Import 'predicates-core' crateupstream

Request Document: go/android-rust-importing-crates
For CL Reviewers: go/android3p#cl-review
For Build Team: go/ab-third-party-imports
Bug: 310599818

Change-Id: I662dcdb358a1e058a7c2339e5fb9e4b54d2f7650

14 files changed, 660 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..07e7fdd
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,6 @@
+{
+  "git": {
+    "sha1": "7b72b706abbf1509fc74ee18e363d2bc7e8520a6"
+  },
+  "path_in_vcs": "crates/core"
+}
\ No newline at end of file
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..2a94e01
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,18 @@
+// This file is generated by cargo_embargo.
+// Do not modify this file as changes will be overridden on upgrade.
+
+rust_library {
+    name: "libpredicates_core",
+    host_supported: true,
+    crate_name: "predicates_core",
+    cargo_env_compat: true,
+    cargo_pkg_version: "1.0.6",
+    srcs: ["src/lib.rs"],
+    edition: "2021",
+    apex_available: [
+        "//apex_available:platform",
+        "//apex_available:anyapex",
+    ],
+    product_available: true,
+    vendor_available: true,
+}
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..a1de8f1
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,78 @@
+# 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 = "2021"
+rust-version = "1.64.0"
+name = "predicates-core"
+version = "1.0.6"
+authors = ["Nick Stevens <nick@bitcurry.com>"]
+include = [
+    "build.rs",
+    "src/**/*",
+    "Cargo.toml",
+    "LICENSE*",
+    "README.md",
+    "benches/**/*",
+    "examples/**/*",
+]
+description = "An API for boolean-valued predicate functions."
+homepage = "https://github.com/assert-rs/predicates-rs/tree/master/crates/core"
+documentation = "https://docs.rs/predicates-core"
+readme = "README.md"
+keywords = [
+    "predicate",
+    "boolean",
+    "combinatorial",
+    "match",
+    "logic",
+]
+categories = [
+    "data-structures",
+    "rust-patterns",
+]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/assert-rs/predicates-rs/tree/master/crates/core"
+
+[[package.metadata.release.pre-release-replacements]]
+file = "CHANGELOG.md"
+search = "Unreleased"
+replace = "{{version}}"
+min = 1
+
+[[package.metadata.release.pre-release-replacements]]
+file = "CHANGELOG.md"
+search = '\.\.\.HEAD'
+replace = "...{{tag_name}}"
+exactly = 1
+
+[[package.metadata.release.pre-release-replacements]]
+file = "CHANGELOG.md"
+search = "ReleaseDate"
+replace = "{{date}}"
+min = 1
+
+[[package.metadata.release.pre-release-replacements]]
+file = "CHANGELOG.md"
+search = "<!-- next-header -->"
+replace = """
+<!-- next-header -->
+## [Unreleased] - ReleaseDate
+"""
+exactly = 1
+
+[[package.metadata.release.pre-release-replacements]]
+file = "CHANGELOG.md"
+search = "<!-- next-url -->"
+replace = """
+<!-- next-url -->
+[Unreleased]: https://github.com/assert-rs/predicates-rs/compare/{{tag_name}}...HEAD"""
+exactly = 1
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..d9a10c0
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,176 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+   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
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+   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
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+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
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+   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,
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+   9. Accepting Warranty or Additional Liability. While redistributing
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+   END OF TERMS AND CONDITIONS
diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..51e7743
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,22 @@
+MIT License
+
+Copyright (c) 2017 Nick Stevens
+
+
+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, publish, distribute, sublicense, and/or sell
+copies of 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 CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..cd32702
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,20 @@
+name: "predicates-core"
+description: "An API for boolean-valued predicate functions."
+third_party {
+  identifier {
+    type: "crates.io"
+    value: "https://crates.io/crates/predicates-core"
+  }
+  identifier {
+    type: "Archive"
+    value: "https://static.crates.io/crates/predicates-core/predicates-core-1.0.6.crate"
+  }
+  version: "1.0.6"
+  # Dual-licensed, using the least restrictive per go/thirdpartylicenses#same.
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2023
+    month: 11
+    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..48bea6e
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,2 @@
+# Bug component: 688011
+include platform/prebuilts/rust:main:/OWNERS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..57ec3ac
--- /dev/null
+++ b/README.md
@@ -0,0 +1,25 @@
+# predicates-core
+
+> Traits for **boolean-valued predicate functions** in Rust.
+
+[![Build Status](https://dev.azure.com/assert-rs/assert-rs/_apis/build/status/predicates-rs?branchName=master)](https://dev.azure.com/assert-rs/assert-rs/_build/latest?definitionId=1&branchName=master)
+[![Documentation](https://img.shields.io/badge/docs-master-blue.svg)](https://docs.rs/predicates-core)
+![License](https://img.shields.io/crates/l/predicates-core.svg)
+[![Crates.io](https://img.shields.io/crates/v/predicates-core.svg?maxAge=2592000)](https://crates.io/crates/predicates-core)
+
+[Changelog](https://github.com/assert-rs/predicates-rs/blob/master/crates/core/CHANGELOG.md)
+
+
+## License
+
+`predicates-core` is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0).
