smarter match finding

.vscode/launch.json

@@ -0,0 +1,36 @@
+{
+	// Use IntelliSense to learn about possible attributes.
+	// Hover to view descriptions of existing attributes.
+	// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+	"version": "0.2.0",
+	"configurations": [
+		{
+			"type": "lldb",
+			"request": "launch",
+			"name": "Debug executable 'eyes'",
+			"cargo": {
+				"args": ["build", "--bin=eyes", "--package=eyes"],
+				"filter": {
+					"name": "eyes",
+					"kind": "bin"
+				}
+			},
+			"args": [],
+			"cwd": "${workspaceFolder}"
+		},
+		{
+			"type": "lldb",
+			"request": "launch",
+			"name": "Debug unit tests in executable 'eyes'",
+			"cargo": {
+				"args": ["test", "--no-run", "--bin=eyes", "--package=eyes"],
+				"filter": {
+					"name": "eyes",
+					"kind": "bin"
+				}
+			},
+			"args": [],
+			"cwd": "${workspaceFolder}"
+		}
+	]
+}

Cargo.toml

@@ -2,5 +2,6 @@
 name = "eyes"
 version = "0.1.0"
 edition = "2018"
+license-file="LICENSE.txt"
 
 [dependencies]

src/lib.rs

@@ -1,30 +1,42 @@
 pub struct Parser<'a> {
-    _input: &'a str,
-    _pattern: &'a str,
     captures: Vec<&'a str>,
 }
 
 impl<'a> Parser<'a> {
-    pub fn new(input: &'a str, pattern: &'a str) -> Self {
-        let splits = pattern
+    pub fn new(input: &'a str, template: &'a str) -> Self {
+        let patterns = template
             .split("{}")
             .filter(|pat| pat != &"")
             .collect::<Vec<_>>();
         let mut captures = vec![input];
 
-        for pat in splits {
-            captures = captures
-                .iter()
-                .map(|sub| sub.split(pat))
-                .flatten()
-                .collect();
+        for (i, pat) in patterns.iter().enumerate() {
+            let last = captures.pop().unwrap();
+            let (mut left, mut right) = last.split_once(pat).unwrap();
+
+            // if the right side of the split doesn't contain the pattern,
+            // we don't have to check if we can expand the match
+            if right.contains(pat) {
+                let mut pattern_index = right.find(pat).unwrap() + left.len();
+                let next_pattern_index = right.find(patterns[i + 1]).unwrap() + left.len();
+
+                while next_pattern_index > pattern_index {
+                    let (left_side, _) = input.split_at(pattern_index + 1);
+                    left = left_side;
+                    let (_, right_side) = input.split_at(pattern_index + 1 + pat.len());
+                    right = right_side;
+
+                    pattern_index = right.find(pat).unwrap_or(input.len()) + left.len();
+                }
+            }
+
+            if !left.is_empty() {
+                captures.push(left);
+            }
+            captures.push(right);
         }
 
-        Self {
-            _input: input,
-            _pattern: pattern,
-            captures: captures[1..].to_vec(),
-        }
+        Self { captures }
     }
 
     pub fn captures(&self) -> Vec<&'a str> {
@@ -36,15 +48,11 @@ impl<'a> Parser<'a> {
 macro_rules! parse {
     ($input: expr, $pattern: tt, $($type:ty),*) => {
         {
-            let mut parser = eyes::Parser::new($input, $pattern);
-            let mut captures = parser.captures();
-            captures.reverse();
+            let parser = $crate::Parser::new($input, $pattern);
+            let captures = parser.captures();
+            let mut iter = captures.iter();
 
-            (
-            $({
-                    captures.pop().unwrap().parse::<$type>().unwrap()
-            },)*
-            )
+            ($(iter.next().unwrap().parse::<$type>().unwrap()),*)
         }
     };
 }
@@ -53,15 +61,56 @@ macro_rules! parse {
 macro_rules! try_parse {
     ($input: expr, $pattern: tt, $($type:ty),*) => {
         {
-            let mut parser = eyes::Parser::new($input, $pattern);
-            let mut captures = parser.captures();
-            captures.reverse();
+            let parser = $crate::Parser::new($input, $pattern);
+            let captures = parser.captures();
+            let mut iter = captures.iter();
 
-            (
-            $({
-                    captures.pop().unwrap().parse::<$type>()
-            },)*
-            )
+            ($(iter.next().unwrap().parse::<$type>()),*)
         }
     };
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn simple_test() {
+        // Test where the patterns in the template are all different
+        let input = "#lol @ 338,7643: 20.2x24.5";
+        let template = "#{} @ {},{}: {}x{}";
+
+        println!("input: '{}'", input);
+        println!("pattern: '{}'", template);
+
+        let (id, x, y, w, h) = parse!(input, template, String, isize, isize, f64, f64);
+
+        println!("id: {:?}", id);
+        println!("x: {:?}", x);
+        println!("y: {:?}", y);
+        println!("w: {:?}", w);
+        println!("h: {:?}", h);
+
+        assert_eq!((id.as_str(), x, y, w, h), ("lol", 338, 7643, 20.2, 24.5));
+    }
+
+    #[test]
+    fn tries_to_expand_correctly() {
+        let input = "turn off 660,55 through 986,197";
+        let template = "{} {},{} through {},{}";
+
+        println!("input: '{}'", input);
+        println!("pattern: '{}'", template);
+
+        let (op, x1, y1, x2, y2) = try_parse!(input, template, String, usize, usize, usize, usize);
+
+        println!("op: {:?}", op);
+        println!("p1: {:?}", (&x1, &y1));
+        println!("p2: {:?}", (&x2, &y2));
+
+        assert_eq!(
+            (op.unwrap().as_str(), x1, y1, x2, y2),
+            ("turn off", Ok(660), Ok(55), Ok(986), Ok(197))
+        );
+    }
+}

src/main.rs

@@ -1,17 +1,15 @@
 use eyes::*;
 
 fn main() {
-    let input = "#loll1 @ 338,764: 20x24";
-    let pattern = "#{} @ {},{}: {}x{}";
+    let input = "turn off 660,55 through 986,197";
+    let template = "{} {},{} through {},{}";
 
-    println!("input: {}", input);
-    println!("pattern: {}", pattern);
+    println!("input: '{}'", input);
+    println!("pattern: '{}'", template);
 
-    let (id, x, y, w, h) = parse!(input, pattern, String, f64, f32, usize, isize);
+    let (op, x1, y1, x2, y2) = try_parse!(input, template, String, usize, usize, usize, usize);
 
-    println!("id: {:?}", id);
-    println!("x: {:?}", x);
-    println!("y: {:?}", y);
-    println!("w: {:?}", w);
-    println!("h: {:?}", h);
+    println!("op: {:?}", op);
+    println!("p1: {:?}", (x1, y1));
+    println!("p2: {:?}", (x2, y2));
 }