Add some debug logging if tar fails

Summary: This is to help debug the root cause of https://github.com/facebook/react-native/issues/14423

Reviewed By: javache

Differential Revision: D5254713

fbshipit-source-id: 1ca90205144b3a069d927ba6636f0ef0138b51a0

scripts/ios-install-third-party.sh

@@ -1,10 +1,5 @@
 #!/bin/bash
 
-#boostdir="`node ./node_modules/boost-lib/bin/boost-lib download -V 1.63`"
-#cd "$boostdir"
-#./bootstrap.sh
-#./b2 headers
-
 set -e
 
 cachedir="$HOME/.rncache"
@@ -23,8 +18,12 @@ function fetch_and_unpack () {
     if [ ! -d "third-party/$dir" ]; then
         (cd third-party;
          echo Unpacking "$cachedir/$file"...
-         tar zxf "$cachedir/$file"
-
+         if ! tar zxf "$cachedir/$file"; then
+             echo "Unpacking '$cachedir/$file' failed.  Debug info:" 2>&1
+             ls -l "$cachedir/$file" 2>&1
+             shasum ~/.rncache/boost_1_63_0.tar.gz 2>&1
+             exit 1
+         fi
          cd "$dir"
          eval "${cmd:-true}")
     fi