Disallow trailing commas.

Clean up EXPECTED messages.

parse.sh

@@ -19,51 +19,58 @@ parse_array () {
   local index=0
   local ary=''
   read -r token
-  while true;
-  do
-    case "$token" in
-      ']') break ;;
-    esac
-    parse_value "$1" "$index"
-    let index=$index+1
-    ary="$ary""$value" 
-    read -r token
-    case "$token" in
-      ']') break ;;
-      ',') ary="$ary", ;;
-      *) throw "EXPECTED ] or , GOT ${token:-EOF}" ;;
-    esac
-    read -r token
-  done
+  case "$token" in
+    ']') ;;
+    *)
+      while :
+      do
+        parse_value "$1" "$index"
+        let index=$index+1
+        ary="$ary""$value" 
+        read -r token
+        case "$token" in
+          ']') break ;;
+          ',') ary="$ary," ;;
+          *) throw "EXPECTED , or ] GOT ${token:-EOF}" ;;
+        esac
+        read -r token
+      done
+      ;;
+  esac
   value=`printf '[%s]' $ary`
 }
 
 parse_object () {
   local key
   local obj=''
   read -r token
-  while :
-  do
-    case "$token" in
-      '}') break ;;
-      '"'*'"') key=$token ;;
-      *) throw "EXPECTED STRING, GOT ${token:-EOF}" ;;
-    esac
-    read -r token
-    case "$token" in
-      ':') ;;
-      *) throw "EXPECTED COLON, GOT ${token:-EOF}" ;;
-    esac
-    read -r token
-    parse_value "$1" "$key"
-    obj="$obj$key:$value"        
-    read -r token
-    case "$token" in
-      '}') break;;
-      ',') obj="$obj,"; read -r token ;;
-      *) throw "EXPECTED , or }, but got ${token:-EOF}" ;;
-    esac
-  done
+  case "$token" in
+    '}') ;;
+    *)
+      while :
+      do
+        case "$token" in
+          '"'*'"') key=$token ;;
+          *) throw "EXPECTED string GOT ${token:-EOF}" ;;
+        esac
+        read -r token
+        case "$token" in
+          ':') ;;
+          *) throw "EXPECTED : GOT ${token:-EOF}" ;;
+        esac
+        read -r token
+        parse_value "$1" "$key"
+        obj="$obj$key:$value"        
+        read -r token
+        case "$token" in
+          '}') break ;;
+          ',') obj="$obj," ;;
+          *) throw "EXPECTED , or } GOT ${token:-EOF}" ;;
+        esac
+        read -r token
+      done
+    ;;
+  esac
   value=`printf '{%s}' "$obj"`
 }
 
@@ -73,7 +80,7 @@ parse_value () {
     '{') parse_object "$jpath" ;;
     '[') parse_array  "$jpath" ;;
     # At this point, the only valid single-character tokens are digits.
-    ''|[^0-9]) throw "EXPECTED value, GOT ${token:-EOF}" ;;
+    ''|[^0-9]) throw "EXPECTED value GOT ${token:-EOF}" ;;
     *) value=$token ;;
   esac
   printf "[%s]\t%s\n" "$jpath" "$value"
@@ -85,6 +92,6 @@ parse () {
   read -r token
   case "$token" in
     '') ;;
-    *) throw "EXPECTED EOF, GOT $token" ;;
+    *) throw "EXPECTED EOF GOT $token" ;;
   esac
 }

test/invalid/trailing_array_comma.json

@@ -0,0 +1 @@
+[1,2,3,]

test/invalid/trailing_object_comma.json

@@ -0,0 +1 @@
+{"a":1,"b":2,"c":3,}