7 files changed, 149 insertions, 25 deletions

diff --git a/crates/ra_syntax/Cargo.toml b/crates/ra_syntax/Cargo.toml
index 97b6b047f..9ef8dee5d 100644
--- a/crates/ra_syntax/Cargo.toml
+++ b/crates/ra_syntax/Cargo.toml
@@ -11,6 +11,7 @@ repository = "https://github.com/rust-analyzer/rust-analyzer"
 unicode-xid = "0.1.0"
 itertools = "0.8.0"
 rowan = "0.6.0-pre.1"
+ra_rustc_lexer = { version = "0.1.0-pre.1", features = [ "unicode-xid" ] }
 
 # ideally, `serde` should be enabled by `ra_lsp_server`, but we enable it here
 # to reduce number of compilations
diff --git a/crates/ra_syntax/src/parsing/lexer.rs b/crates/ra_syntax/src/parsing/lexer.rs
index 60cf37047..1c818fdf4 100644
--- a/crates/ra_syntax/src/parsing/lexer.rs
+++ b/crates/ra_syntax/src/parsing/lexer.rs
@@ -30,19 +30,119 @@ pub struct Token {
 
 /// Break a string up into its component tokens
 pub fn tokenize(text: &str) -> Vec<Token> {
+    if text.is_empty() {
+        return vec![];
+    }
     let mut text = text;
     let mut acc = Vec::new();
+    if let Some(len) = ra_rustc_lexer::strip_shebang(text) {
+        acc.push(Token { kind: SHEBANG, len: TextUnit::from_usize(len) });
+        text = &text[len..];
+    }
     while !text.is_empty() {
-        let token = next_token(text);
+        let rustc_token = ra_rustc_lexer::first_token(text);
+        macro_rules! decompose {
+            ($t1:expr, $t2:expr) => {{
+                acc.push(Token { kind: $t1, len: 1.into() });
+                acc.push(Token { kind: $t2, len: 1.into() });
+                text = &text[2..];
+                continue;
+            }};
+            ($t1:expr, $t2:expr, $t3:expr) => {{
+                acc.push(Token { kind: $t1, len: 1.into() });
+                acc.push(Token { kind: $t2, len: 1.into() });
+                acc.push(Token { kind: $t3, len: 1.into() });
+                text = &text[3..];
+                continue;
+            }};
+        }
+        let kind = match rustc_token.kind {
+            ra_rustc_lexer::TokenKind::LineComment => COMMENT,
+            ra_rustc_lexer::TokenKind::BlockComment { .. } => COMMENT,
+            ra_rustc_lexer::TokenKind::Whitespace => WHITESPACE,
+            ra_rustc_lexer::TokenKind::Ident => {
+                let token_text = &text[..rustc_token.len];
+                if token_text == "_" {
+                    UNDERSCORE
+                } else {
+                    SyntaxKind::from_keyword(&text[..rustc_token.len]).unwrap_or(IDENT)
+                }
+            }
+            ra_rustc_lexer::TokenKind::RawIdent => IDENT,
+            ra_rustc_lexer::TokenKind::Literal { kind, .. } => match kind {
+                ra_rustc_lexer::LiteralKind::Int { .. } => INT_NUMBER,
+                ra_rustc_lexer::LiteralKind::Float { .. } => FLOAT_NUMBER,
+                ra_rustc_lexer::LiteralKind::Char { .. } => CHAR,
+                ra_rustc_lexer::LiteralKind::Byte { .. } => BYTE,
+                ra_rustc_lexer::LiteralKind::Str { .. } => STRING,
+                ra_rustc_lexer::LiteralKind::ByteStr { .. } => BYTE_STRING,
