From ac3d8e35d4a4ca4311d938ac46af9bb649c0b8f2 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Tue, 23 Feb 2021 11:56:04 +0800
Subject: [PATCH] Add splitn, rsplit and rsplitn equivalents to strings.

---
 RELEASES.md                 |  1 +
 src/engine.rs               |  2 +-
 src/packages/string_more.rs | 59 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/RELEASES.md b/RELEASES.md
index 0e1c7177..15c54c99 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -29,6 +29,7 @@ Enhancements
 * Error position in `eval` statements is now wrapped in an `EvalAltResult::ErrorInFunctionCall`.
 * `Position` now implements `Add` and `AddAssign`.
 * `Scope` now implements `IntoIterator`.
+* Strings now have the `split_rev` method and variations of `split` with maximum number of segments.
 
 
 Version 0.19.12
diff --git a/src/engine.rs b/src/engine.rs
index ee54e8bd..0444e875 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -627,7 +627,7 @@ pub struct Limits {
 
 /// Context of a script evaluation process.
 #[derive(Debug)]
-pub struct EvalContext<'e, 'x, 'px: 'x, 'a, 's, 'm, 't, 'pt: 't> {
+pub struct EvalContext<'e, 'x, 'px, 'a, 's, 'm, 't, 'pt> {
     pub(crate) engine: &'e Engine,
     pub(crate) scope: &'x mut Scope<'px>,
     pub(crate) mods: &'a mut Imports,
diff --git a/src/packages/string_more.rs b/src/packages/string_more.rs
index 65032da2..427627fb 100644
--- a/src/packages/string_more.rs
+++ b/src/packages/string_more.rs
@@ -360,7 +360,8 @@ mod string_functions {
 
     #[cfg(not(feature = "no_index"))]
     pub mod arrays {
-        use crate::Array;
+        use crate::stdlib::vec;
+        use crate::{Array, ImmutableString};
 
         #[rhai_fn(name = "+")]
         pub fn append(string: &str, array: Array) -> String {
@@ -370,13 +371,69 @@ mod string_functions {
         pub fn prepend(array: &mut Array, string: &str) -> String {
             format!("{:?}{}", array, string)
         }
+        #[rhai_fn(name = "split")]
+        pub fn split_at(string: ImmutableString, start: INT) -> Array {
+            if start <= 0 {
+                vec!["".into(), string.into()]
+            } else {
+                let prefix: String = string.chars().take(start as usize).collect();
+                let prefix_len = prefix.len();
+                vec![prefix.into(), string[prefix_len..].into()]
+            }
+        }
         pub fn split(string: &str, delimiter: &str) -> Array {
             string.split(delimiter).map(Into::<Dynamic>::into).collect()
         }
         #[rhai_fn(name = "split")]
+        pub fn splitn(string: &str, delimiter: &str, segments: INT) -> Array {
+            let pieces: usize = if segments < 1 { 1 } else { segments as usize };
+            string
+                .splitn(pieces, delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
+        #[rhai_fn(name = "split")]
         pub fn split_char(string: &str, delimiter: char) -> Array {
             string.split(delimiter).map(Into::<Dynamic>::into).collect()
         }
+        #[rhai_fn(name = "split")]
+        pub fn splitn_char(string: &str, delimiter: char, segments: INT) -> Array {
+            let pieces: usize = if segments < 1 { 1 } else { segments as usize };
+            string
+                .splitn(pieces, delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
+        #[rhai_fn(name = "split_rev")]
+        pub fn rsplit(string: &str, delimiter: &str) -> Array {
+            string
+                .rsplit(delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
+        #[rhai_fn(name = "split_rev")]
+        pub fn rsplitn(string: &str, delimiter: &str, segments: INT) -> Array {
+            let pieces: usize = if segments < 1 { 1 } else { segments as usize };
+            string
+                .rsplitn(pieces, delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
+        #[rhai_fn(name = "split_rev")]
+        pub fn rsplit_char(string: &str, delimiter: char) -> Array {
+            string
+                .rsplit(delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
+        #[rhai_fn(name = "split_rev")]
+        pub fn rsplitn_char(string: &str, delimiter: char, segments: INT) -> Array {
+            let pieces: usize = if segments < 1 { 1 } else { segments as usize };
+            string
+                .rsplitn(pieces, delimiter)
+                .map(Into::<Dynamic>::into)
+                .collect()
+        }
     }
 
     #[cfg(not(feature = "no_object"))]