes.drop {
+        derive_zeroize_with_drop(s)
+    } else {
+        derive_zeroize_without_drop(s)
+    }
+}
+
+/// Custom derive for `ZeroizeOnDrop`
+fn derive_zeroize_on_drop(mut s: synstructure::Structure<'_>) -> TokenStream {
+    let zeroizers = generate_fields(&mut s, quote! { zeroize_or_on_drop });
+
+    let drop_impl = s.gen_impl(quote! {
+        gen impl Drop for @Self {
+            fn drop(&mut self) {
+                use zeroize::__internal::AssertZeroize;
+                use zeroize::__internal::AssertZeroizeOnDrop;
+                match self {
+                    #zeroizers
+                }
+            }
+        }
+    });
+
+    let zeroize_on_drop_impl = impl_zeroize_on_drop(&s);
+
+    quote! {
+        #drop_impl
+
+        #zeroize_on_drop_impl
+    }
+}
+
+/// Custom derive attributes for `Zeroize`
+#[derive(Default)]
+struct ZeroizeAttrs {
+    /// Derive a `Drop` impl which calls zeroize on this type
+    drop: bool,
+    /// Custom bounds as defined by the user
+    bound: Option<Bounds>,
+}
+
+/// Parsing helper for custom bounds
+struct Bounds(Punctuated<WherePredicate, Comma>);
+
+impl Parse for Bounds {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        Ok(Self(Punctuated::parse_terminated(input)?))
+    }
+}
+
+impl ZeroizeAttrs {
+    /// Parse attributes from the incoming AST
+    fn parse(s: &synstructure::Structure<'_>) -> Self {
+        let mut result = Self::default();
+
+        for attr in s.ast().attrs.iter() {
+            result.parse_attr(attr, None, None);
+        }
+        for v in s.variants().iter() {
+            // only process actual enum variants here, as we don't want to process struct attributes twice
+            if v.prefix.is_some() {
+                for attr in v.ast().attrs.iter() {
+                    result.parse_attr(attr, Some(v), None);
+                }
+            }
+            for binding in v.bindings().iter() {
+                for attr in binding.ast().attrs.iter() {
+                    result.parse_attr(attr, Some(v), Some(binding));
+                }
+            }
+        }
+
+        result
+    }
+
+    /// Parse attribute and handle `#[zeroize(...)]` attributes
+    fn parse_attr(
+        &mut self,
+        attr: &Attribute,
+        variant: Option<&VariantInfo<'_>>,
+        binding: Option<&BindingInfo<'_>>,
+    ) {
+        let meta_list = match attr
+            .parse_meta()
+            .unwrap_or_else(|e| panic!("error parsing attribute: {:?} ({})", attr, e))
+        {
+            Meta::List(list) => list,
+            _ => return,
+        };
+
+        // Ignore any non-zeroize attributes
+        if !meta_list.path.is_ident(ZEROIZE_ATTR) {
+            return;
+        }
+
+        for nested_meta in &meta_list.nested {
+            if let NestedMeta::Meta(meta) = nested_meta {
+                self.parse_meta(meta, variant, binding);
+            } else {
+                panic!("malformed #[zeroize] attribute: {:?}", nested_meta);
+            }
+        }
+    }
+
+    /// Parse `#[zeroize(...)]` attribute metadata (e.g. `drop`)
+    fn parse_meta(
+        &mut self,
+        meta: &Meta,
+        variant: Option<&VariantInfo<'_>>,
+        binding: Option<&BindingInfo<'_>>,
+    ) {
+        if meta.path().is_ident("drop") {
+            assert!(!self.drop, "duplicate #[zeroize] drop flags");
+
+            match (variant, binding) {
+                (_variant, Some(_binding)) => {
+                    // structs don't have a variant prefix, and only structs have bindings outside of a variant
+                    let item_kind = match variant.and_then(|variant| variant.prefix) {
+                        Some(_) => "enum",
+                        None => "struct",
+                    };
+                    panic!(
+                        concat!(
+                            "The #[zeroize(drop)] attribute is not allowed on {} fields. ",
+                            "Use it on the containing {} instead.",
+                        ),
+                        item_kind, item_kind,
+                    )
+                }
+                (Some(_variant), None) => panic!(concat!(
+                    "The #[zeroize(drop)] attribute is not allowed on enum variants. ",
+                    "Use it on the containing enum instead.",
+                )),
