Fix Index source map lookup

src/types.rs

@@ -619,7 +619,7 @@ impl SourceMap {
 
         while low < high {
             let mid = (low + high) / 2;
-            let ii = &self.index[mid as usize];
+            let ii = &self.index[mid];
             if (line, col) < (ii.0, ii.1) {
                 high = mid;
             } else {
@@ -628,10 +628,12 @@ impl SourceMap {
         }
 
         if low > 0 && low <= self.index.len() {
-            self.get_token(self.index[low as usize - 1].2)
-        } else {
-            None
+            let ii = &self.index[low - 1];
+            if line == ii.0 {
+                return self.get_token(ii.2);
+            }
         }
+        None
     }
 
     /// Given a location, name and minified source file resolve a minified
@@ -935,15 +937,27 @@ impl SourceMapIndex {
     /// If a sourcemap is encountered that is not embedded but just
     /// externally referenced it is silently skipped.
     pub fn lookup_token(&self, line: u32, col: u32) -> Option<Token<'_>> {
-        for section in self.sections() {
-            let (off_line, off_col) = section.get_offset();
-            if off_line < line || off_col < col {
-                continue;
+        let mut low = 0;
+        let mut high = self.sections.len();
+
+        while low < high {
+            let mid = (low + high) / 2;
+            let section = &self.sections[mid];
+            if (line, col) < section.get_offset() {
+                high = mid;
+            } else {
+                low = mid + 1;
             }
+        }
+
+        if low > 0 && low <= self.sections.len() {
+            let section = &self.sections[low - 1];
+            let (off_line, off_col) = section.get_offset();
             if let Some(map) = section.get_sourcemap() {
-                if let Some(tok) = map.lookup_token(line - off_line, col - off_col) {
-                    return Some(tok);
-                }
+                return map.lookup_token(
+                    line - off_line,
+                    if line == off_line { col - off_col } else { col },
+                );
             }
         }
         None

tests/test_index.rs

@@ -23,7 +23,7 @@ fn test_basic_indexed_sourcemap() {
             {
                 "offset": {
                     "line": 1,
-                    "column": 0
+                    "column": 1
                 },
                 "map": {
                     "version":3,
@@ -95,6 +95,24 @@ fn test_basic_indexed_sourcemap() {
             .unwrap_or_else(|| panic!("no source for {}", filename));
         assert_eq!(&view.lines().collect::<Vec<_>>(), ref_contents);
     }
+
+    assert_eq!(
+        ism.lookup_token(0, 0).unwrap().to_tuple(),
+        ("file1.js", 0, 0, None)
+    );
+    assert_eq!(ism.lookup_token(1, 0), None);
+    assert_eq!(
+        ism.lookup_token(1, 1).unwrap().to_tuple(),
+        ("file2.js", 0, 0, None)
+    );
+    assert_eq!(
+        ism.lookup_token(1, 8).unwrap().to_tuple(),
+        ("file2.js", 0, 0, None)
+    );
+    assert_eq!(
+        ism.lookup_token(1, 9).unwrap().to_tuple(),
+        ("file2.js", 0, 9, Some("multiply"))
+    );
 }
 
 #[test]

tests/test_regular.rs

@@ -0,0 +1,34 @@
+use sourcemap::SourceMap;
+
+#[test]
+fn test_basic_sourcemap() {
+    let input: &[_] = b"{
+        \"version\":3,
+        \"sources\":[\"coolstuff.js\"],
+        \"names\":[\"x\",\"alert\"],
+        \"mappings\":\"AAAA,GAAIA,GAAI,EACR,IAAIA,GAAK,EAAG,CACVC,MAAM\"
+    }";
+    let sm = SourceMap::from_reader(input).unwrap();
+
+    assert_eq!(
+        sm.lookup_token(0, 0).unwrap().to_tuple(),
+        ("coolstuff.js", 0, 0, None)
+    );
+    assert_eq!(
+        sm.lookup_token(0, 3).unwrap().to_tuple(),
+        ("coolstuff.js", 0, 4, Some("x"))
+    );
+    assert_eq!(
+        sm.lookup_token(0, 24).unwrap().to_tuple(),
+        ("coolstuff.js", 2, 8, None)
+    );
+
+    // Lines continue out to infinity
+    assert_eq!(
+        sm.lookup_token(0, 1000).unwrap().to_tuple(),
+        ("coolstuff.js", 2, 8, None)
+    );
+
+    // Token must be on the same line to be found.
+    assert_eq!(sm.lookup_token(1000, 0), None);
+}