import merge_derive-0.1.0 am: 9e8cac59d9

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/merge_derive/+/2336104

Change-Id: I1429ab845264fcaea17a9b4e53fa210735660176
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

10 files changed, 453 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..954a873
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,8 @@
+<!---
+SPDX-FileCopyrightText: 2020 Robin Krahl <robin.krahl@ireas.org>
+SPDX-License-Identifier: CC0-1.0
+-->
+
+# v0.1.0 (2020-09-01)
+
+Initial release providing a derive macro for the `Merge` trait.
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..2e33871
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,37 @@
+# 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 believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "merge_derive"
+version = "0.1.0"
+authors = ["Robin Krahl <robin.krahl@ireas.org>"]
+description = "Derive macro for the merge::Merge trait"
+readme = "README.md"
+keywords = ["merge", "macros", "derive"]
+categories = ["rust-patterns"]
+license = "Apache-2.0 OR MIT"
+repository = "https://git.sr.ht/~ireas/merge-rs/tree/master/merge_derive"
+
+[lib]
+proc-macro = true
+[dependencies.proc-macro-error]
+version = "1.0"
+
+[dependencies.proc-macro2]
+version = "1.0"
+
+[dependencies.quote]
+version = "1.0"
+
+[dependencies.syn]
+version = "1.0"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..d68eb20
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,23 @@
+# SPDX-FileCopyrightText: 2020 Robin Krahl <robin.krahl@ireas.org>
+# SPDX-License-Identifier: CC0-1.0
+
+[package]
+name = "merge_derive"
+version = "0.1.0"
+authors = ["Robin Krahl <robin.krahl@ireas.org>"]
+edition = "2018"
+description = "Derive macro for the merge::Merge trait"
+repository = "https://git.sr.ht/~ireas/merge-rs/tree/master/merge_derive"
+keywords = ["merge", "macros", "derive"]
+categories = ["rust-patterns"]
+readme = "README.md"
+license = "Apache-2.0 OR MIT"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0"
+proc-macro-error = "1.0"
+quote = "1.0"
+syn = "1.0"
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..5431dc1
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSES/Apache-2.0.txt
\ No newline at end of file
diff --git a/LICENSES/Apache-2.0.txt b/LICENSES/Apache-2.0.txt
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/LICENSES/Apache-2.0.txt
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..ac11bed
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,19 @@
+name: "merge_derive"
+description: "Derive macro for the merge::Merge trait"
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/merge_derive"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/merge_derive/merge_derive-0.1.0.crate"
+  }
+  version: "0.1.0"
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2022
+    month: 11
+    day: 28
+  }
+}
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..4e1e118
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,2 @@
+include platform/prebuilts/rust:master:/OWNERS
+fmayle@google.com
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..7913ba4
--- /dev/null
+++ b/README.md
@@ -0,0 +1,11 @@
+<!---
+Copyright (C) 2020 Robin Krahl <robin.krahl@ireas.org>
+SPDX-License-Identifier: CC0-1.0
+-->
+
+# merge-derive-rs
+
+This crate provides a derive macro for the `merge::Merge` crate.  See the
+[`merge`][] crate for more information.
+
+[`merge`]: https://lib.rs/crates/merge
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..75732f9
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,150 @@
+// SPDX-FileCopyrightText: 2020 Robin Krahl <robin.krahl@ireas.org>
+// SPDX-License-Identifier: Apache-2.0 or MIT
+
+//! A derive macro for the [`merge::Merge`][] trait.
+//!
+//! See the documentation for the [`merge`][] crate for more information.
+//!
+//! [`merge`]: https://lib.rs/crates/merge
+//! [`merge::Merge`]: https://docs.rs/merge/latest/merge/trait.Merge.html
