implement block comments

gfx-rs · Jan 19, 2022 · 4315d79 · 4315d79
1 parent a1840be
commit 4315d79
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Showing 2 changed files with 38 additions and 4 deletions.
diff --git a/src/front/wgsl/lexer.rs b/src/front/wgsl/lexer.rs
@@ -356,9 +356,41 @@ fn consume_token(mut input: &str, generic: bool) -> (Token<'_>, &str) {
                 (Token::UnterminatedString, quote_content)
             }
         }
-        '/' if chars.as_str().starts_with('/') => {
-            let _ = chars.position(|c| c == '\n' || c == '\r');
-            (Token::Trivia, chars.as_str())
+        '/' => {
+            input = chars.as_str();
+            match chars.next() {
+                Some('/') => {
+                    let _ = chars.position(|c| c == '\n' || c == '\r');
+                    (Token::Trivia, chars.as_str())
+                }
+                Some('*') => {
+                    input = chars.as_str();
+
+                    let mut depth = 1;
+                    while let Some(c) = chars.next() {
+                        match c {
+                            '*' if chars.next() == Some('/') => {
+                                depth -= 1;
+                                if depth == 0 {
+                                    break;
+                                }
+                            }
+                            '/' if chars.next() == Some('*') => {
+                                depth += 1;
+                            }
+                            _ => {}
+                        }
+                    }
+
+                    if depth > 0 {
+                        (Token::UnterminatedBlockComment, input)
+                    } else {
+                        (Token::Trivia, chars.as_str())
+                    }
+                }
+                Some('=') => (Token::AssignmentOperation(cur), chars.as_str()),
+                _ => (Token::Operation(cur), input),
+            }
         }
         '-' => {
             let sub_input = chars.as_str();
@@ -369,7 +401,7 @@ fn consume_token(mut input: &str, generic: bool) -> (Token<'_>, &str) {
                 _ => (Token::Operation(cur), sub_input),
             }
         }
-        '+' | '*' | '/' | '%' | '^' => {
+        '+' | '*' | '%' | '^' => {
             input = chars.as_str();
             if chars.next() == Some('=') {
                 (Token::AssignmentOperation(cur), chars.as_str())

diff --git a/src/front/wgsl/mod.rs b/src/front/wgsl/mod.rs
@@ -72,6 +72,7 @@ pub enum Token<'a> {
     Arrow,
     Unknown(char),
     UnterminatedString,
+    UnterminatedBlockComment,
     Trivia,
     End,
 }
@@ -204,6 +205,7 @@ impl<'a> Error<'a> {
                                 Token::Arrow => "->".to_string(),
                                 Token::Unknown(c) => format!("unknown ('{}')", c),
                                 Token::UnterminatedString => "unterminated string".to_string(),
+                                Token::UnterminatedBlockComment => "unterminated block comment".to_string(),
                                 Token::Trivia => "trivia".to_string(),
                                 Token::End => "end".to_string(),
                             }