+                ra_rustc_lexer::LiteralKind::RawStr { .. } => RAW_STRING,
+                ra_rustc_lexer::LiteralKind::RawByteStr { .. } => RAW_BYTE_STRING,
+            },
+            ra_rustc_lexer::TokenKind::Lifetime { .. } => LIFETIME,
+            ra_rustc_lexer::TokenKind::Semi => SEMI,
+            ra_rustc_lexer::TokenKind::Comma => COMMA,
+            ra_rustc_lexer::TokenKind::DotDotDot => decompose!(DOT, DOT, DOT),
+            ra_rustc_lexer::TokenKind::DotDotEq => decompose!(DOT, DOT, EQ),
+            ra_rustc_lexer::TokenKind::DotDot => decompose!(DOT, DOT),
+            ra_rustc_lexer::TokenKind::Dot => DOT,
+            ra_rustc_lexer::TokenKind::OpenParen => L_PAREN,
+            ra_rustc_lexer::TokenKind::CloseParen => R_PAREN,
+            ra_rustc_lexer::TokenKind::OpenBrace => L_CURLY,
+            ra_rustc_lexer::TokenKind::CloseBrace => R_CURLY,
+            ra_rustc_lexer::TokenKind::OpenBracket => L_BRACK,
+            ra_rustc_lexer::TokenKind::CloseBracket => R_BRACK,
+            ra_rustc_lexer::TokenKind::At => AT,
+            ra_rustc_lexer::TokenKind::Pound => POUND,
+            ra_rustc_lexer::TokenKind::Tilde => TILDE,
+            ra_rustc_lexer::TokenKind::Question => QUESTION,
+            ra_rustc_lexer::TokenKind::ColonColon => decompose!(COLON, COLON),
+            ra_rustc_lexer::TokenKind::Colon => COLON,
+            ra_rustc_lexer::TokenKind::Dollar => DOLLAR,
+            ra_rustc_lexer::TokenKind::EqEq => decompose!(EQ, EQ),
+            ra_rustc_lexer::TokenKind::Eq => EQ,
+            ra_rustc_lexer::TokenKind::FatArrow => decompose!(EQ, R_ANGLE),
+            ra_rustc_lexer::TokenKind::Ne => decompose!(EXCL, EQ),
+            ra_rustc_lexer::TokenKind::Not => EXCL,
+            ra_rustc_lexer::TokenKind::Le => decompose!(L_ANGLE, EQ),
+            ra_rustc_lexer::TokenKind::LArrow => decompose!(COLON, MINUS),
+            ra_rustc_lexer::TokenKind::Lt => L_ANGLE,
+            ra_rustc_lexer::TokenKind::ShlEq => decompose!(L_ANGLE, L_ANGLE, EQ),
+            ra_rustc_lexer::TokenKind::Shl => decompose!(L_ANGLE, L_ANGLE),
+            ra_rustc_lexer::TokenKind::Ge => decompose!(R_ANGLE, EQ),
+            ra_rustc_lexer::TokenKind::Gt => R_ANGLE,
+            ra_rustc_lexer::TokenKind::ShrEq => decompose!(R_ANGLE, R_ANGLE, EQ),
+            ra_rustc_lexer::TokenKind::Shr => decompose!(R_ANGLE, R_ANGLE),
+            ra_rustc_lexer::TokenKind::RArrow => decompose!(MINUS, R_ANGLE),
+            ra_rustc_lexer::TokenKind::Minus => MINUS,
+            ra_rustc_lexer::TokenKind::MinusEq => decompose!(MINUS, EQ),
+            ra_rustc_lexer::TokenKind::And => AMP,
+            ra_rustc_lexer::TokenKind::AndAnd => decompose!(AMP, AMP),
+            ra_rustc_lexer::TokenKind::AndEq => decompose!(AMP, EQ),
+            ra_rustc_lexer::TokenKind::Or => PIPE,
+            ra_rustc_lexer::TokenKind::OrOr => decompose!(PIPE, PIPE),
+            ra_rustc_lexer::TokenKind::OrEq => decompose!(PIPE, EQ),
