Initial import am: cbd0311724 am: 539e63f8e3 am: 8e737c8b71

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/enumn/+/1913488

Change-Id: Iebeca0158332742bb6cbedf1774f08810f3f5755

15 files changed, 667 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..ea3dd4d
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "30565e34c2a6e9ded85d27350b8a6c1e6207eb2c"
+  }
+}
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..385cd8e
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,21 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+  schedule: [cron: "40 1 * * *"]
+
+jobs:
+  test:
+    name: Rust ${{matrix.rust}}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        rust: [nightly, beta, stable, 1.31.0]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{matrix.rust}}
+      - run: cargo test
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..6936990
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/target
+**/*.rs.bk
+Cargo.lock
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..e613d58
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,18 @@
+// 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: "libenumn",
+    crate_name: "enumn",
+    cargo_env_compat: true,
+    cargo_pkg_version: "0.1.3",
+    srcs: ["src/lib.rs"],
+    edition: "2018",
+    rustlibs: [
+        "libproc_macro2",
+        "libquote",
+        "libsyn",
+    ],
+}
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..e68e67d
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,35 @@
+# 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 = "enumn"
+version = "0.1.3"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
+description = "Convert number to enum"
+documentation = "https://docs.rs/enumn"
+readme = "README.md"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/dtolnay/enumn"
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[lib]
+proc-macro = true
+[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..938bfe8
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,21 @@
+[package]
+name = "enumn"
+version = "0.1.3"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
+edition = "2018"
+license = "MIT OR Apache-2.0"
+description = "Convert number to enum"
+repository = "https://github.com/dtolnay/enumn"
+documentation = "https://docs.rs/enumn"
+readme = "README.md"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0"
+quote = "1.0"
+syn = "1.0"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
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..16fe87b
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,201 @@
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..31aa793
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
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+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..0cedc69
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,20 @@
+name: "enumn"
+description: "Convert number to enum"
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/enumn"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/enumn/enumn-0.1.3.crate"
+  }
+  version: "0.1.3"
+  # Dual-licensed, using the least restrictive per go/thirdpartylicenses#same.
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2021
+    month: 12
+    day: 2
+  }
+}
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..d931a6a
--- /dev/null
+++ b/README.md
@@ -0,0 +1,110 @@
+Convert number to enum
+======================
+
+[<img alt="github" src="https://img.shields.io/badge/github-dtolnay/enumn-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/enumn)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/enumn.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/enumn)
+[<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-enumn-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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" height="20">](https://docs.rs/enumn)
+[<img alt="build status" src="https://img.shields.io/github/workflow/status/dtolnay/enumn/CI/master?style=for-the-badge" height="20">](https://github.com/dtolnay/enumn/actions?query=branch%3Amaster)
+
+This crate provides a derive macro to generate a function for converting a
+primitive integer into the corresponding variant of an enum.
+
+The generated function is named `n` and has the following signature:
+
+```rust
+impl YourEnum {
+    pub fn n(value: Repr) -> Option<Self>;
+}
+```
+
+where `Repr` is an integer type of the right size as described in more
+detail below.
+
+## Example
+
+```rust
+use enumn::N;
+
+#[derive(PartialEq, Debug, N)]
+enum Status {
+    LegendaryTriumph,
+    QualifiedSuccess,
+    FortuitousRevival,
+    IndeterminateStalemate,
+    RecoverableSetback,
+    DireMisadventure,
+    AbjectFailure,
+}
+
+fn main() {
+    let s = Status::n(1);
+    assert_eq!(s, Some(Status::QualifiedSuccess));
+
+    let s = Status::n(9);
+    assert_eq!(s, None);
+}
+```
+
+## Signature
+
+The generated signature depends on whether the enum has a `#[repr(..)]`
+attribute. If a `repr` is specified, the input to `n` will be required to be
+of that type.
+
+```rust
+#[derive(enumn::N)]
+#[repr(u8)]
+enum E {
+    /* ... */
+}
+
+// expands to:
+impl E {
+    pub fn n(value: u8) -> Option<Self> {
+        /* ... */
+    }
+}
+```
+
+On the other hand if no `repr` is specified then we get a signature that is
+generic over a variety of possible types.
+
+```rust
+impl E {
+    pub fn n<REPR: Into<i64>>(value: REPR) -> Option<Self> {
+        /* ... */
+    }
+}
+```
+
+## Discriminants
+
+The conversion respects explictly specified enum discriminants. Consider
+this enum:
+
+```rust
+#[derive(enumn::N)]
+enum Letter {
+    A = 65,
+    B = 66,
+}
+```
+
+Here `Letter::n(65)` would return `Some(Letter::A)`.
+
+<br>
+
+#### License
+
+<sup>
+Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
+2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