+
+extern crate proc_macro;
+
+use proc_macro2::TokenStream;
+use proc_macro_error::{abort, abort_call_site, dummy::set_dummy, proc_macro_error, ResultExt};
+use quote::{quote, quote_spanned};
+use syn::Token;
+
+struct Field {
+    name: syn::Member,
+    span: proc_macro2::Span,
+    attrs: FieldAttrs,
+}
+
+#[derive(Default)]
+struct FieldAttrs {
+    skip: bool,
+    strategy: Option<syn::Path>,
+}
+
+enum FieldAttr {
+    Skip,
+    Strategy(syn::Path),
+}
+
+#[proc_macro_derive(Merge, attributes(merge))]
+#[proc_macro_error]
+pub fn merge_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    let ast = syn::parse(input).unwrap();
+    impl_merge(&ast).into()
+}
+
+fn impl_merge(ast: &syn::DeriveInput) -> TokenStream {
+    let name = &ast.ident;
+
+    set_dummy(quote! {
+        impl ::merge::Merge for #name {
+            fn merge(&mut self, other: Self) {
+                unimplemented!()
+            }
+        }
+    });
+
+    if let syn::Data::Struct(syn::DataStruct { ref fields, .. }) = ast.data {
+        impl_merge_for_struct(name, fields)
+    } else {
+        abort_call_site!("merge::Merge can only be derived for structs")
+    }
+}
+
+fn impl_merge_for_struct(name: &syn::Ident, fields: &syn::Fields) -> TokenStream {
+    let assignments = gen_assignments(fields);
+
+    quote! {
+        impl ::merge::Merge for #name {
+            fn merge(&mut self, other: Self) {
+                #assignments
+            }
+        }
+    }
+}
+
+fn gen_assignments(fields: &syn::Fields) -> TokenStream {
+    let fields = fields.iter().enumerate().map(Field::from);
+    let assignments = fields.filter(|f| !f.attrs.skip).map(|f| gen_assignment(&f));
+    quote! {
+        #( #assignments )*
+    }
+}
+
+fn gen_assignment(field: &Field) -> TokenStream {
+    use syn::spanned::Spanned;
+
+    let name = &field.name;
+    if let Some(strategy) = &field.attrs.strategy {
+        quote_spanned!(strategy.span()=> #strategy(&mut self.#name, other.#name);)
+    } else {
+        quote_spanned!(field.span=> ::merge::Merge::merge(&mut self.#name, other.#name);)
+    }
+}
+
+impl From<(usize, &syn::Field)> for Field {
+    fn from(data: (usize, &syn::Field)) -> Self {
+        use syn::spanned::Spanned;
+
+        let (index, field) = data;
+        Field {
+            name: if let Some(ident) = &field.ident {
+                syn::Member::Named(ident.clone())
+            } else {
+                syn::Member::Unnamed(index.into())
+            },
+            span: field.span(),
+            attrs: field.attrs.iter().into(),
+        }
+    }
+}
+
+impl FieldAttrs {
+    fn apply(&mut self, attr: FieldAttr) {
+        match attr {
+            FieldAttr::Skip => self.skip = true,
+            FieldAttr::Strategy(path) => self.strategy = Some(path),
+        }
+    }
+}
+
+impl<'a, I: Iterator<Item = &'a syn::Attribute>> From<I> for FieldAttrs {
+    fn from(iter: I) -> Self {
+        let mut field_attrs = Self::default();
+
+        for attr in iter {
+            if !attr.path.is_ident("merge") {
+                continue;
+            }
+
+            let parser = syn::punctuated::Punctuated::<FieldAttr, Token![,]>::parse_terminated;
+            for attr in attr.parse_args_with(parser).unwrap_or_abort() {
+                field_attrs.apply(attr);
+            }
+        }
+
+        field_attrs
+    }
+}
+
+impl syn::parse::Parse for FieldAttr {
+    fn parse(input: syn::parse::ParseStream) -> syn::parse::Result<Self> {
+        let name: syn::Ident = input.parse()?;
+        if name == "skip" {
+            // TODO check remaining stream
+            Ok(FieldAttr::Skip)
+        } else if name == "strategy" {
+            let _: Token![=] = input.parse()?;
+            let path: syn::Path = input.parse()?;
+            Ok(FieldAttr::Strategy(path))
+        } else {
+            abort!(name, "Unexpected attribute: {}", name)
+        }
+    }
+}