+            ra_rustc_lexer::TokenKind::PlusEq => decompose!(PLUS, EQ),
+            ra_rustc_lexer::TokenKind::Plus => PLUS,
+            ra_rustc_lexer::TokenKind::StarEq => decompose!(STAR, EQ),
+            ra_rustc_lexer::TokenKind::Star => STAR,
+            ra_rustc_lexer::TokenKind::SlashEq => decompose!(SLASH, EQ),
+            ra_rustc_lexer::TokenKind::Slash => SLASH,
+            ra_rustc_lexer::TokenKind::CaretEq => decompose!(CARET, EQ),
+            ra_rustc_lexer::TokenKind::Caret => CARET,
+            ra_rustc_lexer::TokenKind::PercentEq => decompose!(PERCENT, EQ),
+            ra_rustc_lexer::TokenKind::Percent => PERCENT,
+            ra_rustc_lexer::TokenKind::Unknown => ERROR,
+        };
+        let token = Token { kind, len: TextUnit::from_usize(rustc_token.len) };
         acc.push(token);
-        let len: u32 = token.len.into();
-        text = &text[len as usize..];
+        text = &text[rustc_token.len..];
     }
     acc
 }
 
 /// Get the next token from a string
-pub fn next_token(text: &str) -> Token {
+fn next_token(text: &str) -> Token {
     assert!(!text.is_empty());
     let mut ptr = Ptr::new(text);
     let c = ptr.bump().unwrap();
diff --git a/crates/ra_syntax/tests/data/lexer/0004_numbers.txt b/crates/ra_syntax/tests/data/lexer/0004_numbers.txt
index 39988aedc..7bb89b8ae 100644
--- a/crates/ra_syntax/tests/data/lexer/0004_numbers.txt
+++ b/crates/ra_syntax/tests/data/lexer/0004_numbers.txt
@@ -12,9 +12,9 @@ INT_NUMBER 2 "0_"
 WHITESPACE 1 " "
 FLOAT_NUMBER 2 "0."
 WHITESPACE 1 " "
-INT_NUMBER 2 "0e"
+FLOAT_NUMBER 2 "0e"
 WHITESPACE 1 " "
-INT_NUMBER 2 "0E"
+FLOAT_NUMBER 2 "0E"
 WHITESPACE 1 " "
 INT_NUMBER 2 "0z"
 WHITESPACE 1 "\n"
@@ -32,9 +32,9 @@ INT_NUMBER 6 "0_1279"
 WHITESPACE 1 " "
 FLOAT_NUMBER 6 "0.1279"
 WHITESPACE 1 " "
-INT_NUMBER 6 "0e1279"
+FLOAT_NUMBER 6 "0e1279"
 WHITESPACE 1 " "
-INT_NUMBER 6 "0E1279"
+FLOAT_NUMBER 6 "0E1279"
 WHITESPACE 1 "\n"
 INT_NUMBER 1 "0"
 DOT 1 "."
@@ -47,9 +47,7 @@ IDENT 3 "foo"
 L_PAREN 1 "("
 R_PAREN 1 ")"
 WHITESPACE 1 "\n"
-INT_NUMBER 2 "0e"
-PLUS 1 "+"
-INT_NUMBER 1 "1"
+FLOAT_NUMBER 4 "0e+1"
 WHITESPACE 1 "\n"
 INT_NUMBER 1 "0"
 DOT 1 "."
diff --git a/crates/ra_syntax/tests/data/lexer/0014_unclosed_char.txt b/crates/ra_syntax/tests/data/lexer/0014_unclosed_char.txt
index 812dfbc18..737a300ee 100644
--- a/crates/ra_syntax/tests/data/lexer/0014_unclosed_char.txt
+++ b/crates/ra_syntax/tests/data/lexer/0014_unclosed_char.txt
@@ -1 +1 @@
-CHAR 2 "\'1"
+LIFETIME 2 "\'1"
diff --git a/crates/ra_syntax/tests/data/parser/err/0002_duplicate_shebang.txt b/crates/ra_syntax/tests/data/parser/err/0002_duplicate_shebang.txt
index 76d186a3c..84867026f 100644
--- a/crates/ra_syntax/tests/data/parser/err/0002_duplicate_shebang.txt
+++ b/crates/ra_syntax/tests/data/parser/err/0002_duplicate_shebang.txt
@@ -1,7 +1,39 @@
 SOURCE_FILE@[0; 42)
   SHEBANG@[0; 20) "#!/use/bin/env rusti"
   WHITESPACE@[20; 21) "\n"
-  ERROR@[21; 41)
-    SHEBANG@[21; 41) "#!/use/bin/env rusti"
+  ATTR@[21; 23)
+    POUND@[21; 22) "#"
+    EXCL@[22; 23) "!"
