1 files changed, 186 insertions, 0 deletions
diff --git a/third_party/rust/intl_pluralrules/src/operands.rs b/third_party/rust/intl_pluralrules/src/operands.rs
new file mode 100644
index 0000000000..102ae8742e
--- /dev/null
+++ b/third_party/rust/intl_pluralrules/src/operands.rs
@@ -0,0 +1,186 @@
+//! Plural operands in compliance with [CLDR Plural Rules](https://unicode.org/reports/tr35/tr35-numbers.html#Language_Plural_Rules).
+//!
+//! See [full operands description](https://unicode.org/reports/tr35/tr35-numbers.html#Operands).
+//!
+//! # Examples
+//!
+//! From int
+//!
+//! ```
+//! use std::convert::TryFrom;
+//! use intl_pluralrules::operands::*;
+//! assert_eq!(Ok(PluralOperands {
+//!    n: 2_f64,
+//!    i: 2,
+//!    v: 0,
+//!    w: 0,
+//!    f: 0,
+//!    t: 0,
+//! }), PluralOperands::try_from(2))
+//! ```
+//!
+//! From float
+//!
+//! ```
+//! use std::convert::TryFrom;
+//! use intl_pluralrules::operands::*;
+//! assert_eq!(Ok(PluralOperands {
+//!    n: 1234.567_f64,
+//!    i: 1234,
+//!    v: 3,
+//!    w: 3,
+//!    f: 567,
+//!    t: 567,
+//! }), PluralOperands::try_from("-1234.567"))
+//! ```
+//!
+//! From &str
+//!
+//! ```
+//! use std::convert::TryFrom;
+//! use intl_pluralrules::operands::*;
+//! assert_eq!(Ok(PluralOperands {
+//!    n: 123.45_f64,
+//!    i: 123,
+//!    v: 2,
+//!    w: 2,
+//!    f: 45,
+//!    t: 45,
+//! }), PluralOperands::try_from(123.45))
+//! ```
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::cast_lossless))]
+use std::convert::TryFrom;
+use std::isize;
+use std::str::FromStr;
+
+/// A full plural operands representation of a number. See [CLDR Plural Rules](https://unicode.org/reports/tr35/tr35-numbers.html#Language_Plural_Rules) for complete operands description.
+#[derive(Debug, PartialEq)]
+pub struct PluralOperands {
+    /// Absolute value of input
+    pub n: f64,
+    /// Integer value of input
+    pub i: u64,
+    /// Number of visible fraction digits with trailing zeros
+    pub v: usize,
+    /// Number of visible fraction digits without trailing zeros
+    pub w: usize,
+    /// Visible fraction digits with trailing zeros
+    pub f: u64,
+    /// Visible fraction digits without trailing zeros
+    pub t: u64,
+}
+
+impl<'a> TryFrom<&'a str> for PluralOperands {
+    type Error = &'static str;
+
+    fn try_from(input: &'a str) -> Result<Self, Self::Error> {
+        let abs_str = if input.starts_with('-') {
+            &input[1..]
+        } else {
+            &input
+        };
+
+        let absolute_value = f64::from_str(&abs_str).map_err(|_| "Incorrect number passed!")?;
+
+        let integer_digits;
+        let num_fraction_digits0;
+        let num_fraction_digits;
+        let fraction_digits0;
+        let fraction_digits;
+
+        if let Some(dec_pos) = abs_str.find('.') {
+            let int_str = &abs_str[..dec_pos];
+            let dec_str = &abs_str[(dec_pos + 1)..];
+
+            integer_digits =
+                u64::from_str(&int_str).map_err(|_| "Could not convert string to integer!")?;
+
+            let backtrace = dec_str.trim_end_matches('0');
+
+            num_fraction_digits0 = dec_str.len() as usize;
+            num_fraction_digits = backtrace.len() as usize;
+            fraction_digits0 =
+                u64::from_str(dec_str).map_err(|_| "Could not convert string to integer!")?;
+            fraction_digits = u64::from_str(backtrace).unwrap_or(0);
+        } else {
+            integer_digits = absolute_value as u64;
+            num_fraction_digits0 = 0;
+            num_fraction_digits = 0;
+            fraction_digits0 = 0;
+            fraction_digits = 0;
+        }
+
+        Ok(PluralOperands {
+            n: absolute_value,
+            i: integer_digits,
+            v: num_fraction_digits0,
+            w: num_fraction_digits,
+            f: fraction_digits0,
+            t: fraction_digits,
+        })
+    }
+}
+
+macro_rules! impl_integer_type {
+    ($ty:ident) => {
+        impl From<$ty> for PluralOperands {
+            fn from(input: $ty) -> Self {
+                // XXXManishearth converting from u32 or u64 to isize may wrap
+                PluralOperands {
+                    n: input as f64,
+                    i: input as u64,
+                    v: 0,
+                    w: 0,
+                    f: 0,
+                    t: 0,
+                }
+            }
+        }
+    };
+    ($($ty:ident)+) => {
+        $(impl_integer_type!($ty);)+
+    };
+}
+
+macro_rules! impl_signed_integer_type {
+    ($ty:ident) => {
+        impl TryFrom<$ty> for PluralOperands {
+            type Error = &'static str;
+            fn try_from(input: $ty) -> Result<Self, Self::Error> {
+                // XXXManishearth converting from i64 to isize may wrap
+                let x = (input as isize).checked_abs().ok_or("Number too big")?;
+                Ok(PluralOperands {
+                    n: x as f64,
+                    i: x as u64,
+                    v: 0,
+                    w: 0,
+                    f: 0,
+                    t: 0,
+                })
+            }
+        }
+    };
+    ($($ty:ident)+) => {
+        $(impl_signed_integer_type!($ty);)+
+    };
+}
+
+macro_rules! impl_convert_type {
+    ($ty:ident) => {
+        impl TryFrom<$ty> for PluralOperands {
+            type Error = &'static str;
+            fn try_from(input: $ty) -> Result<Self, Self::Error> {
+                let as_str: &str = &input.to_string();
+                PluralOperands::try_from(as_str)
+            }
+        }
+    };
+    ($($ty:ident)+) => {
+        $(impl_convert_type!($ty);)+
+    };
+}
+
+impl_integer_type!(u8 u16 u32 u64 usize);
+impl_signed_integer_type!(i8 i16 i32 i64 isize);
+// XXXManishearth we can likely have dedicated float impls here
+impl_convert_type!(f32 f64 String);