From cf62dc3d8c9694f9fdf4105c8590ba7cdebed9b1 Mon Sep 17 00:00:00 2001
From: Pelle Johnsen <pelle.johnsen@gmail.com>
Date: Sun, 5 Jul 2020 15:35:20 +0200
Subject: [PATCH] Glsl new multi line comments (#103)

* Add multi line comment support to glsl-new

* Fix glsl-new TokenMetadata for multi line comments
---
 src/front/glsl_new/lex.rs       | 39 ++++++++++++++++++++-------------
 src/front/glsl_new/lex_tests.rs | 26 ++++++++++++++++++++++
 src/front/glsl_new/parser.rs    |  3 +++
 3 files changed, 53 insertions(+), 15 deletions(-)

diff --git a/src/front/glsl_new/lex.rs b/src/front/glsl_new/lex.rs
index 0b6d675025..eb05603e24 100644
--- a/src/front/glsl_new/lex.rs
+++ b/src/front/glsl_new/lex.rs
@@ -181,13 +181,10 @@ pub fn consume_token(mut input: &str) -> (Option<Token>, &str) {
                     meta.chars.end = start + 2;
                     (Some(Token::MulAssign(meta)), chars.as_str())
                 }
-                //TODO: multi-line comments
-                // Some('/') => (
-                //     Token::MultiLineCommentClose,
-                //     chars.as_str(),
-                //     start,
-                //     start + 2,
-                // ),
+                Some('/') => {
+                    meta.chars.end = start + 2;
+                    (Some(Token::CommentEnd((meta, ()))), chars.as_str())
+                }
                 _ => (Some(Token::MulAssign(meta)), input),
             }
         }
@@ -199,13 +196,10 @@ pub fn consume_token(mut input: &str) -> (Option<Token>, &str) {
                     (Some(Token::DivAssign(meta)), chars.as_str())
                 }
                 Some('/') => (None, ""),
-                //TODO: multi-line comments
-                // Some('*') => (
-                //     Token::MultiLineCommentOpen,
-                //     chars.as_str(),
-                //     start,
-                //     start + 2,
-                // ),
+                Some('*') => {
+                    meta.chars.end = start + 2;
+                    (Some(Token::CommentStart((meta, ()))), chars.as_str())
+                }
                 _ => (Some(Token::Slash(meta)), input),
             }
         }
@@ -237,6 +231,7 @@ pub struct Lexer<'a> {
     input: String,
     line: usize,
     offset: usize,
+    inside_comment: bool,
 }
 
 impl<'a> Lexer<'a> {
@@ -259,6 +254,7 @@ impl<'a> Lexer<'a> {
             input,
             line,
             offset: 0,
+            inside_comment: false,
         }
     }
 
@@ -274,7 +270,20 @@ impl<'a> Lexer<'a> {
             meta.chars.start += self.offset;
             meta.chars.end += self.offset;
             self.offset += end;
-            Some(token)
+            if !self.inside_comment {
+                match token {
+                    Token::CommentStart(_) => {
+                        self.inside_comment = true;
+                        self.next()
+                    }
+                    _ => Some(token),
+                }
+            } else {
+                if let Token::CommentEnd(_) = token {
+                    self.inside_comment = false;
+                }
+                self.next()
+            }
         } else {
             let (line, input) = self.lines.next()?;
 
diff --git a/src/front/glsl_new/lex_tests.rs b/src/front/glsl_new/lex_tests.rs
index 377f17f5fa..1da89d80f3 100644
--- a/src/front/glsl_new/lex_tests.rs
+++ b/src/front/glsl_new/lex_tests.rs
@@ -61,6 +61,32 @@ fn glsl_lex_line_comment() {
     );
 }
 
+#[test]
+fn glsl_lex_multi_line_comment() {
+    let source = "void main /* comment [] {}\n/**\n{}*/{}";
+    let lex = Lexer::new(source);
+    let tokens: Vec<Token> = lex.collect();
+    assert_eq!(tokens.len(), 4);
+
+    let mut iter = tokens.iter();
+    assert_eq!(
+        format!("{:?}", iter.next().unwrap()),
+        "Void(TokenMetadata { line: 0, chars: 0..4 })"
+    );
+    assert_eq!(
+        format!("{:?}", iter.next().unwrap()),
+        "Identifier((TokenMetadata { line: 0, chars: 5..9 }, \"main\"))"
+    );
+    assert_eq!(
+        format!("{:?}", iter.next().unwrap()),
+        "LeftBrace(TokenMetadata { line: 2, chars: 4..5 })"
+    );
+    assert_eq!(
+        format!("{:?}", iter.next().unwrap()),
+        "RightBrace(TokenMetadata { line: 2, chars: 5..6 })"
+    );
+}
+
 #[test]
 fn glsl_lex_identifier() {
     let source = "id123_OK 92No æNoø No¾ No好";
diff --git a/src/front/glsl_new/parser.rs b/src/front/glsl_new/parser.rs
index 10ac3af5c8..194dca93d7 100644
--- a/src/front/glsl_new/parser.rs
+++ b/src/front/glsl_new/parser.rs
@@ -25,6 +25,9 @@ pomelo! {
     }
 
     %type Unknown char;
+    %type CommentStart ();
+    %type CommentEnd ();
+
     %type Identifier String;
     %type IntConstant i64;
     %type UintConstant u64;