Stop traversal past scalar JSON values

bj-1line.sh

@@ -1,2 +1,2 @@
 # (C) Isaac Freeman (memotype@gmail.com). See https://github.com/memotype/bj.sh
-bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;rd(){ l=$c;IFS= read -rN1 c;};pr(){ printf %s "${o[@]}";};st(){ p=$1;[[ $p ]]||o=();while rd;do [[ $p&&! $q ]]&&o+=("$l");case $c in \\)rd||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ $p ]]||o+=("$c");;esac;done;};co(){ n= b=1;while rd;do [[ $q ]]||o+=("$l");case $c in \")[[ $1||! $q ]]&&st 1||{ st;k=$(pr);};;[|{)((b++));;]|\})((--b))||{ [[ $q ]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&$q&&$k = "$q" ]]&&break;;,)((0$1&&b == 1))&&{ ((n++));[[ $n = "$q" ]]&&break;};;esac;done;};for q in "$@" "";do shift&&[[ ! $q ]]&&return 2;x=0;o=();while rd;do case $c in [[:space:]])! :;;\")st;;[tfn0-9-])while o+=("$c")&&rd&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done;;{)co;;[)[[ $q = 0 ]]||co 1;;*)return 2;;esac&&x=1&&break;done;done;pr;((x));)
+bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;r(){ l=$c;IFS= read -rN1 c;};p(){ printf %s "${o[@]}";};s(){ p=$1;[[ $p ]]||o=();while r;do [[ $p&&! $q ]]&&o+=("$l");case $c in \\)r||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ $p ]]||o+=("$c");;esac;done;};co(){ n= b=1;while r;do [[ $q ]]||o+=("$l");case $c in \")[[ $1||! $q ]]&&s 1||{ s;k=$(p);};;[|{)((b++));;]|\})((--b))||{ [[ $q ]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&$q&&$k = "$q" ]]&&break;;,)((0$1&&b==1))&&[[ $q = $((++n)) ]]&&break;;esac;done;};for q in "$@" "";do shift&&[[ ! $q ]]&&return 2;x=0;o=();while r;do case $q$c in *[[:space:]])! :;;\")s;;[tfn0-9-])while o+=("$c")&&r&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done;;*{)co;;*[)[[ $q = 0 ]]||co 1;;?)return 2;;*)return 1;;esac&&x=1&&break;done;done;p;((x));)

bj-80-col.sh

@@ -1,11 +1,11 @@
 # (C) Isaac Freeman (memotype@gmail.com). See https://github.com/memotype/bj.sh
-bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;rd(){ l=$c;IFS= read -rN1 c;};pr(){ \
-printf %s "${o[@]}";};st(){ p=$1;[[ $p ]]||o=();while rd;do [[ $p&&! $q ]]&&o+=\
-("$l");case $c in \\)rd||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ \
-$p ]]||o+=("$c");;esac;done;};co(){ n= b=1;while rd;do [[ $q ]]||o+=("$l")
-case $c in \")[[ $1||! $q ]]&&st 1||{ st;k=$(pr);};;[|{)((b++));;]|\})((--b))||
-{ [[ $q ]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&$q&&$k = "$q" ]]&&break;;,)
-((0$1&&b == 1))&&{ ((n++));[[ $n = "$q" ]]&&break;};;esac;done;};for q in "$@" \
-"";do shift&&[[ ! $q ]]&&return 2;x=0;o=();while rd;do case $c in [[:space:]])
-! :;;\")st;;[tfn0-9-])while o+=("$c")&&rd&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done;;
-{)co;;[)[[ $q = 0 ]]||co 1;;*)return 2;;esac&&x=1&&break;done;done;pr;((x));)
+bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;r(){ l=$c;IFS= read -rN1 c;};p(){ \
+printf %s "${o[@]}";};s(){ p=$1;[[ $p ]]||o=();while r;do [[ $p&&! $q ]]&&o+=(\
+"$l");case $c in \\)r||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ \
+$p ]]||o+=("$c");;esac;done;};co(){ n= b=1;while r;do [[ $q ]]||o+=("$l");case \
+$c in \")[[ $1||! $q ]]&&s 1||{ s;k=$(p);};;[|{)((b++));;]|\})((--b))||{ [[ $q \
+]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&$q&&$k = "$q" ]]&&break;;,)((0$1&&
+b==1))&&[[ $q = $((++n)) ]]&&break;;esac;done;};for q in "$@" "";do shift&&[[ \
+! $q ]]&&return 2;x=0;o=();while r;do case $q$c in *[[:space:]])! :;;\")s;;
+[tfn0-9-])while o+=("$c")&&r&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done;;*{)co;;*[)[[ \
+$q = 0 ]]||co 1;;?)return 2;;*)return 1;;esac&&x=1&&break;done;done;p;((x));)

