From 842079a3cd7528282d6ccc2a991f894bcaea4bf2 Mon Sep 17 00:00:00 2001
From: Pelle Johnsen <pelle.johnsen@gmail.com>
Date: Thu, 1 Oct 2020 12:31:16 +0000
Subject: [PATCH] [glsl-in] Handle spacing for preproces directives

---
 src/front/glsl/lex.rs          | 29 ++++++++++++++++++++---------
 src/front/glsl/parser_tests.rs | 16 ++++++++++++++++
 2 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/src/front/glsl/lex.rs b/src/front/glsl/lex.rs
index 6502bbb5aa..f0b9e6b95a 100644
--- a/src/front/glsl/lex.rs
+++ b/src/front/glsl/lex.rs
@@ -16,7 +16,7 @@ fn consume_any(input: &str, what: impl Fn(char) -> bool) -> (&str, &str, usize)
     (o, i, pos)
 }
 
-pub fn consume_token(mut input: &str) -> (Option<Token>, &str) {
+pub fn consume_token(mut input: &str, start_of_line: bool) -> (Option<Token>, &str) {
     let start = input
         .find(|c: char| !c.is_whitespace())
         .unwrap_or_else(|| input.chars().count());
@@ -246,13 +246,21 @@ pub fn consume_token(mut input: &str) -> (Option<Token>, &str) {
             }
         }
         '#' => {
-            input = chars.as_str();
-            let (word, rest, pos) = consume_any(input, |c| c.is_alphanumeric() || c == '_');
-            meta.chars.end = start + 1 + pos;
-            match word {
-                "version" => (Some(Token::Version(meta)), rest),
-                _ => (None, input),
-            }
+            if start_of_line {
+                input = chars.as_str();
+
+                // skip whitespace
+                let word_start = input
+                    .find(|c: char| !c.is_whitespace())
+                    .unwrap_or_else(|| input.chars().count());
+                input = &input[word_start..];
+
+                let (word, rest, pos) = consume_any(input, |c| c.is_alphanumeric() || c == '_');
+                meta.chars.end = start + word_start + 1 + pos;
+                match word {
+                    "version" => (Some(Token::Version(meta)), rest),
+                    _ => (None, input),
+                }
 
             //TODO: preprocessor
             // if chars.next() == Some(cur) {
@@ -260,6 +268,9 @@ pub fn consume_token(mut input: &str) -> (Option<Token>, &str) {
             // } else {
             //     (Token::Preprocessor, input, start, start + 1)
             // }
+            } else {
+                (Some(Token::Unknown((meta, '#'))), chars.as_str())
+            }
         }
         '~' => (Some(Token::Tilde(meta)), chars.as_str()),
         '?' => (Some(Token::Question(meta)), chars.as_str()),
@@ -302,7 +313,7 @@ impl<'a> Lexer<'a> {
 
     #[must_use]
     pub fn next(&mut self) -> Option<Token> {
-        let (token, rest) = consume_token(&self.input);
+        let (token, rest) = consume_token(&self.input, self.offset == 0);
 
         if let Some(mut token) = token {
             self.input = String::from(rest);
diff --git a/src/front/glsl/parser_tests.rs b/src/front/glsl/parser_tests.rs
index 14db86fda0..77cdac5571 100644
--- a/src/front/glsl/parser_tests.rs
+++ b/src/front/glsl/parser_tests.rs
@@ -49,7 +49,23 @@ fn version() {
         "InvalidProfile(TokenMetadata { line: 0, chars: 13..18 }, \"smart\")"
     );
 
+    assert_eq!(
+        format!(
+            "{:?}",
+            parse_program("#version 450\nvoid f(){} #version 450", ShaderStage::Vertex)
+                .err()
+                .unwrap()
+        ),
+        "InvalidToken(Unknown((TokenMetadata { line: 1, chars: 11..12 }, \'#\')))"
+    );
+
     // valid versions
+    let program = parse_program("  #  version 450\nvoid main() {}", ShaderStage::Vertex).unwrap();
+    assert_eq!(
+        format!("{:?}", (program.version, program.profile)),
+        "(450, Core)"
+    );
+
     let program = parse_program("#version 450\nvoid main() {}", ShaderStage::Vertex).unwrap();
     assert_eq!(
         format!("{:?}", (program.version, program.profile)),