+
+See LICENSE-APACHE, and LICENSE-MIT for details.
+
+
+## Credits
+
+Big thanks to [futures-rs](https://github.com/alexcrichton/futures-rs), whose
+slick API design informed a lot of decisions made on the API design of this
+library.
diff --git a/cargo_embargo.json b/cargo_embargo.json
new file mode 100644
index 0000000..9a0a579
--- /dev/null
+++ b/cargo_embargo.json
@@ -0,0 +1,3 @@
+{
+  "tests": true
+}
diff --git a/src/core.rs b/src/core.rs
new file mode 100644
index 0000000..b5aaa7b
--- /dev/null
+++ b/src/core.rs
@@ -0,0 +1,32 @@
+// Copyright (c) 2018 The predicates-rs Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use crate::reflection;
+
+/// Trait for generically evaluating a type against a dynamically created
+/// predicate function.
+///
+/// The exact meaning of `eval` depends on the situation, but will usually
+/// mean that the evaluated item is in some sort of pre-defined set.  This is
+/// different from `Ord` and `Eq` in that an `item` will almost never be the
+/// same type as the implementing `Predicate` type.
+pub trait Predicate<Item: ?Sized>: reflection::PredicateReflection {
+    /// Execute this `Predicate` against `variable`, returning the resulting
+    /// boolean.
+    fn eval(&self, variable: &Item) -> bool;
+
+    /// Find a case that proves this predicate as `expected` when run against `variable`.
+    fn find_case<'a>(&'a self, expected: bool, variable: &Item) -> Option<reflection::Case<'a>> {
+        let actual = self.eval(variable);
+        if expected == actual {
+            Some(reflection::Case::new(None, actual))
+        } else {
+            None
+        }
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..e0c9ace
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,25 @@
+// Copyright (c) 2018 The predicates-rs Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/license/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Composable first-order predicate trait.
+//!
+//! This library implements an interface to "predicates" - boolean-valued
+//! functions of one argument. This allows combinatorial logic to be created and
+//! assembled at runtime and then used one or more times for evaluating values.
+//! This sort of object is really useful when creating filters and checks that
+//! can be changed at runtime with user interaction - it allows a clean
+//! separation of concerns where the configuration code can be used to build up
+//! a predicate, and then that predicate can be given to the code that does the
+//! actual filtering without the filtering code knowing anything about user
+//! configuration. See the examples for how this can work.
+
+#![warn(missing_docs, missing_debug_implementations)]
+
+mod core;
+pub use crate::core::*;
+pub mod reflection;
diff --git a/src/reflection.rs b/src/reflection.rs
new file mode 100644
index 0000000..120d1bd
--- /dev/null
+++ b/src/reflection.rs
@@ -0,0 +1,252 @@
+// Copyright (c) 2018 The predicates-rs Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Introspect into the state of a `Predicate`.
+
+use std::borrow;
+use std::fmt;
+use std::slice;
+
+/// Introspect the state of a `Predicate`.
+pub trait PredicateReflection: fmt::Display {
+    /// Parameters of the current `Predicate`.
+    fn parameters<'a>(&'a self) -> Box<dyn Iterator<Item = Parameter<'a>> + 'a> {
+        let params = vec![];
+        Box::new(params.into_iter())
+    }
+
+    /// Nested `Predicate`s of the current `Predicate`.
+    fn children<'a>(&'a self) -> Box<dyn Iterator<Item = Child<'a>> + 'a> {
+        let params = vec![];
+        Box::new(params.into_iter())
+    }
+}
+
+/// A view of a `Predicate` parameter, provided by reflection.
+///
+/// ```rust
+/// use predicates_core;
+///
+/// let param = predicates_core::reflection::Parameter::new("key", &10);
+/// println!("{}", param);
+/// ```
+pub struct Parameter<'a>(&'a str, &'a dyn fmt::Display);
+
+impl<'a> Parameter<'a> {
+    /// Create a new `Parameter`.
+    pub fn new(key: &'a str, value: &'a dyn fmt::Display) -> Self {
+        Self(key, value)
+    }
+
+    /// Access the `Parameter` name.
+    pub fn name(&self) -> &str {
+        self.0
+    }
+
+    /// Access the `Parameter` value.
+    pub fn value(&self) -> &dyn fmt::Display {
+        self.1
+    }
+}
+
+impl<'a> fmt::Display for Parameter<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}: {}", self.0, self.1)
+    }
+}
+
+impl<'a> fmt::Debug for Parameter<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "({:?}, {})", self.0, self.1)
+    }
+}
+
+/// A view of a `Predicate` child, provided by reflection.