+                (None, None) => (),
+            };
+
+            self.drop = true;
+        } else if meta.path().is_ident("bound") {
+            assert!(self.bound.is_none(), "duplicate #[zeroize] bound flags");
+
+            match (variant, binding) {
+                (_variant, Some(_binding)) => {
+                    // structs don't have a variant prefix, and only structs have bindings outside of a variant
+                    let item_kind = match variant.and_then(|variant| variant.prefix) {
+                        Some(_) => "enum",
+                        None => "struct",
+                    };
+                    panic!(
+                        concat!(
+                            "The #[zeroize(bound)] attribute is not allowed on {} fields. ",
+                            "Use it on the containing {} instead.",
+                        ),
+                        item_kind, item_kind,
+                    )
+                }
+                (Some(_variant), None) => panic!(concat!(
+                    "The #[zeroize(bound)] attribute is not allowed on enum variants. ",
+                    "Use it on the containing enum instead.",
+                )),
+                (None, None) => {
+                    if let Meta::NameValue(meta_name_value) = meta {
+                        if let Lit::Str(lit) = &meta_name_value.lit {
+                            if lit.value().is_empty() {
+                                self.bound = Some(Bounds(Punctuated::new()));
+                            } else {
+                                self.bound = Some(lit.parse().unwrap_or_else(|e| {
+                                    panic!("error parsing bounds: {:?} ({})", lit, e)
+                                }));
+                            }
+
+                            return;
+                        }
+                    }
+
+                    panic!(concat!(
+                        "The #[zeroize(bound)] attribute expects a name-value syntax with a string literal value.",
+                        "E.g. #[zeroize(bound = \"T: MyTrait\")]."
+                    ))
+                }
+            }
+        } else if meta.path().is_ident("skip") {
+            if variant.is_none() && binding.is_none() {
+                panic!(concat!(
+                    "The #[zeroize(skip)] attribute is not allowed on a `struct` or `enum`. ",
+                    "Use it on a field or variant instead.",
+                ))
+            }
+        } else {
+            panic!("unknown #[zeroize] attribute type: {:?}", meta.path());
+        }
+    }
+}
+
+fn generate_fields(s: &mut synstructure::Structure<'_>, method: TokenStream) -> TokenStream {
+    s.bind_with(|_| BindStyle::RefMut);
+
+    s.filter_variants(|vi| {
+        let result = filter_skip(vi.ast().attrs, true);
+
+        // check for duplicate `#[zeroize(skip)]` attributes in nested variants
+        for field in vi.ast().fields {
+            filter_skip(&field.attrs, result);
+        }
+
+        result
+    })
+    .filter(|bi| filter_skip(&bi.ast().attrs, true))
+    .each(|bi| quote! { #bi.#method(); })
+}
+
+fn filter_skip(attrs: &[Attribute], start: bool) -> bool {
+    let mut result = start;
+
+    for attr in attrs.iter().filter_map(|attr| attr.parse_meta().ok()) {
+        if let Meta::List(list) = attr {
+            if list.path.is_ident(ZEROIZE_ATTR) {
+                for nested in list.nested {
+                    if let NestedMeta::Meta(Meta::Path(path)) = nested {
+                        if path.is_ident("skip") {
+                            assert!(result, "duplicate #[zeroize] skip flags");
+                            result = false;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    result
+}
+
+/// Custom derive for `Zeroize` (without `Drop`)
+fn derive_zeroize_without_drop(mut s: synstructure::Structure<'_>) -> TokenStream {
+    let zeroizers = generate_fields(&mut s, quote! { zeroize });
+
+    s.bound_impl(
+        quote!(zeroize::Zeroize),
+        quote! {
+            fn zeroize(&mut self) {
+                match self {
+                    #zeroizers
+                }
+            }
+        },
+    )
+}
+
+/// Custom derive for `Zeroize` and `Drop`
+fn derive_zeroize_with_drop(s: synstructure::Structure<'_>) -> TokenStream {
+    let drop_impl = s.gen_impl(quote! {
