Move nodejs detection into bootstrap

This avoids issues with mingw path conversions.

configure

@@ -637,7 +637,6 @@ valopt datadir "${CFG_PREFIX}/share" "install data"
 valopt infodir "${CFG_PREFIX}/share/info" "install additional info"
 valopt llvm-root "" "set LLVM root"
 valopt python "" "set path to python"
-valopt nodejs "" "set path to nodejs"
 valopt jemalloc-root "" "set directory where libjemalloc_pic.a is located"
 valopt build "${DEFAULT_BUILD}" "GNUs ./configure syntax LLVM build triple"
 valopt android-cross-path "" "Android NDK standalone path (deprecated)"
@@ -754,9 +753,6 @@ if [ $(echo $python_version | grep -c '^Python 2\.7') -ne 1 ]; then
     err "Found $python_version, but Python 2.7 is required"
 fi
 
-# Checking for node, but not required
-probe CFG_NODEJS nodejs node
-
 # If we have no git directory then we are probably a tarball distribution
 # and shouldn't attempt to load submodules
 if [ ! -e ${CFG_SRC_DIR}.git ]

src/bootstrap/config.rs

@@ -396,9 +396,6 @@ impl Config {
                     self.rustc = Some(PathBuf::from(value).join("bin/rustc"));
                     self.cargo = Some(PathBuf::from(value).join("bin/cargo"));
                 }
-                "CFG_NODEJS" if value.len() > 0 => {
-                    self.nodejs = Some(PathBuf::from(value));
-                }
                 _ => {}
             }
         }

src/bootstrap/sanity.rs

@@ -40,17 +40,23 @@ pub fn check(build: &mut Build) {
             panic!("PATH contains invalid character '\"'");
         }
     }
-    let mut need_cmd = |cmd: &OsStr| {
-        if !checked.insert(cmd.to_owned()) {
-            return
-        }
+    let have_cmd = |cmd: &OsStr| {
         for path in env::split_paths(&path).map(|p| p.join(cmd)) {
             if fs::metadata(&path).is_ok() ||
                fs::metadata(path.with_extension("exe")).is_ok() {
-                return
+                return Some(path);
             }
         }
-        panic!("\n\ncouldn't find required command: {:?}\n\n", cmd);
+        return None;
+    };
+
+    let mut need_cmd = |cmd: &OsStr| {
+        if !checked.insert(cmd.to_owned()) {
+            return
+        }
+        if have_cmd(cmd).is_none() {
+            panic!("\n\ncouldn't find required command: {:?}\n\n", cmd);
+        }
     };
 
     // If we've got a git directory we're gona need git to update
@@ -75,8 +81,13 @@ pub fn check(build: &mut Build) {
 
     need_cmd("python".as_ref());
 
-    // If a manual nodejs was added to the config,
-    // of if a nodejs install is detected through config, use it.
+    // Look for the nodejs command, needed for emscripten testing
+    if let Some(node) = have_cmd("node".as_ref()) {
+        build.config.nodejs = Some(node);
+    } else if let Some(node) = have_cmd("nodejs".as_ref()) {
+        build.config.nodejs = Some(node);
+    }
+
     if let Some(ref s) = build.config.nodejs {
         need_cmd(s.as_ref());
     }