From 3fb497c8c860cb286ed59fa49bc1796086196697 Mon Sep 17 00:00:00 2001
From: Lzu Tao <taolzu@gmail.com>
Date: Mon, 3 Jun 2019 09:23:15 +0700
Subject: [PATCH] Do not install rustup-toolchain if it is in PATH

---
 setup-toolchain.sh | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/setup-toolchain.sh b/setup-toolchain.sh
index f8d764b613271..c1c8366bf5e76 100755
--- a/setup-toolchain.sh
+++ b/setup-toolchain.sh
@@ -1,9 +1,12 @@
 #!/bin/bash
 # Set up the appropriate rustc toolchain
 
-cd $(dirname $0)
+cd "$(dirname "$0")"
+
+if ! command -v rustup-toolchain-install-master > /dev/null; then
+  cargo install rustup-toolchain-install-master --debug
+fi
 
-cargo install rustup-toolchain-install-master --debug || echo "rustup-toolchain-install-master already installed"
 RUSTC_HASH=$(git ls-remote https://github.com/rust-lang/rust.git master | awk '{print $1}')
-rustup-toolchain-install-master -f -n master $RUSTC_HASH
+rustup-toolchain-install-master -f -n master "$RUSTC_HASH"
 rustup override set master