+        gen impl Drop for @Self {
+            fn drop(&mut self) {
+                self.zeroize();
+            }
+        }
+    });
+
+    let zeroize_impl = derive_zeroize_without_drop(s);
+
+    quote! {
+        #zeroize_impl
+
+        #[doc(hidden)]
+        #drop_impl
+    }
+}
+
+fn impl_zeroize_on_drop(s: &synstructure::Structure<'_>) -> TokenStream {
+    #[allow(unused_qualifications)]
+    s.bound_impl(quote!(zeroize::ZeroizeOnDrop), Option::<TokenStream>::None)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use syn::parse_str;
+    use synstructure::{test_derive, Structure};
+
+    #[test]
+    fn zeroize_without_drop() {
+        test_derive! {
+            derive_zeroize_without_drop {
+                struct Z {
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                }
+            }
+            expands to {
+                #[allow(non_upper_case_globals)]
+                #[doc(hidden)]
+                const _DERIVE_zeroize_Zeroize_FOR_Z: () = {
+                    extern crate zeroize;
+                    impl zeroize::Zeroize for Z {
+                        fn zeroize(&mut self) {
+                            match self {
+                                Z {
+                                    a: ref mut __binding_0,
+                                    b: ref mut __binding_1,
+                                    c: ref mut __binding_2,
+                                } => {
+                                    { __binding_0.zeroize(); }
+                                    { __binding_1.zeroize(); }
+                                    { __binding_2.zeroize(); }
+                                }
+                            }
+                        }
+                    }
+                };
+            }
+            no_build // tests the code compiles are in the `zeroize` crate
+        }
+    }
+
+    #[test]
+    fn zeroize_with_drop() {
+        test_derive! {
+            derive_zeroize_with_drop {
+                struct Z {
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                }
+            }
+            expands to {
+                #[allow(non_upper_case_globals)]
+                #[doc(hidden)]
+                const _DERIVE_zeroize_Zeroize_FOR_Z: () = {
+                    extern crate zeroize;
+                    impl zeroize::Zeroize for Z {
+                        fn zeroize(&mut self) {
+                            match self {
+                                Z {
+                                    a: ref mut __binding_0,
+                                    b: ref mut __binding_1,
+                                    c: ref mut __binding_2,
+                                } => {
+                                    { __binding_0.zeroize(); }
+                                    { __binding_1.zeroize(); }
+                                    { __binding_2.zeroize(); }
+                                }
+                            }
+                        }
+                    }
+                };
+                #[doc(hidden)]
+                #[allow(non_upper_case_globals)]
+                const _DERIVE_Drop_FOR_Z: () = {
+                    impl Drop for Z {
+                        fn drop(&mut self) {
+                            self.zeroize();
+                        }
+                    }
+                };
+            }
+            no_build // tests the code compiles are in the `zeroize` crate
+        }
+    }
+
+    #[test]
+    fn zeroize_with_skip() {
+        test_derive! {
+            derive_zeroize_without_drop {
+                struct Z {
+                    a: String,
+                    b: Vec<u8>,
+                    #[zeroize(skip)]
+                    c: [u8; 3],
+                }
+            }
+            expands to {
+                #[allow(non_upper_case_globals)]
+                #[doc(hidden)]
+                const _DERIVE_zeroize_Zeroize_FOR_Z: () = {
+                    extern crate zeroize;
+                    impl zeroize::Zeroize for Z {
+                        fn zeroize(&mut self) {
+                            match self {
+                                Z {
+                                    a: ref mut __binding_0,
+                                    b: ref mut __binding_1,
+                                    ..
