loop over shader until everything has been processed

crates/bevy_render/src/render_resource/shader.rs

@@ -362,46 +362,59 @@ impl ShaderProcessor {
 
  let shader_defs = HashSet::<String>::from_iter(shader_defs.iter().cloned());
  let mut scopes = vec![true];
- let mut final_string = String::new();
- for line in shader_str.split('\n') {
- if let Some(cap) = self.ifdef_regex.captures(line) {
- let def = cap.get(1).unwrap();
- scopes.push(*scopes.last().unwrap() && shader_defs.contains(def.as_str()));
- } else if let Some(cap) = self.ifndef_regex.captures(line) {
- let def = cap.get(1).unwrap();
- scopes.push(*scopes.last().unwrap() && !shader_defs.contains(def.as_str()));
- } else if self.else_regex.is_match(line) {
- let mut is_parent_scope_truthy = true;
- if scopes.len() > 1 {
- is_parent_scope_truthy = scopes[scopes.len() - 2];
+ let mut processing = shader_str.to_string();
+ let final_string = loop {
+ let mut processed = String::new();
+ let mut changed = false;
+ for line in processing.split('\n') {
+ if let Some(cap) = self.ifdef_regex.captures(line) {
+ let def = cap.get(1).unwrap();
+ scopes.push(*scopes.last().unwrap() && shader_defs.contains(def.as_str()));
+ changed = true;
+ } else if let Some(cap) = self.ifndef_regex.captures(line) {
+ let def = cap.get(1).unwrap();
+ scopes.push(*scopes.last().unwrap() && !shader_defs.contains(def.as_str()));
+ changed = true;
+ } else if self.else_regex.is_match(line) {
+ let mut is_parent_scope_truthy = true;
+ if scopes.len() > 1 {
+ is_parent_scope_truthy = scopes[scopes.len() - 2];
+ }
+ if let Some(last) = scopes.last_mut() {
+ *last = is_parent_scope_truthy && !*last;
+ }
+ changed = true;
+ } else if self.endif_regex.is_match(line) {
+ scopes.pop();
+ if scopes.is_empty() {
+ return Err(ProcessShaderError::TooManyEndIfs);
+ }
+ changed = true;
+ } else if let Some(cap) = SHADER_IMPORT_PROCESSOR
+ .import_asset_path_regex
+ .captures(line)
+ {
+ let import = ShaderImport::AssetPath(cap.get(1).unwrap().as_str().to_string());
+ apply_import(import_handles, shaders, &import, shader, &mut processed)?;
+ changed = true;
+ } else if let Some(cap) = SHADER_IMPORT_PROCESSOR
+ .import_custom_path_regex
+ .captures(line)
+ {
+ let import = ShaderImport::Custom(cap.get(1).unwrap().as_str().to_string());
+ apply_import(import_handles, shaders, &import, shader, &mut processed)?;
+ changed = true;
+ } else if *scopes.last().unwrap() {
+ processed.push_str(line);
+ processed.push('\n');
  }
- if let Some(last) = scopes.last_mut() {
- *last = is_parent_scope_truthy && !*last;
- }
- } else if self.endif_regex.is_match(line) {
- scopes.pop();
- if scopes.is_empty() {
- return Err(ProcessShaderError::TooManyEndIfs);
- }
- } else if let Some(cap) = SHADER_IMPORT_PROCESSOR
- .import_asset_path_regex
- .captures(line)
- {
- let import = ShaderImport::AssetPath(cap.get(1).unwrap().as_str().to_string());
- apply_import(import_handles, shaders, &import, shader, &mut final_string)?;
- } else if let Some(cap) = SHADER_IMPORT_PROCESSOR
- .import_custom_path_regex
- .captures(line)
- {
- let import = ShaderImport::Custom(cap.get(1).unwrap().as_str().to_string());
- apply_import(import_handles, shaders, &import, shader, &mut final_string)?;
- } else if *scopes.last().unwrap() {
- final_string.push_str(line);
- final_string.push('\n');
  }
- }
-
- final_string.pop();
+ processed.pop();
+ if !changed {
+ break processed;
+ }
+ processing = processed.clone();
+ };
 
  if scopes.len() != 1 {
  return Err(ProcessShaderError::NotEnoughEndIfs);
@@ -1094,4 +1107,51 @@ fn vertex(
  .unwrap();
  assert_eq!(result.get_wgsl_source().unwrap(), EXPECTED);
  }
+
+ #[test]
+ fn process_import_ifdef() {
+ #[rustfmt::skip]
+ const FOO: &str = r"
+#ifdef IMPORT_MISSING
+fn in_import_missing() { }
+#endif
+#ifdef IMPORT_PRESENT
+fn in_import_present() { }
+#endif
+";
+ #[rustfmt::skip]
+ const INPUT: &str = r"
+#import FOO
+#ifdef MAIN_MISSING
+fn in_main_missing() { }
+#endif
+#ifdef MAIN_PRESENT
+fn in_main_present() { }
+#endif
+";
+ #[rustfmt::skip]
+ const EXPECTED: &str = r"
+
+fn in_import_present() { }
+fn in_main_present() { }
+";
+ let processor = ShaderProcessor::default();
+ let mut shaders = HashMap::default();
+ let mut import_handles = HashMap::default();
+ let foo_handle = Handle::<Shader>::default();
+ shaders.insert(foo_handle.clone_weak(), Shader::from_wgsl(FOO));
+ import_handles.insert(
+ ShaderImport::Custom("FOO".to_string()),
+ foo_handle.clone_weak(),
+ );
+ let result = processor
+ .process(
+ &Shader::from_wgsl(INPUT),
+ &["MAIN_PRESENT".to_string(), "IMPORT_PRESENT".to_string()],
+ &shaders,
+ &import_handles,
+ )
+ .unwrap();
+ assert_eq!(result.get_wgsl_source().unwrap(), EXPECTED);
+ }
 }