bj-90-col.sh

@@ -1,10 +1,10 @@
 # (C) Isaac Freeman (memotype@gmail.com). See https://github.com/memotype/bj.sh
-bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;rd(){ l=$c;IFS= read -rN1 c;};pr(){ printf %s \
-"${o[@]}";};st(){ p=$1;[[ $p ]]||o=();while rd;do [[ $p&&! $q ]]&&o+=("$l");case $c in \\)
-rd||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ $p ]]||o+=("$c");;esac;done;}
-co(){ n= b=1;while rd;do [[ $q ]]||o+=("$l");case $c in \")[[ $1||! $q ]]&&st 1||{ st;k\
-=$(pr);};;[|{)((b++));;]|\})((--b))||{ [[ $q ]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&
-$q&&$k = "$q" ]]&&break;;,)((0$1&&b == 1))&&{ ((n++));[[ $n = "$q" ]]&&break;};;esac;done
-};for q in "$@" "";do shift&&[[ ! $q ]]&&return 2;x=0;o=();while rd;do case $c in \
-[[:space:]])! :;;\")st;;[tfn0-9-])while o+=("$c")&&rd&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done
-;;{)co;;[)[[ $q = 0 ]]||co 1;;*)return 2;;esac&&x=1&&break;done;done;pr;((x));)
+bj()([[ $1 = - ]]||exec<<<"$1";shift;c=;r(){ l=$c;IFS= read -rN1 c;};p(){ printf %s \
+"${o[@]}";};s(){ p=$1;[[ $p ]]||o=();while r;do [[ $p&&! $q ]]&&o+=("$l");case $c in \\)r\
+||break;[[ $p&&$q ]]||o+=("$l${c::!p}");;\")break;;*)[[ $p ]]||o+=("$c");;esac;done;};co\
+(){ n= b=1;while r;do [[ $q ]]||o+=("$l");case $c in \")[[ $1||! $q ]]&&s 1||{ s;k=$(p);}
+;;[|{)((b++));;]|\})((--b))||{ [[ $q ]]&&exit 1;o+=("$c");break;};;:)[[ $1$b = 1&&$q&&$k \
+= "$q" ]]&&break;;,)((0$1&&b==1))&&[[ $q = $((++n)) ]]&&break;;esac;done;};for q in "$@" \
+"";do shift&&[[ ! $q ]]&&return 2;x=0;o=();while r;do case $q$c in *[[:space:]])! :;;\")s
+;;[tfn0-9-])while o+=("$c")&&r&&[[ $c =~ [-+.0-9Ea-z] ]];do :;done;;*{)co;;*[)[[ $q = 0 \
+]]||co 1;;?)return 2;;*)return 1;;esac&&x=1&&break;done;done;p;((x));)

bj.sh

@@ -18,30 +18,30 @@ bj() (
   c=
 
   # Read a character
-  rd() {
+  r() {
     l=$c
     IFS= read -rN1 c
   }
 
   # Join the characters in the $o array
-  pr() {
+  p() {
     # Using ':' with arguments is nice for 'bash -x' debugging
-    : : "=== pr()"
+    : : "=== p()"
     printf %s "${o[@]}"
   }
 