+                                } => {
+                                    { __binding_0.zeroize(); }
+                                    { __binding_1.zeroize(); }
+                                }
+                            }
+                        }
+                    }
+                };
+            }
+            no_build // tests the code compiles are in the `zeroize` crate
+        }
+    }
+
+    #[test]
+    fn zeroize_with_bound() {
+        test_derive! {
+            derive_zeroize {
+                #[zeroize(bound = "T: MyTrait")]
+                struct Z<T>(T);
+            }
+            expands to {
+                #[allow(non_upper_case_globals)]
+                #[doc(hidden)]
+                const _DERIVE_zeroize_Zeroize_FOR_Z: () = {
+                    extern crate zeroize;
+                    impl<T> zeroize::Zeroize for Z<T>
+                    where T: MyTrait
+                    {
+                        fn zeroize(&mut self) {
+                            match self {
+                                Z(ref mut __binding_0,) => {
+                                    { __binding_0.zeroize(); }
+                                }
+                            }
+                        }
+                    }
+                };
+            }
+            no_build // tests the code compiles are in the `zeroize` crate
+        }
+    }
+
+    #[test]
+    fn zeroize_only_drop() {
+        test_derive! {
+            derive_zeroize_on_drop {
+                struct Z {
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                }
+            }
+            expands to {
+                #[allow(non_upper_case_globals)]
+                const _DERIVE_Drop_FOR_Z: () = {
+                    impl Drop for Z {
+                        fn drop(&mut self) {
+                            use zeroize::__internal::AssertZeroize;
+                            use zeroize::__internal::AssertZeroizeOnDrop;
+                            match self {
+                                Z {
+                                    a: ref mut __binding_0,
+                                    b: ref mut __binding_1,
+                                    c: ref mut __binding_2,
+                                } => {
+                                    { __binding_0.zeroize_or_on_drop(); }
+                                    { __binding_1.zeroize_or_on_drop(); }
+                                    { __binding_2.zeroize_or_on_drop(); }
+                                }
+                            }
+                        }
+                    }
+                };
+                #[allow(non_upper_case_globals)]
+                #[doc(hidden)]
+                const _DERIVE_zeroize_ZeroizeOnDrop_FOR_Z: () = {
+                    extern crate zeroize;
+                    impl zeroize::ZeroizeOnDrop for Z {}
+                };
+            }
+            no_build // tests the code compiles are in the `zeroize` crate
+        }
+    }
+
+    #[test]
+    fn zeroize_on_struct() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(drop)]
+            struct Z {
+                a: String,
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    fn zeroize_on_enum() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(drop)]
+            enum Z {
+                Variant1 { a: String, b: Vec<u8>, c: [u8; 3] },
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on struct fields")]
+    fn zeroize_on_struct_field() {
+        parse_zeroize_test(stringify!(
+            struct Z {
+                #[zeroize(drop)]
+                a: String,
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on struct fields")]
+    fn zeroize_on_tuple_struct_field() {
+        parse_zeroize_test(stringify!(
+            struct Z(#[zeroize(drop)] String);
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on struct fields")]
+    fn zeroize_on_second_field() {
+        parse_zeroize_test(stringify!(
+            struct Z {
+                a: String,
+                #[zeroize(drop)]
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on enum fields")]
+    fn zeroize_on_tuple_enum_variant_field() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                Variant(#[zeroize(drop)] String),
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on enum fields")]
+    fn zeroize_on_enum_variant_field() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                Variant {
+                    #[zeroize(drop)]
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                },
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on enum fields")]
+    fn zeroize_on_enum_second_variant_field() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                Variant1 {
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                },
+                Variant2 {
+                    #[zeroize(drop)]
+                    a: String,
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                },
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on enum variants")]
+    fn zeroize_on_enum_variant() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                #[zeroize(drop)]
+                Variant,
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "#[zeroize(drop)] attribute is not allowed on enum variants")]
+    fn zeroize_on_enum_second_variant() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                Variant1,
+                #[zeroize(drop)]
+                Variant2,
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(skip)] attribute is not allowed on a `struct` or `enum`. Use it on a field or variant instead."
