replace regex crate with fancy_regex (#14646)

# Description

We removed the regex crate long ago but there were a few instances where
we could not remove it because fancy-regex did not have a split/splitn,
and maybe other functions. Those functions now exist in the latest
fancy-regex crate so we can now remove it.
 
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->

# Tests + Formatting
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- `cargo fmt --all -- --check` to check standard code formatting (`cargo
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> from `nushell` you can also use the `toolkit` as follows
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crates/nu-command/Cargo.toml

@@ -76,7 +76,6 @@ quick-xml = { workspace = true }
 rand = { workspace = true, optional = true }
 getrandom = { workspace = true, optional = true }
 rayon = { workspace = true }
-regex = { workspace = true }
 roxmltree = { workspace = true }
 rusqlite = { workspace = true, features = ["bundled", "backup", "chrono"], optional = true }
 rmp = { workspace = true }

crates/nu-command/src/conversions/into/value.rs

@@ -1,7 +1,7 @@
 use crate::parse_date_from_string;
+use fancy_regex::{Regex, RegexBuilder};
 use nu_engine::command_prelude::*;
 use nu_protocol::PipelineIterator;
-use regex::{Regex, RegexBuilder};
 use std::collections::HashSet;
 use std::sync::LazyLock;
 
@@ -143,7 +143,7 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
     let val_str = val.coerce_str().unwrap_or_default();
 
     // step 2: bounce string up against regexes
-    if BOOLEAN_RE.is_match(&val_str) {
+    if BOOLEAN_RE.is_match(&val_str).unwrap_or(false) {
         let bval = val_str
             .parse::<bool>()
             .map_err(|_| ShellError::CantConvert {
@@ -156,12 +156,12 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
             })?;
 
         Ok(Value::bool(bval, span))
-    } else if FLOAT_RE.is_match(&val_str) {
+    } else if FLOAT_RE.is_match(&val_str).unwrap_or(false) {
         let fval = val_str
             .parse::<f64>()
             .map_err(|_| ShellError::CantConvert {
-                to_type: "string".to_string(),
-                from_type: "float".to_string(),
+                to_type: "float".to_string(),
+                from_type: "string".to_string(),
                 span,
                 help: Some(format!(
                     r#""{val_str}" does not represent a valid floating point value"#
@@ -169,12 +169,12 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
             })?;
 
         Ok(Value::float(fval, span))
-    } else if INTEGER_RE.is_match(&val_str) {
+    } else if INTEGER_RE.is_match(&val_str).unwrap_or(false) {
         let ival = val_str
             .parse::<i64>()
             .map_err(|_| ShellError::CantConvert {
-                to_type: "string".to_string(),
-                from_type: "int".to_string(),
+                to_type: "int".to_string(),
+                from_type: "string".to_string(),
                 span,
                 help: Some(format!(
                     r#""{val_str}" does not represent a valid integer value"#
@@ -186,15 +186,15 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
         } else {
             Ok(Value::int(ival, span))
         }
-    } else if INTEGER_WITH_DELIMS_RE.is_match(&val_str) {
+    } else if INTEGER_WITH_DELIMS_RE.is_match(&val_str).unwrap_or(false) {
         let mut val_str = val_str.into_owned();
         val_str.retain(|x| !['_', ','].contains(&x));
 
         let ival = val_str
             .parse::<i64>()
             .map_err(|_| ShellError::CantConvert {
-                to_type: "string".to_string(),
-                from_type: "int".to_string(),
+                to_type: "int".to_string(),
+                from_type: "string".to_string(),
                 span,
                 help: Some(format!(
                     r#""{val_str}" does not represent a valid integer value"#
@@ -206,7 +206,7 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
         } else {
             Ok(Value::int(ival, span))
         }
-    } else if DATETIME_DMY_RE.is_match(&val_str) {
+    } else if DATETIME_DMY_RE.is_match(&val_str).unwrap_or(false) {
         let dt = parse_date_from_string(&val_str, span).map_err(|_| ShellError::CantConvert {
             to_type: "date".to_string(),
             from_type: "string".to_string(),
@@ -217,7 +217,7 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
         })?;
 
         Ok(Value::date(dt, span))
-    } else if DATETIME_YMD_RE.is_match(&val_str) {
+    } else if DATETIME_YMD_RE.is_match(&val_str).unwrap_or(false) {
         let dt = parse_date_from_string(&val_str, span).map_err(|_| ShellError::CantConvert {
             to_type: "date".to_string(),
             from_type: "string".to_string(),
@@ -228,7 +228,7 @@ fn process_cell(val: Value, display_as_filesizes: bool, span: Span) -> Result<Va
         })?;
 