 
   # Scan strings, saving to $o unless navigation only needs to skip them.
-  st() {
-    : : "=== st()"
+  s() {
+    : : "=== s()"
     p=$1
     [[ $p ]] || o=()
-    while rd; do
+    while r; do
       : : "--- lc=$l$c="
       [[ $p && ! $q ]] && o+=("$l")
       case $c in
         \\)
-          rd || break
+          r || break
           # Skip while navigating. Otherwise include $c only when capturing.
           [[ $p && $q ]] || o+=("$l${c::!p}")
         ;;
@@ -55,11 +55,11 @@ bj() (
   co() {
     : : "=== co()"
     n= b=1
-    while rd; do
+    while r; do
       : : "--- l=$l= c=$c= q=$q= b=$b= ---"
       [[ $q ]] || o+=("$l")
       case $c in
-        \") [[ $1 || ! $q ]] && st 1 || { st; k=$(pr); } ;;
+        \") [[ $1 || ! $q ]] && s 1 || { s; k=$(p); } ;;
         [|{) ((b++)) ;; # ]) <- fix vim syntax
         ]|\})
           ((--b)) || {
@@ -73,10 +73,9 @@ bj() (
         # Found the key, just stop and let the main loop parse from here.
         :) [[ $1$b = 1 && $q && $k = "$q" ]] && break ;;
         ,)
-          ((0$1 && b == 1)) && {
-            ((n++))
-            [[ $n = "$q" ]] && break
-          }
+          ((0$1 && b==1)) \
+            && [[ $q = $((++n)) ]] \
+            && break
         ;;
       esac
     done
@@ -89,26 +88,28 @@ bj() (
     x=0
     : : "--- q=$q"
     o=()
-    while rd; do
+    while r; do
       : : "mn --- l=$l c=$c"
-      case $c in
-        [[:space:]]) ! : ;;
-        \") st ;;
+      # Prefix with $q so scalar cases only match during final output.
+      case $q$c in
+        *[[:space:]]) ! : ;;
+        \") s ;;
         [tfn0-9-])
           while o+=("$c") \
-              && rd \
-              && [[ $c =~ [-+.0-9Ea-z] ]]
+            && r \
+            && [[ $c =~ [-+.0-9Ea-z] ]]
           do :;done
         ;;
-        {) co ;;
-        [) [[ $q = 0 ]] || co 1 ;; #])
-        *) return 2 ;;
+        *{) co ;;
+        *[) [[ $q = 0 ]] || co 1 ;; #])
+        ?) return 2 ;;
+        *) return 1 ;;
       esac && x=1 && break
     done
   done
 
   # Print whatever we last stored in $o
-  pr
+  p
 
   ((x))
 )

test.sh

@@ -130,6 +130,22 @@ runtest top '{"target":"top","outer":{"target":"nested"}}' target
 runtest direct \
   '{"level":{"child":{"target":"nested"},"target":"direct"}}' level target
 
+# Traversal must stop when a selected value is a scalar.
+runteststatus 1 '' '{"a":"x","b":"y"}' a extra
+runteststatus 1 '' '{"b":"y","a":"x"}' a extra
+runteststatus 1 '' '{"a":1,"b":2}' a extra
+runteststatus 1 '' '{"b":2,"a":1}' a extra
+runteststatus 1 '' '{"a":true,"b":false}' a extra
+runteststatus 1 '' '{"b":false,"a":true}' a extra
+runteststatus 1 '' '{"a":false,"b":true}' a extra
+runteststatus 1 '' '{"b":true,"a":false}' a extra
+runteststatus 1 '' '{"a":null,"b":0}' a extra
+runteststatus 1 '' '{"b":0,"a":null}' a extra
+runteststatus 1 '' '[1,2]' 0 extra
+runteststatus 1 '' '[1,2]' 1 extra
+runteststatus 1 '' '{"outer":{"a":1,"b":2}}' outer a extra
+runteststatus 1 '' '{"a":1,"b":2}' a extra more
+
 # Numbers tests
 runtest "4.2e10" '[0, -1, 4.2e10]' 2
 runtest "-1" '[0, -1, 4.2e10]' 1
@@ -230,6 +246,17 @@ runtest hit \
   '[0,1,2,3,4,5,6,7,8,9,{"result":"hit"}]' 10 result
 runtest hit '[{},[],{"result":"hit"}]' 2 result
 
+# Empty caller query terms are unsupported and fail when reached.
+runteststatus 2 '' '{"":42}' ''
+runteststatus 2 '' '{"outer":{"":"value"}}' outer ''
+runteststatus 2 '' '{"outer":{"leaf":1}}' '' outer
+runteststatus 2 '' '{"outer":{"leaf":1}}' outer '' leaf
+runteststatus 2 '' '{"outer":{"leaf":1}}' outer leaf ''
+runteststatus 1 '' '{"outer":{"leaf":1}}' missing ''
+runtest 7 '{"":42,"normal":7}' normal
+runtest '{"":42}' '{"":42}'
+runtest '' '{"value":""}' value
+
 # Representative Kubernetes-shaped data used by build and shell automation
 kubernetes_json='{"items":[{"metadata":{"name":"api","annotations":{"example.com/config":"line1\nline2"}},"spec":{"nodeName":null,"containers":[{"name":"app","env":[{"name":"MODE","value":""}]}]}}]}'
 runtest api "$kubernetes_json" items 0 metadata name