Use word-diff when possible when comparing json ui output in tests

If git is present we can rely on git-diff word support to get a much
easier to understand diff.

1 files changed, 10 insertions, 4 deletions

diff --git a/test/run b/test/run
index a26642da..8ce73f2a 100755
--- a/test/run
+++ b/test/run
@@ -136,10 +136,16 @@ fail_ifn() {
   fi
 }
 
-assert_eq() {
+check_json_eq() {
   if [ ! "$1" = "$2" ]; then
     fail_ifn
-    printf "${indent}  ${red}- %s\n${indent}  ${green}+ %s${none}\n" "$1" "$2"
+    if command -v git > /dev/null; then
+        echo "$1" > expected
+        echo "$2" > actual
+        git --no-pager diff --color-words --no-index expected actual
+    else
+        printf "${indent}  ${red}- %s\n${indent}  ${green}+ %s${none}\n" "$1" "$2"
+    fi
   fi
 }
 
@@ -204,7 +210,7 @@ ui_out() {
     while read -r event <&4; do
       if printf %s "$event" | "${arg#-until-}" "$pattern" >/dev/null; then
         if [ $# -ne 0 ]; then
-            assert_eq "$1" "$event"
+            check_json_eq "$1" "$event"
             shift
         fi
         break
@@ -213,7 +219,7 @@ ui_out() {
     ;;
   *)
     read -r event <&4
-    assert_eq "$arg" "$event"
+    check_json_eq "$arg" "$event"
     ;;
   esac
 }