         Ok(Value::date(dt, span))
-    } else if DATETIME_YMDZ_RE.is_match(&val_str) {
+    } else if DATETIME_YMDZ_RE.is_match(&val_str).unwrap_or(false) {
         let dt = parse_date_from_string(&val_str, span).map_err(|_| ShellError::CantConvert {
             to_type: "date".to_string(),
             from_type: "string".to_string(),
@@ -372,118 +372,154 @@ mod test {
     #[test]
     fn test_float_parse() {
         // The regex should work on all these but nushell's float parser is more strict
-        assert!(FLOAT_RE.is_match("0.1"));
-        assert!(FLOAT_RE.is_match("3.0"));
-        assert!(FLOAT_RE.is_match("3.00001"));
-        assert!(FLOAT_RE.is_match("-9.9990e-003"));
-        assert!(FLOAT_RE.is_match("9.9990e+003"));
-        assert!(FLOAT_RE.is_match("9.9990E+003"));
-        assert!(FLOAT_RE.is_match("9.9990E+003"));
-        assert!(FLOAT_RE.is_match(".5"));
-        assert!(FLOAT_RE.is_match("2.5E-10"));
-        assert!(FLOAT_RE.is_match("2.5e10"));
-        assert!(FLOAT_RE.is_match("NaN"));
-        assert!(FLOAT_RE.is_match("-NaN"));
-        assert!(FLOAT_RE.is_match("-inf"));
-        assert!(FLOAT_RE.is_match("inf"));
-        assert!(FLOAT_RE.is_match("-7e-05"));
-        assert!(FLOAT_RE.is_match("7e-05"));
-        assert!(FLOAT_RE.is_match("+7e+05"));
+        assert!(FLOAT_RE.is_match("0.1").unwrap());
+        assert!(FLOAT_RE.is_match("3.0").unwrap());
+        assert!(FLOAT_RE.is_match("3.00001").unwrap());
+        assert!(FLOAT_RE.is_match("-9.9990e-003").unwrap());
+        assert!(FLOAT_RE.is_match("9.9990e+003").unwrap());
+        assert!(FLOAT_RE.is_match("9.9990E+003").unwrap());
+        assert!(FLOAT_RE.is_match("9.9990E+003").unwrap());
+        assert!(FLOAT_RE.is_match(".5").unwrap());
+        assert!(FLOAT_RE.is_match("2.5E-10").unwrap());
+        assert!(FLOAT_RE.is_match("2.5e10").unwrap());
+        assert!(FLOAT_RE.is_match("NaN").unwrap());
+        assert!(FLOAT_RE.is_match("-NaN").unwrap());
+        assert!(FLOAT_RE.is_match("-inf").unwrap());
+        assert!(FLOAT_RE.is_match("inf").unwrap());
+        assert!(FLOAT_RE.is_match("-7e-05").unwrap());
+        assert!(FLOAT_RE.is_match("7e-05").unwrap());
+        assert!(FLOAT_RE.is_match("+7e+05").unwrap());
     }
 
     #[test]
     fn test_int_parse() {
-        assert!(INTEGER_RE.is_match("0"));
-        assert!(INTEGER_RE.is_match("1"));
-        assert!(INTEGER_RE.is_match("10"));
-        assert!(INTEGER_RE.is_match("100"));
-        assert!(INTEGER_RE.is_match("1000"));
-        assert!(INTEGER_RE.is_match("10000"));
-        assert!(INTEGER_RE.is_match("100000"));
-        assert!(INTEGER_RE.is_match("1000000"));
-        assert!(INTEGER_RE.is_match("10000000"));
-        assert!(INTEGER_RE.is_match("100000000"));
-        assert!(INTEGER_RE.is_match("1000000000"));
-        assert!(INTEGER_RE.is_match("10000000000"));
-        assert!(INTEGER_RE.is_match("100000000000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000_000_000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("100,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("100,000,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000,000,000"));
-        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000,000,000"));
+        assert!(INTEGER_RE.is_match("0").unwrap());
+        assert!(INTEGER_RE.is_match("1").unwrap());
+        assert!(INTEGER_RE.is_match("10").unwrap());
+        assert!(INTEGER_RE.is_match("100").unwrap());
+        assert!(INTEGER_RE.is_match("1000").unwrap());
+        assert!(INTEGER_RE.is_match("10000").unwrap());
+        assert!(INTEGER_RE.is_match("100000").unwrap());
+        assert!(INTEGER_RE.is_match("1000000").unwrap());
+        assert!(INTEGER_RE.is_match("10000000").unwrap());
+        assert!(INTEGER_RE.is_match("100000000").unwrap());
+        assert!(INTEGER_RE.is_match("1000000000").unwrap());
+        assert!(INTEGER_RE.is_match("10000000000").unwrap());
+        assert!(INTEGER_RE.is_match("100000000000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1_000_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10_000_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("100_000_000_000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("100,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("100,000,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("1,000,000,000").unwrap());
+        assert!(INTEGER_WITH_DELIMS_RE.is_match("10,000,000,000").unwrap());
     }
 