+pub struct Child<'a>(&'a str, &'a dyn PredicateReflection);
+
+impl<'a> Child<'a> {
+    /// Create a new `Predicate` child.
+    pub fn new(key: &'a str, value: &'a dyn PredicateReflection) -> Self {
+        Self(key, value)
+    }
+
+    /// Access the `Child`'s name.
+    pub fn name(&self) -> &str {
+        self.0
+    }
+
+    /// Access the `Child` `Predicate`.
+    pub fn value(&self) -> &dyn PredicateReflection {
+        self.1
+    }
+}
+
+impl<'a> fmt::Display for Child<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}: {}", self.0, self.1)
+    }
+}
+
+impl<'a> fmt::Debug for Child<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "({:?}, {})", self.0, self.1)
+    }
+}
+
+/// A descriptive explanation for why a predicate failed.
+pub struct Case<'a> {
+    predicate: Option<&'a dyn PredicateReflection>,
+    result: bool,
+    products: Vec<Product>,
+    children: Vec<Case<'a>>,
+}
+
+impl<'a> Case<'a> {
+    /// Create a new `Case` describing the result of a `Predicate`.
+    pub fn new(predicate: Option<&'a dyn PredicateReflection>, result: bool) -> Self {
+        Self {
+            predicate,
+            result,
+            products: Default::default(),
+            children: Default::default(),
+        }
+    }
+
+    /// Add an additional by product to a `Case`.
+    pub fn add_product(mut self, product: Product) -> Self {
+        self.products.push(product);
+        self
+    }
+
+    /// Add an additional by product to a `Case`.
+    pub fn add_child(mut self, child: Case<'a>) -> Self {
+        self.children.push(child);
+        self
+    }
+
+    /// The `Predicate` that produced this case.
+    pub fn predicate(&self) -> Option<&dyn PredicateReflection> {
+        self.predicate
+    }
+
+    /// The result of this case.
+    pub fn result(&self) -> bool {
+        self.result
+    }
+
+    /// Access the by-products from determining this case.
+    pub fn products(&self) -> CaseProducts<'_> {
+        CaseProducts(self.products.iter())
+    }
+
+    /// Access the sub-cases.
+    pub fn children(&self) -> CaseChildren<'_> {
+        CaseChildren(self.children.iter())
+    }
+}
+
+impl<'a> fmt::Debug for Case<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let predicate = if let Some(ref predicate) = self.predicate {
+            format!("Some({})", predicate)
+        } else {
+            "None".to_owned()
+        };
+        f.debug_struct("Case")
+            .field("predicate", &predicate)
+            .field("result", &self.result)
+            .field("products", &self.products)
+            .field("children", &self.children)
+            .finish()
+    }
+}
+
+/// Iterator over a `Case`s by-products.
+#[derive(Debug, Clone)]
+pub struct CaseProducts<'a>(slice::Iter<'a, Product>);
+
+impl<'a> Iterator for CaseProducts<'a> {
+    type Item = &'a Product;
+
+    fn next(&mut self) -> Option<&'a Product> {
+        self.0.next()
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint()
+    }
+
+    fn count(self) -> usize {
+        self.0.count()
+    }
+}
+
+/// Iterator over a `Case`s sub-cases.
+#[derive(Debug, Clone)]
+pub struct CaseChildren<'a>(slice::Iter<'a, Case<'a>>);
+
+impl<'a> Iterator for CaseChildren<'a> {
+    type Item = &'a Case<'a>;
+
+    fn next(&mut self) -> Option<&'a Case<'a>> {
+        self.0.next()
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint()
+    }
+
+    fn count(self) -> usize {
+        self.0.count()
+    }
+}
+
+/// A by-product of a predicate evaluation.
+///
+/// ```rust
+/// use predicates_core;
+///
+/// let product = predicates_core::reflection::Product::new("key", "value");
+/// println!("{}", product);
+/// let product = predicates_core::reflection::Product::new(format!("key-{}", 5), 30);
+/// println!("{}", product);
+/// ```
+pub struct Product(borrow::Cow<'static, str>, Box<dyn fmt::Display>);
+
+impl Product {
+    /// Create a new `Product`.
+    pub fn new<S, D>(key: S, value: D) -> Self
+    where
+        S: Into<borrow::Cow<'static, str>>,
+        D: fmt::Display + 'static,
+    {
+        Self(key.into(), Box::new(value))
+    }
+
+    /// Access the `Product` name.
+    pub fn name(&self) -> &str {
+        self.0.as_ref()
+    }
+
+    /// Access the `Product` value.
+    pub fn value(&self) -> &dyn fmt::Display {
+        &self.1
+    }
+}
+
+impl fmt::Display for Product {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}: {}", self.0, self.1)
+    }
+}
+
+impl fmt::Debug for Product {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "({:?}, {})", self.0, self.1)
+    }
+}