+</sup>
+
+<br>
+
+<sub>
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
+be dual licensed as above, without any additional terms or conditions.
+</sub>
diff --git a/cargo2android.json b/cargo2android.json
new file mode 100644
index 0000000..5c18d15
--- /dev/null
+++ b/cargo2android.json
@@ -0,0 +1,9 @@
+{
+  "apex-available": [
+    "//apex_available:platform",
+    "com.android.virt"
+  ],
+  "dependencies": true,
+  "device": true,
+  "run": true
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..9639ee2
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,199 @@
+//! [![github]](https://github.com/dtolnay/enumn)&ensp;[![crates-io]](https://crates.io/crates/enumn)&ensp;[![docs-rs]](https://docs.rs/enumn)
+//!
+//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
+//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
+//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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
+//!
+//! <br>
+//!
+//! Convert number to enum.
+//!
+//! This crate provides a derive macro to generate a function for converting a
+//! primitive integer into the corresponding variant of an enum.
+//!
+//! The generated function is named `n` and has the following signature:
+//!
+//! ```
+//! # const IGNORE: &str = stringify! {
+//! impl YourEnum {
+//!     pub fn n(value: Repr) -> Option<Self>;
+//! }
+//! # };
+//! ```
+//!
+//! where `Repr` is an integer type of the right size as described in more
+//! detail below.
+//!
+//! # Example
+//!
+//! ```
+//! use enumn::N;
+//!
+//! #[derive(PartialEq, Debug, N)]
+//! enum Status {
+//!     LegendaryTriumph,
+//!     QualifiedSuccess,
+//!     FortuitousRevival,
+//!     IndeterminateStalemate,
+//!     RecoverableSetback,
+//!     DireMisadventure,
+//!     AbjectFailure,
+//! }
+//!
+//! fn main() {
+//!     let s = Status::n(1);
+//!     assert_eq!(s, Some(Status::QualifiedSuccess));
+//!
+//!     let s = Status::n(9);
+//!     assert_eq!(s, None);
+//! }
+//! ```
+//!
+//! # Signature
+//!
+//! The generated signature depends on whether the enum has a `#[repr(..)]`
+//! attribute. If a `repr` is specified, the input to `n` will be required to be
+//! of that type.
+//!
+//! ```
+//! #[derive(enumn::N)]
+//! # enum E0 {
+//! #     IGNORE
+//! # }
+//! #
+//! #[repr(u8)]
+//! enum E {
+//!     /* ... */
+//!     # IGNORE
+//! }
+//!
+//! // expands to:
+//! impl E {
+//!     pub fn n(value: u8) -> Option<Self> {
+//!         /* ... */
+//!         # unimplemented!()
+//!     }
+//! }
+//! ```
+//!
+//! On the other hand if no `repr` is specified then we get a signature that is
+//! generic over a variety of possible types.
+//!
+//! ```
+//! # enum E {}
+//! #
+//! impl E {
+//!     pub fn n<REPR: Into<i64>>(value: REPR) -> Option<Self> {
+//!         /* ... */
+//!         # unimplemented!()
+//!     }
+//! }
+//! ```
+//!
+//! # Discriminants
+//!
+//! The conversion respects explictly specified enum discriminants. Consider
+//! this enum:
+//!
+//! ```
+//! #[derive(enumn::N)]
+//! enum Letter {
+//!     A = 65,
+//!     B = 66,
+//! }
+//! ```
+//!
+//! Here `Letter::n(65)` would return `Some(Letter::A)`.
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, Data, DeriveInput, Error, Fields, Ident};
+
+#[proc_macro_derive(N)]
+pub fn derive(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+
+    let variants = match input.data {
+        Data::Enum(data) => data.variants,
+        Data::Struct(_) | Data::Union(_) => panic!("input must be an enum"),
+    };
+
+    for variant in &variants {
+        match variant.fields {
+            Fields::Unit => {}
+            Fields::Named(_) | Fields::Unnamed(_) => {
+                let span = variant.ident.span();
+                let err = Error::new(span, "enumn: variant with data is not supported");
+                return err.to_compile_error().into();
+            }
+        }
+    }
+
+    // Parse repr attribute like #[repr(u16)].
+    let mut repr = None;
+    for attr in input.attrs {
+        if attr.path.is_ident("repr") {
+            if let Ok(name) = attr.parse_args::<Ident>() {
+                match name.to_string().as_str() {
+                    "u8" | "u16" | "u32" | "u64" | "u128" | "usize" | "i8" | "i16" | "i32"
+                    | "i64" | "i128" | "isize" => {
+                        repr = Some(quote!(#name));
+                    }
+                    _ => {}
+                }
+            }
+        }
+    }
+
+    let signature;
+    let value;
+    match repr {
+        Some(ref repr) => {
+            signature = quote! {
+                fn n(value: #repr)
+            };
+            value = quote!(value);
+        }
+        None => {
+            repr = Some(quote!(i64));
+            signature = quote! {
+                fn n<REPR: Into<i64>>(value: REPR)
+            };
+            value = quote! {
+                <REPR as Into<i64>>::into(value)
+            };
+        }
+    }
+
+    let ident = input.ident;
+    let declare_discriminants = variants.iter().map(|variant| {
+        let variant = &variant.ident;
+        quote! {
+            const #variant: #repr = #ident::#variant as #repr;
+        }
+    });
+    let match_discriminants = variants.iter().map(|variant| {
+        let variant = &variant.ident;
+        quote! {
+            discriminant::#variant => Some(#ident::#variant),
+        }
+    });
+
+    TokenStream::from(quote! {
+        impl #ident {
+            pub #signature -> Option<Self> {
+                struct discriminant;
+                #[allow(non_upper_case_globals)]
+                impl discriminant {
+                    #(#declare_discriminants)*
+                }
+                match #value {
+                    #(#match_discriminants)*
+                    _ => None,
+                }
+            }
+        }
+    })
+}