     #[test]
     fn test_bool_parse() {
-        assert!(BOOLEAN_RE.is_match("true"));
-        assert!(BOOLEAN_RE.is_match("false"));
-        assert!(!BOOLEAN_RE.is_match("1"));
-        assert!(!BOOLEAN_RE.is_match("0"));
+        assert!(BOOLEAN_RE.is_match("true").unwrap());
+        assert!(BOOLEAN_RE.is_match("false").unwrap());
+        assert!(!BOOLEAN_RE.is_match("1").unwrap());
+        assert!(!BOOLEAN_RE.is_match("0").unwrap());
     }
 
     #[test]
     fn test_datetime_ymdz_pattern() {
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00Z"));
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789Z"));
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00+01:00"));
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789+01:00"));
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00-01:00"));
-        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789-01:00"));
-        assert!(DATETIME_YMDZ_RE.is_match("'2022-01-01T00:00:00Z'"));
+        assert!(DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00Z").unwrap());
+        assert!(DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789Z")
+            .unwrap());
+        assert!(DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00+01:00")
+            .unwrap());
+        assert!(DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789+01:00")
+            .unwrap());
+        assert!(DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00-01:00")
+            .unwrap());
+        assert!(DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789-01:00")
+            .unwrap());
+        assert!(DATETIME_YMDZ_RE.is_match("'2022-01-01T00:00:00Z'").unwrap());
 
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00."));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00+01"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00+01:0"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00+1:00"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789+01"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789+01:0"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789+1:00"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00-01"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00-01:0"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00-1:00"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789-01"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789-01:0"));
-        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.123456789-1:00"));
+        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00").unwrap());
+        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00.").unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00+01").unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00+01:0")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00+1:00")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789+01")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789+01:0")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789+1:00")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE.is_match("2022-01-01T00:00:00-01").unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00-01:0")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00-1:00")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789-01")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789-01:0")
+            .unwrap());
+        assert!(!DATETIME_YMDZ_RE
+            .is_match("2022-01-01T00:00:00.123456789-1:00")
+            .unwrap());
     }
 
     #[test]
     fn test_datetime_ymd_pattern() {
-        assert!(DATETIME_YMD_RE.is_match("2022-01-01"));
-        assert!(DATETIME_YMD_RE.is_match("2022/01/01"));
-        assert!(DATETIME_YMD_RE.is_match("2022-01-01T00:00:00"));
-        assert!(DATETIME_YMD_RE.is_match("2022-01-01T00:00:00.000000000"));
-        assert!(DATETIME_YMD_RE.is_match("'2022-01-01'"));
+        assert!(DATETIME_YMD_RE.is_match("2022-01-01").unwrap());
+        assert!(DATETIME_YMD_RE.is_match("2022/01/01").unwrap());
+        assert!(DATETIME_YMD_RE.is_match("2022-01-01T00:00:00").unwrap());
+        assert!(DATETIME_YMD_RE
+            .is_match("2022-01-01T00:00:00.000000000")
+            .unwrap());
+        assert!(DATETIME_YMD_RE.is_match("'2022-01-01'").unwrap());
 
         // The regex isn't this specific, but it would be nice if it were
-        // assert!(!DATETIME_YMD_RE.is_match("2022-13-01"));
-        // assert!(!DATETIME_YMD_RE.is_match("2022-01-32"));
-        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T24:00:00"));
-        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T00:60:00"));
-        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T00:00:60"));
-        assert!(!DATETIME_YMD_RE.is_match("2022-01-01T00:00:00.0000000000"));
+        // assert!(!DATETIME_YMD_RE.is_match("2022-13-01").unwrap());
+        // assert!(!DATETIME_YMD_RE.is_match("2022-01-32").unwrap());
+        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T24:00:00").unwrap());
+        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T00:60:00").unwrap());
+        // assert!(!DATETIME_YMD_RE.is_match("2022-01-01T00:00:60").unwrap());
+        assert!(!DATETIME_YMD_RE
+            .is_match("2022-01-01T00:00:00.0000000000")
+            .unwrap());
     }
 
