Merge pull request #27 from ratel-rust/scientific_numbers

Adding support for scientific numbers
Closes #12 🎉

Author: maciejhirsz

core/src/tokenizer.rs

@@ -690,6 +690,10 @@ define_handlers! {
 
                     return Ok(Literal(tok.read_float(start)));
                 },
+                b'e' | b'E' => {
+                    tok.bump();
+                    return Ok(Literal(tok.read_scientific(start)));
+                }
                 _ => break,
             }
         }
@@ -715,6 +719,10 @@ define_handlers! {
 
                     return Ok(Literal(tok.read_float(start)));
                 },
+                b'e' | b'E' => {
+                    tok.bump();
+                    return Ok(Literal(tok.read_scientific(start)));
+                },
                 _ => break,
             }
         }
@@ -1054,7 +1062,6 @@ impl<'a> Tokenizer<'a> {
 
     #[inline]
     fn read_octal(&mut self, start: usize) -> Value {
-
         while !self.is_eof() {
             match self.read_byte() {
                 b'0'...b'7' => self.bump(),
@@ -1081,6 +1088,32 @@ impl<'a> Tokenizer<'a> {
 
     #[inline]
     fn read_float(&mut self, start: usize) -> Value {
+        while !self.is_eof() {
+            let ch = self.read_byte();
+            match ch {
+                b'0'...b'9'  => self.bump(),
+                b'e' | b'E'  => {
+                    self.bump();
+                    return self.read_scientific(start);
+                },
+                _            => break
+            }
+        }
+
+        let value = self.slice_source(start, self.index);
+
+        Value::Number(value)
+    }
+
+    #[inline]
+    fn read_scientific(&mut self, start: usize) -> Value {
+        if !self.is_eof() {
+            match self.read_byte() {
+                b'-' | b'+' => self.bump(),
+                _           => {}
+            }
+        }
+
         while !self.is_eof() {
             let ch = self.read_byte();
             match ch {
@@ -1093,4 +1126,5 @@ impl<'a> Tokenizer<'a> {
 
         Value::Number(value)
     }
+
 }

core/tests/tokenizer.rs

@@ -148,6 +148,17 @@ fn test_tokenizer_literals() {
     assert_token!("0O113", lit_num!("0O113"), "Value::Number");
 }
 
+#[test]
+fn test_scientifix_numbers() {
+    assert_token!("0e-2", Literal(Value::Number("0e-2".into())), "Value::Number");
+    assert_token!("0e2", Literal(Value::Number("0e2".into())), "Value::Number");
+    assert_token!("2e3", Literal(Value::Number("2e3".into())), "Value::Number");
+    assert_token!("2e-3", Literal(Value::Number("2e-3".into())), "Value::Number");
+    assert_token!("2e+3", Literal(Value::Number("2e+3".into())), "Value::Number");
+    assert_token!("0.2e3", Literal(Value::Number("0.2e3".into())), "Value::Number");
+    assert_token!("0.2e-3", Literal(Value::Number("0.2e-3".into())), "Value::Number");
+}
+
 #[test]
 fn test_tokenizer_reserved() {
     assert_token!("enum", Reserved(ReservedKind::Enum), "ReservedKind::Enum");