Rollup merge of #63525 - matklad:centraliza-file-loading, r=petrochenkov

Make sure that all file loading happens via SourceMap

That way, callers don't need to repeat "let's add this to sm manually
for tracking dependencies" trick.

It should make it easier to switch to using `FileLoader` for binary
files in the future as well

cc #62948

r? @petrochenkov

1 files changed, 5 insertions, 8 deletions

diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index e7deadbc9a0..dac402921b9 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -25,7 +25,6 @@ use syntax_pos::{Span, DUMMY_SP, FileName};
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
-use std::fs;
 use std::io::ErrorKind;
 use std::{iter, mem};
 use std::ops::DerefMut;
@@ -1241,13 +1240,11 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
                     }
 
                     let filename = self.cx.resolve_path(&*file.as_str(), it.span());
-                    match fs::read_to_string(&filename) {
-                        Ok(src) => {
-                            let src_interned = Symbol::intern(&src);
-
-                            // Add this input file to the code map to make it available as
-                            // dependency information
-                            self.cx.source_map().new_source_file(filename.into(), src);
+                    match self.cx.source_map().load_file(&filename) {
+                        Ok(source_file) => {
+                            let src = source_file.src.as_ref()
+                                .expect("freshly loaded file should have a source");
+                            let src_interned = Symbol::intern(src.as_str());
 
                             let include_info = vec![
                                 ast::NestedMetaItem::MetaItem(