     #[test]
     fn test_datetime_dmy_pattern() {
-        assert!(DATETIME_DMY_RE.is_match("31-12-2021"));
-        assert!(DATETIME_DMY_RE.is_match("01/01/2022"));
-        assert!(DATETIME_DMY_RE.is_match("15-06-2023 12:30"));
-        assert!(!DATETIME_DMY_RE.is_match("2022-13-01"));
-        assert!(!DATETIME_DMY_RE.is_match("2022-01-32"));
-        assert!(!DATETIME_DMY_RE.is_match("2022-01-01 24:00"));
+        assert!(DATETIME_DMY_RE.is_match("31-12-2021").unwrap());
+        assert!(DATETIME_DMY_RE.is_match("01/01/2022").unwrap());
+        assert!(DATETIME_DMY_RE.is_match("15-06-2023 12:30").unwrap());
+        assert!(!DATETIME_DMY_RE.is_match("2022-13-01").unwrap());
+        assert!(!DATETIME_DMY_RE.is_match("2022-01-32").unwrap());
+        assert!(!DATETIME_DMY_RE.is_match("2022-01-01 24:00").unwrap());
     }
 }

crates/nu-command/src/help/help_.rs

@@ -1,5 +1,5 @@
 use crate::help::{help_aliases, help_commands, help_modules};
-use fancy_regex::Regex;
+use fancy_regex::{escape, Regex};
 use nu_ansi_term::Style;
 use nu_engine::command_prelude::*;
 use nu_utils::IgnoreCaseExt;
@@ -193,7 +193,7 @@ pub fn highlight_search_string(
     string_style: &Style,
     highlight_style: &Style,
 ) -> Result<String, ShellError> {
-    let escaped_needle = regex::escape(needle);
+    let escaped_needle = escape(needle);
     let regex_string = format!("(?i){escaped_needle}");
     let regex = match Regex::new(&regex_string) {
         Ok(regex) => regex,

crates/nu-command/src/strings/split/column.rs

@@ -1,7 +1,6 @@
+use fancy_regex::{escape, Regex};
 use nu_engine::command_prelude::*;
 
-use regex::Regex;
-
 #[derive(Clone)]
 pub struct SubCommand;
 
@@ -182,7 +181,7 @@ fn split_column(
     let regex = if args.has_regex {
         Regex::new(&args.separator.item)
     } else {
-        let escaped = regex::escape(&args.separator.item);
+        let escaped = escape(&args.separator.item);
         Regex::new(&escaped)
     }
     .map_err(|e| ShellError::GenericError {
@@ -220,10 +219,12 @@ fn split_column_helper(
         let split_result: Vec<_> = match max_split {
             Some(max_split) => separator
                 .splitn(&s, max_split)
+                .filter_map(|x| x.ok())
                 .filter(|x| !(collapse_empty && x.is_empty()))
                 .collect(),
             None => separator
                 .split(&s)
+                .filter_map(|x| x.ok())
                 .filter(|x| !(collapse_empty && x.is_empty()))
                 .collect(),
         };

crates/nu-command/src/strings/split/list.rs

@@ -1,7 +1,6 @@
+use fancy_regex::Regex;
 use nu_engine::command_prelude::*;
 
-use regex::Regex;
-
 #[derive(Clone)]
 pub struct SubCommand;
 
@@ -193,7 +192,7 @@ impl Matcher {
         Ok(match self {
             Matcher::Regex(regex) => {
                 if let Ok(rhs_str) = rhs.coerce_str() {
-                    regex.is_match(&rhs_str)
+                    regex.is_match(&rhs_str).unwrap_or(false)
                 } else {
                     false
                 }

crates/nu-command/src/strings/split/row.rs

@@ -1,7 +1,6 @@
+use fancy_regex::{escape, Regex};
 use nu_engine::command_prelude::*;
 
-use regex::Regex;
-
 #[derive(Clone)]
 pub struct SubCommand;
 
@@ -158,7 +157,7 @@ fn split_row(
     let regex = if args.has_regex {
         Regex::new(&args.separator.item)
     } else {
-        let escaped = regex::escape(&args.separator.item);
+        let escaped = escape(&args.separator.item);
         Regex::new(&escaped)
     }
     .map_err(|e| ShellError::GenericError {
@@ -187,11 +186,35 @@ fn split_row_helper(v: &Value, regex: &Regex, max_split: Option<usize>, name: Sp
                 match max_split {
                     Some(max_split) => regex
                         .splitn(&s, max_split)
-                        .map(|x: &str| Value::string(x, v_span))
+                        .map(|x| match x {
+                            Ok(val) => Value::string(val, v_span),
+                            Err(err) => Value::error(
+                                ShellError::GenericError {
+                                    error: "Error with regular expression".into(),
+                                    msg: err.to_string(),
+                                    span: Some(v_span),
+                                    help: None,
+                                    inner: vec![],
+                                },
+                                v_span,
+                            ),
+                        })
                         .collect(),
                     None => regex
                         .split(&s)
-                        .map(|x: &str| Value::string(x, v_span))
+                        .map(|x| match x {
+                            Ok(val) => Value::string(val, v_span),
+                            Err(err) => Value::error(
+                                ShellError::GenericError {
+                                    error: "Error with regular expression".into(),
+                                    msg: err.to_string(),
+                                    span: Some(v_span),
+                                    help: None,
+                                    inner: vec![],
+                                },
+                                v_span,
+                            ),
+                        })
                         .collect(),
                 }
             } else {