+    )]
+    fn zeroize_skip_on_struct() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(skip)]
+            struct Z {
+                a: String,
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(skip)] attribute is not allowed on a `struct` or `enum`. Use it on a field or variant instead."
+    )]
+    fn zeroize_skip_on_enum() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(skip)]
+            enum Z {
+                Variant1,
+                Variant2,
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "duplicate #[zeroize] skip flags")]
+    fn zeroize_duplicate_skip() {
+        parse_zeroize_test(stringify!(
+            struct Z {
+                a: String,
+                #[zeroize(skip)]
+                #[zeroize(skip)]
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "duplicate #[zeroize] skip flags")]
+    fn zeroize_duplicate_skip_list() {
+        parse_zeroize_test(stringify!(
+            struct Z {
+                a: String,
+                #[zeroize(skip, skip)]
+                b: Vec<u8>,
+                c: [u8; 3],
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "duplicate #[zeroize] skip flags")]
+    fn zeroize_duplicate_skip_enum() {
+        parse_zeroize_test(stringify!(
+            enum Z {
+                #[zeroize(skip)]
+                Variant {
+                    a: String,
+                    #[zeroize(skip)]
+                    b: Vec<u8>,
+                    c: [u8; 3],
+                },
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "duplicate #[zeroize] bound flags")]
+    fn zeroize_duplicate_bound() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(bound = "T: MyTrait")]
+            #[zeroize(bound = "")]
+            struct Z<T>(T);
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "duplicate #[zeroize] bound flags")]
+    fn zeroize_duplicate_bound_list() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(bound = "T: MyTrait", bound = "")]
+            struct Z<T>(T);
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(bound)] attribute is not allowed on struct fields. Use it on the containing struct instead."
+    )]
+    fn zeroize_bound_struct() {
+        parse_zeroize_test(stringify!(
+            struct Z<T> {
+                #[zeroize(bound = "T: MyTrait")]
+                a: T,
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(bound)] attribute is not allowed on enum variants. Use it on the containing enum instead."
+    )]
+    fn zeroize_bound_enum() {
+        parse_zeroize_test(stringify!(
+            enum Z<T> {
+                #[zeroize(bound = "T: MyTrait")]
+                A(T),
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(bound)] attribute is not allowed on enum fields. Use it on the containing enum instead."
+    )]
+    fn zeroize_bound_enum_variant_field() {
+        parse_zeroize_test(stringify!(
+            enum Z<T> {
+                A {
+                    #[zeroize(bound = "T: MyTrait")]
+                    a: T,
+                },
+            }
+        ));
+    }
+
+    #[test]
+    #[should_panic(
+        expected = "The #[zeroize(bound)] attribute expects a name-value syntax with a string literal value.E.g. #[zeroize(bound = \"T: MyTrait\")]."
+    )]
+    fn zeroize_bound_no_value() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(bound)]
+            struct Z<T>(T);
+        ));
+    }
+
+    #[test]
+    #[should_panic(expected = "error parsing bounds: LitStr { token: \"T\" } (expected `:`)")]
+    fn zeroize_bound_no_where_predicate() {
+        parse_zeroize_test(stringify!(
+            #[zeroize(bound = "T")]
+            struct Z<T>(T);
+        ));
+    }
+
+    fn parse_zeroize_test(unparsed: &str) -> TokenStream {
+        derive_zeroize(Structure::new(
+            &parse_str(unparsed).expect("Failed to parse test input"),
+        ))
+    }
+}