+  ERROR@[23; 24)
+    SLASH@[23; 24) "/"
+  USE_ITEM@[24; 28)
+    USE_KW@[24; 27) "use"
+    ERROR@[27; 28)
+      SLASH@[27; 28) "/"
+  MACRO_CALL@[28; 31)
+    PATH@[28; 31)
+      PATH_SEGMENT@[28; 31)
+        NAME_REF@[28; 31)
+          IDENT@[28; 31) "bin"
+  ERROR@[31; 32)
+    SLASH@[31; 32) "/"
+  MACRO_CALL@[32; 41)
+    PATH@[32; 35)
+      PATH_SEGMENT@[32; 35)
+        NAME_REF@[32; 35)
+          IDENT@[32; 35) "env"
+    WHITESPACE@[35; 36) " "
+    NAME@[36; 41)
+      IDENT@[36; 41) "rusti"
   WHITESPACE@[41; 42) "\n"
-error 21: expected an item
+error 23: expected `[`
+error 23: expected an item
+error 27: expected one of `*`, `::`, `{`, `self`, `super` or an indentifier
+error 28: expected SEMI
+error 31: expected EXCL
+error 31: expected `{`, `[`, `(`
+error 31: expected SEMI
+error 31: expected an item
+error 35: expected EXCL
+error 41: expected `{`, `[`, `(`
+error 41: expected SEMI
diff --git a/crates/ra_syntax/tests/data/parser/err/0030_string_suffixes.rs b/crates/ra_syntax/tests/data/parser/ok/0030_string_suffixes.rs
index 261aad1fb..261aad1fb 100644
--- a/crates/ra_syntax/tests/data/parser/err/0030_string_suffixes.rs
+++ b/crates/ra_syntax/tests/data/parser/ok/0030_string_suffixes.rs
diff --git a/crates/ra_syntax/tests/data/parser/err/0030_string_suffixes.txt b/crates/ra_syntax/tests/data/parser/ok/0030_string_suffixes.txt
index b0acfa5d2..4f7e809c5 100644
--- a/crates/ra_syntax/tests/data/parser/err/0030_string_suffixes.txt
+++ b/crates/ra_syntax/tests/data/parser/ok/0030_string_suffixes.txt
@@ -11,7 +11,7 @@ SOURCE_FILE@[0; 112)
     BLOCK@[10; 111)
       L_CURLY@[10; 11) "{"
       WHITESPACE@[11; 16) "\n    "
-      LET_STMT@[16; 27)
+      LET_STMT@[16; 31)
         LET_KW@[16; 19) "let"
         WHITESPACE@[19; 20) " "
         PLACEHOLDER_PAT@[20; 21)
@@ -19,14 +19,8 @@ SOURCE_FILE@[0; 112)
         WHITESPACE@[21; 22) " "
         EQ@[22; 23) "="
         WHITESPACE@[23; 24) " "
-        LITERAL@[24; 27)
-          CHAR@[24; 27) "\'c\'"
-      EXPR_STMT@[27; 31)
-        PATH_EXPR@[27; 30)
-          PATH@[27; 30)
-            PATH_SEGMENT@[27; 30)
-              NAME_REF@[27; 30)
-                IDENT@[27; 30) "u32"
+        LITERAL@[24; 30)
+          CHAR@[24; 30) "\'c\'u32"
         SEMI@[30; 31) ";"
       WHITESPACE@[31; 36) "\n    "
       LET_STMT@[36; 60)
@@ -67,4 +61,3 @@ SOURCE_FILE@[0; 112)
       WHITESPACE@[109; 110) "\n"
       R_CURLY@[110; 111) "}"
   WHITESPACE@[111; 112) "\n"
-error 27: expected SEMI