incr.comp.: Hash more pieces of crate metadata to detect changes there.

src/libsyntax/codemap.rs

@@ -21,8 +21,8 @@ pub use syntax_pos::*;
 pub use syntax_pos::hygiene::{ExpnFormat, ExpnInfo, NameAndSpan};
 pub use self::ExpnFormat::*;
 
-use std::cell::RefCell;
-use std::path::{Path,PathBuf};
+use std::cell::{RefCell, Ref};
+use std::path::{Path, PathBuf};
 use std::rc::Rc;
 
 use std::env;
@@ -103,11 +103,18 @@ impl FileLoader for RealFileLoader {
 //
 
 pub struct CodeMap {
-    pub files: RefCell<Vec<Rc<FileMap>>>,
+    // The `files` field should not be visible outside of libsyntax so that we
+    // can do proper dependency tracking.
+    pub(super) files: RefCell<Vec<Rc<FileMap>>>,
     file_loader: Box<FileLoader>,
     // This is used to apply the file path remapping as specified via
     // -Zremap-path-prefix to all FileMaps allocated within this CodeMap.
     path_mapping: FilePathMapping,
+    // The CodeMap will invoke this callback whenever a specific FileMap is
+    // accessed. The callback starts out as a no-op but when the dependency
+    // graph becomes available later during the compilation process, it is
+    // be replaced with something that notifies the dep-tracking system.
+    dep_tracking_callback: RefCell<Box<Fn(&FileMap)>>,
 }
 
 impl CodeMap {
@@ -116,6 +123,7 @@ impl CodeMap {
             files: RefCell::new(Vec::new()),
             file_loader: Box::new(RealFileLoader),
             path_mapping: path_mapping,
+            dep_tracking_callback: RefCell::new(Box::new(|_| {})),
         }
     }
 
@@ -126,6 +134,7 @@ impl CodeMap {
             files: RefCell::new(Vec::new()),
             file_loader: file_loader,
             path_mapping: path_mapping,
+            dep_tracking_callback: RefCell::new(Box::new(|_| {})),
         }
     }
 
@@ -133,6 +142,10 @@ impl CodeMap {
         &self.path_mapping
     }
 
+    pub fn set_dep_tracking_callback(&self, cb: Box<Fn(&FileMap)>) {
+        *self.dep_tracking_callback.borrow_mut() = cb;
+    }
+
     pub fn file_exists(&self, path: &Path) -> bool {
         self.file_loader.file_exists(path)
     }
@@ -142,6 +155,19 @@ impl CodeMap {
         Ok(self.new_filemap(path.to_str().unwrap().to_string(), src))
     }
 
+    pub fn files(&self) -> Ref<Vec<Rc<FileMap>>> {
+        let files = self.files.borrow();
+        for file in files.iter() {
+            (self.dep_tracking_callback.borrow())(file);
+        }
+        files
+    }
+
+    /// Only use this if you do your own dependency tracking!
+    pub fn files_untracked(&self) -> Ref<Vec<Rc<FileMap>>> {
+        self.files.borrow()
+    }
+
     fn next_start_pos(&self) -> usize {
         let files = self.files.borrow();
         match files.last() {
@@ -170,6 +196,7 @@ impl CodeMap {
         let filemap = Rc::new(FileMap {
             name: filename,
             name_was_remapped: was_remapped,
+            crate_of_origin: 0,
             src: Some(Rc::new(src)),
             start_pos: Pos::from_usize(start_pos),
             end_pos: Pos::from_usize(end_pos),
@@ -204,6 +231,7 @@ impl CodeMap {
     pub fn new_imported_filemap(&self,
                                 filename: FileName,
                                 name_was_remapped: bool,
+                                crate_of_origin: u32,
                                 source_len: usize,
                                 mut file_local_lines: Vec<BytePos>,
                                 mut file_local_multibyte_chars: Vec<MultiByteChar>)
@@ -225,6 +253,7 @@ impl CodeMap {
         let filemap = Rc::new(FileMap {
             name: filename,
             name_was_remapped: name_was_remapped,
+            crate_of_origin: crate_of_origin,
             src: None,
             start_pos: start_pos,
             end_pos: end_pos,
@@ -282,6 +311,8 @@ impl CodeMap {
         let files = self.files.borrow();
         let f = (*files)[idx].clone();
 
+        (self.dep_tracking_callback.borrow())(&f);
+
         match f.lookup_line(pos) {
             Some(line) => Ok(FileMapAndLine { fm: f, line: line }),
             None => Err(f)
@@ -471,6 +502,7 @@ impl CodeMap {
     pub fn get_filemap(&self, filename: &str) -> Option<Rc<FileMap>> {
         for fm in self.files.borrow().iter() {
             if filename == fm.name {
+               (self.dep_tracking_callback.borrow())(&fm);
                 return Some(fm.clone());
             }
         }
@@ -481,6 +513,7 @@ impl CodeMap {
     pub fn lookup_byte_offset(&self, bpos: BytePos) -> FileMapAndBytePos {
         let idx = self.lookup_filemap_idx(bpos);
         let fm = (*self.files.borrow())[idx].clone();
+        (self.dep_tracking_callback.borrow())(&fm);
         let offset = bpos - fm.start_pos;
         FileMapAndBytePos {fm: fm, pos: offset}
     }
@@ -491,6 +524,8 @@ impl CodeMap {
         let files = self.files.borrow();
         let map = &(*files)[idx];
 
+        (self.dep_tracking_callback.borrow())(map);
+
         // The number of extra bytes due to multibyte chars in the FileMap
         let mut total_extra_bytes = 0;
 
@@ -536,7 +571,7 @@ impl CodeMap {
     }
 
     pub fn count_lines(&self) -> usize {
-        self.files.borrow().iter().fold(0, |a, f| a + f.count_lines())
+        self.files().iter().fold(0, |a, f| a + f.count_lines())
     }
 }