Check if out-dir exists before compiling / closes #12865

src/librustc/lib.rs

@@ -286,8 +286,41 @@ pub fn run_compiler(args: &[~str]) {
 
     let sopts = d::build_session_options(matches);
     let sess = d::build_session(sopts, input_file_path);
+    // get the output dir, if there is one
+    // make sure that the directory structure
+    // exists, e.g. if -out-dir is ./foo/bar/baz, each needs to exist
+    // otherwise error out early
     let odir = matches.opt_str("out-dir").map(|o| Path::new(o));
+    match odir {
+        Some(ref odir) => {
+            if !odir.exists() {
+                d::early_error(format!("output directory {} does not exist",
+                               odir.display()))
+            }
+            // if it exists, is it a file?
+            if !odir.is_dir() {
+                d::early_error(format!("specified output directory {} is not a directory",
+                               odir.display()))
+            }
+        }
+        None => {/* continue */ }
+    }
     let ofile = matches.opt_str("o").map(|o| Path::new(o));
+    match ofile {
+        Some(ref ofile) => {
+            // does the directory for -o exist?
+            if !ofile.dir_path().exists() {
+                d::early_error(format!("specified output location's directory {} does not exist",
+                                       ofile.display()))
+            }
+            // does a file exist at -o and is it a directory?
+            if ofile.is_dir() {
+                d::early_error(format!("specified output location {} is a directory",
+                                       ofile.display()))
+            }
+        }
+        None => {/* continue */ }
+    }
     let cfg = d::build_configuration(&sess);
     let pretty = matches.opt_default("pretty", "normal").map(|a| {
         d::parse_pretty(&sess, a)

src/test/run-make/rustc-outfile-error/Makefile

@@ -0,0 +1,5 @@
+-include ../tools.mk
+
+all:
+	$(RUSTCNOARGS) foo.rs -o ./baz/bar.out 2>&1 | grep "error: specified output location's directory baz/bar.out does not exist"
+	$(RUSTCNOARGS) foo.rs -o . 2>&1| grep "error: specified output location . is a directory"

src/test/run-make/rustc-outfile-error/foo.rs

@@ -0,0 +1,11 @@
+// Copyright 2014 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.
+
+pub fn foo() {}

src/test/run-make/rustc-output-dir-error/Makefile

@@ -0,0 +1,5 @@
+-include ../tools.mk
+
+all:
+	$(RUSTCNOARGS) foo.rs --out-dir ./baz/bar 2>&1 | grep "error: output directory baz/bar does not exist"
+	$(RUSTCNOARGS) foo.rs --out-dir ./foo.rs 2>&1 | grep "error: specified output directory foo.rs is not a directory"

src/test/run-make/rustc-output-dir-error/foo.rs

@@ -0,0 +1,11 @@
+// Copyright 2014 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.
+
+pub fn foo() {}

src/test/run-make/tools.mk

@@ -1,6 +1,7 @@
 export LD_LIBRARY_PATH:=$(TMPDIR):$(LD_LIBRARY_PATH)
 export DYLD_LIBRARY_PATH:=$(TMPDIR):$(DYLD_LIBRARY_PATH)
 
+RUSTCNOARGS := $(RUSTC)
 RUSTC := $(RUSTC) --out-dir $(TMPDIR) -L $(TMPDIR)
 CC := $(CC) -L $(TMPDIR)