2 files changed, 165 insertions, 0 deletions
diff --git a/helix-core/src/lib.rs b/helix-core/src/lib.rs
index 4ae044cc..92a59f31 100644
--- a/helix-core/src/lib.rs
+++ b/helix-core/src/lib.rs
@@ -17,6 +17,7 @@ mod position;
 pub mod register;
 pub mod search;
 pub mod selection;
+pub mod shellwords;
 mod state;
 pub mod surround;
 pub mod syntax;
diff --git a/helix-core/src/shellwords.rs b/helix-core/src/shellwords.rs
new file mode 100644
index 00000000..13f6f3e9
--- /dev/null
+++ b/helix-core/src/shellwords.rs
@@ -0,0 +1,164 @@
+use std::borrow::Cow;
+
+/// Get the vec of escaped / quoted / doublequoted filenames from the input str
+pub fn shellwords(input: &str) -> Vec<Cow<'_, str>> {
+    enum State {
+        Normal,
+        NormalEscaped,
+        Quoted,
+        QuoteEscaped,
+        Dquoted,
+        DquoteEscaped,
+    }
+
+    use State::*;
+
+    let mut state = Normal;
+    let mut args: Vec<Cow<str>> = Vec::new();
+    let mut escaped = String::with_capacity(input.len());
+
+    let mut start = 0;
+    let mut end = 0;
+
+    for (i, c) in input.char_indices() {
+        state = match state {
+            Normal => match c {
+                '\\' => {
+                    escaped.push_str(&input[start..i]);
+                    start = i + 1;
+                    NormalEscaped
+                }
+                '"' => {
+                    end = i;
+                    Dquoted
+                }
+                '\'' => {
+                    end = i;
+                    Quoted
+                }
+                c if c.is_ascii_whitespace() => {
+                    end = i;
+                    Normal
+                }
+                _ => Normal,
+            },
+            NormalEscaped => Normal,
+            Quoted => match c {
+                '\\' => {
+                    escaped.push_str(&input[start..i]);
+                    start = i + 1;
+                    QuoteEscaped
+                }
+                '\'' => {
+                    end = i;
+                    Normal
+                }
+                _ => Quoted,
+            },
+            QuoteEscaped => Quoted,
+            Dquoted => match c {
+                '\\' => {
+                    escaped.push_str(&input[start..i]);
+                    start = i + 1;
+                    DquoteEscaped
+                }
+                '"' => {
+                    end = i;
+                    Normal
+                }
+                _ => Dquoted,
+            },
+            DquoteEscaped => Dquoted,
+        };
+
+        if i >= input.len() - 1 && end == 0 {
+            end = i + 1;
+        }
+
+        if end > 0 {
+            let esc_trim = escaped.trim();
+            let inp = &input[start..end];
+
+            if !(esc_trim.is_empty() && inp.trim().is_empty()) {
+                if esc_trim.is_empty() {
+                    args.push(inp.into());
+                } else {
+                    args.push([escaped, inp.into()].concat().into());
+                    escaped = "".to_string();
+                }
+            }
+            start = i + 1;
+            end = 0;
+        }
+    }
+    args
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_normal() {
+        let input = r#":o single_word twó wörds \three\ \"with\ escaping\\"#;
+        let result = shellwords(input);
+        let expected = vec![
+            Cow::from(":o"),
+            Cow::from("single_word"),
+            Cow::from("twó"),
+            Cow::from("wörds"),
+            Cow::from(r#"three "with escaping\"#),
+        ];
+        // TODO test is_owned and is_borrowed, once they get stabilized.
+        assert_eq!(expected, result);
+    }
+
+    #[test]
+    fn test_quoted() {
+        let quoted =
+            r#":o 'single_word' 'twó wörds' '' ' ''\three\' \"with\ escaping\\' 'quote incomplete"#;
+        let result = shellwords(quoted);
+        let expected = vec![
+            Cow::from(":o"),
+            Cow::from("single_word"),
+            Cow::from("twó wörds"),
+            Cow::from(r#"three' "with escaping\"#),
+            Cow::from("quote incomplete"),
+        ];
+        assert_eq!(expected, result);
+    }
+
+    #[test]
+    fn test_dquoted() {
+        let dquoted = r#":o "single_word" "twó wörds" "" "  ""\three\' \"with\ escaping\\" "dquote incomplete"#;
+        let result = shellwords(dquoted);
+        let expected = vec![
+            Cow::from(":o"),
+            Cow::from("single_word"),
+            Cow::from("twó wörds"),
+            Cow::from(r#"three' "with escaping\"#),
+            Cow::from("dquote incomplete"),
+        ];
+        assert_eq!(expected, result);
+    }
+
+    #[test]
+    fn test_mixed() {
+        let dquoted = r#":o single_word 'twó wörds' "\three\' \"with\ escaping\\""no space before"'and after' $#%^@ "%^&(%^" ')(*&^%''a\\\\\b' '"#;
+        let result = shellwords(dquoted);
+        let expected = vec![
+            Cow::from(":o"),
+            Cow::from("single_word"),
+            Cow::from("twó wörds"),
+            Cow::from("three' \"with escaping\\"),
+            Cow::from("no space before"),
+            Cow::from("and after"),
+            Cow::from("$#%^@"),
+            Cow::from("%^&(%^"),
+            Cow::from(")(*&^%"),
+            Cow::from(r#"a\\b"#),
+            //last ' just changes to quoted but since we dont have anything after it, it should be ignored
+        ];
+        assert_eq!(expected, result);
+    }
+}