From f70ae03b47d57a1eb151f03cfb0f5445fc301400 Mon Sep 17 00:00:00 2001
From: Jakob Stoklund Olesen <jolesen@mozilla.com>
Date: Fri, 31 Mar 2017 15:45:21 -0700
Subject: [PATCH] Skip the Python checks if the Python files haven't changed.

---
 cranelift/test-all.sh | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/cranelift/test-all.sh b/cranelift/test-all.sh
index 6e2ceb2de1..14b712d9b4 100755
--- a/cranelift/test-all.sh
+++ b/cranelift/test-all.sh
@@ -46,8 +46,18 @@ else
     echo "If a newer version of rustfmt is available, update this script."
 fi
 
-banner $(python --version 2>&1)
-$topdir/lib/cretonne/meta/check.sh
+# Check if any Python files have changed since we last checked them.
+tsfile=$topdir/target/meta-checked
+if [ -f $tsfile ]; then
+    needcheck=$(find $topdir/lib/cretonne/meta -name '*.py' -newer $tsfile)
+else
+    needcheck=yes
+fi
+if [ -n "$needcheck" ]; then
+    banner $(python --version 2>&1)
+    $topdir/lib/cretonne/meta/check.sh
+    touch $tsfile
+fi
 
 PKGS="cretonne cretonne-reader cretonne-tools filecheck"
 cd "$topdir"