pretty=expanded should expand mod declarations

src/libsyntax/parse/parser.rs

@@ -6288,10 +6288,9 @@ impl<'a> Parser<'a> {
                 // This mod is in an external file. Let's go get it!
                 let ModulePathSuccess { path, directory_ownership, warn } =
                     self.submod_path(id, &outer_attrs, id_span)?;
-                let (mut module, mut attrs) =
+                let (module, mut attrs) =
                     self.eval_src_mod(path, directory_ownership, id.to_string(), id_span)?;
                 // Record that we fetched the mod from an external file
-                module.inline = false;
                 if warn {
                     let attr = Attribute {
                         id: attr::mk_attr_id(),
@@ -6530,7 +6529,8 @@ impl<'a> Parser<'a> {
         p0.cfg_mods = self.cfg_mods;
         let mod_inner_lo = p0.span;
         let mod_attrs = p0.parse_inner_attributes()?;
-        let m0 = p0.parse_mod_items(&token::Eof, mod_inner_lo)?;
+        let mut m0 = p0.parse_mod_items(&token::Eof, mod_inner_lo)?;
+        m0.inline = false;
         self.sess.included_mod_stack.borrow_mut().pop();
         Ok((m0, mod_attrs))
     }

src/libsyntax/print/pprust.rs

@@ -61,6 +61,7 @@ pub struct State<'a> {
     cur_cmnt: usize,
     boxes: Vec<pp::Breaks>,
     ann: &'a (dyn PpAnn+'a),
+    is_expanded: bool
 }
 
 fn rust_printer<'a>(writer: Box<dyn Write+'a>, ann: &'a dyn PpAnn) -> State<'a> {
@@ -72,6 +73,7 @@ fn rust_printer<'a>(writer: Box<dyn Write+'a>, ann: &'a dyn PpAnn) -> State<'a>
         cur_cmnt: 0,
         boxes: Vec::new(),
         ann,
+        is_expanded: false
     }
 }
 
@@ -133,14 +135,17 @@ impl<'a> State<'a> {
             // If the code is post expansion, don't use the table of
             // literals, since it doesn't correspond with the literals
             // in the AST anymore.
-            if is_expanded { None } else { Some(lits) })
+            if is_expanded { None } else { Some(lits) },
+            is_expanded
+        )
     }
 
     pub fn new(cm: &'a SourceMap,
                out: Box<dyn Write+'a>,
                ann: &'a dyn PpAnn,
                comments: Option<Vec<comments::Comment>>,
-               literals: Option<Vec<comments::Literal>>) -> State<'a> {
+               literals: Option<Vec<comments::Literal>>,
+               is_expanded: bool) -> State<'a> {
         State {
             s: pp::mk_printer(out, DEFAULT_COLUMNS),
             cm: Some(cm),
@@ -149,6 +154,7 @@ impl<'a> State<'a> {
             cur_cmnt: 0,
             boxes: Vec::new(),
             ann,
+            is_expanded: is_expanded
         }
     }
 }
@@ -1261,7 +1267,8 @@ impl<'a> State<'a> {
                 self.head(&visibility_qualified(&item.vis, "mod"))?;
                 self.print_ident(item.ident)?;
 
-                if _mod.inline {
+                if _mod.inline || self.is_expanded {
+                    println!("Going to print inline anyway");
                     self.nbsp()?;
                     self.bopen()?;
                     self.print_mod(_mod, &item.attrs)?;

src/test/pretty/issue_12590_c.pp

@@ -0,0 +1,24 @@
+// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// pp-exact:issue_12590_c.pp
+// pretty-mode:expanded
+
+// The next line should be expanded
+
+mod issue_12590_b {
+
+
+  fn b() { }
+
+  fn main() { }
+}
+
+fn main() { }

src/test/pretty/issue_12590_c.rs

@@ -0,0 +1,18 @@
+// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// pp-exact:issue_12590_c.pp
+// pretty-mode:expanded
+
+// The next line should be expanded
+
+mod issue_12590_b;
+
+fn main() { }