json: implement -index decode option

3 files changed, 43 insertions, 6 deletions

diff --git a/jim-json.c b/jim-json.c
index 0a47d4d..1b3869c 100644
--- a/jim-json.c
+++ b/jim-json.c
@@ -44,6 +44,7 @@ struct json_state {
 	int need_subst;
 	/* The following are used for -schema */
 	int enable_schema;
+	int enable_index;
 	Jim_Obj *schemaObj;
 	Jim_Obj *schemaTypeObj[JSON_MAX_TYPE];
 };
@@ -183,6 +184,10 @@ json_decode_dump_container(Jim_Interp *interp, struct json_state *state)
 			json_decode_dump_value(interp, state, list);
 		}
 
+		if (state->enable_index && type == JSMN_ARRAY) {
+			Jim_ListAppendElement(interp, list, Jim_NewIntObj(interp, i));
+		}
+
 		if (state->schemaObj && container_type != JSON_LIST) {
 			if (state->tok->type == JSMN_STRING || state->tok->type == JSMN_PRIMITIVE) {
 				json_decode_add_schema_type(interp, state, json_decode_get_type(state->tok, state->json));
@@ -245,8 +250,8 @@ json_decode_dump_value(Jim_Interp *interp, struct json_state *state, Jim_Obj *li
  */
 static int parse_json_decode_options(Jim_Interp *interp, int argc, Jim_Obj *const argv[], struct json_state *state)
 {
-	static const char * const options[] = { "-null", "-schema", NULL };
-	enum { OPT_NULL, OPT_SCHEMA, };
+	static const char * const options[] = { "-index", "-null", "-schema", NULL };
+	enum { OPT_INDEX, OPT_NULL, OPT_SCHEMA, };
 	int i;
 
 	for (i = 1; i < argc - 1; i++) {
@@ -255,6 +260,10 @@ static int parse_json_decode_options(Jim_Interp *interp, int argc, Jim_Obj *cons
 			return JIM_ERR;
 		}
 		switch (option) {
+			case OPT_INDEX:
+				state->enable_index = 1;
+				break;
+
 			case OPT_NULL:
 				i++;
 				Jim_IncrRefCount(argv[i]);
@@ -270,7 +279,7 @@ static int parse_json_decode_options(Jim_Interp *interp, int argc, Jim_Obj *cons
 
 	if (i != argc - 1) {
 		Jim_WrongNumArgs(interp, 1, argv,
-			"?-null nullvalue? ?-schema? json");
+			"?-index? ?-null nullvalue? ?-schema? json");
 		return JIM_ERR;
 	}
 
diff --git a/jim_tcl.txt b/jim_tcl.txt
index 2ad1f25..01c33b4 100644
--- a/jim_tcl.txt
+++ b/jim_tcl.txt
@@ -5371,10 +5371,12 @@ json::decode
 
 The JSON -> Tcl decoder is part of the optional 'json' package.
 
-+*json::decode* ?*-null* 'string'? ?*-schema*? 'json-string'+::
++*json::decode* ?*-index*? ?*-null* 'string'? ?*-schema*? 'json-string'+::
 
-Decodes the given JSON string (must be array or object) into a Tcl data structure. If '+-schema+' is specified, returns a
-list of +'{data schema}'+ where the schema is compatible with `json::encode`. Otherwise just returns the data.
+Decodes the given JSON string (must be array or object) into a Tcl data structure. If '+-index+' is specified,
+decodes JSON arrays as dictionaries with numeric keys. This makes it possible to retrieve data from nested
+arrays and dictionaries with just '+dict get+'. With the option '+-schema+' returns a list of +'{data schema}'+
+where the schema is compatible with `json::encode`. Otherwise just returns the data.
 Decoding is as follows (with schema types listed in parentheses):
 * object -> dict ('obj')
 * array -> list ('mixed' or 'list')
@@ -5393,6 +5395,8 @@ Decoding is as follows (with schema types listed in parentheses):
     {a 1 b 2} {obj a num b num}
     . json::decode -schema {[1, 2, {a:"b", c:false}, "hello"]}
     {1 2 {a b c false} hello} {mixed num num {obj a str c bool} str}
+    . json::decode -index {["foo", "bar"]}
+    {0 foo 1 bar}
 ----
 
 [[BuiltinVariables]]
diff --git a/tests/json.test b/tests/json.test
index 8dfa567..ed73401 100644
--- a/tests/json.test
+++ b/tests/json.test
@@ -99,6 +99,30 @@ test json-2.9 {schema tests} {
 	lindex [json::decode -schema {[{a:1},{b:2}]}] 1
 } {mixed {obj a num} {obj b num}}
 
+
+test json-3.1 {-index array} {
+	json::decode -index \
+		{[null, 1, 2, true, false, "hello"]}
+} {0 null 1 1 2 2 3 true 4 false 5 hello}
+
+test json-3.2 {-index array and object} {
+	json::decode -index \
+		{{"outer": [{"key": "value"}, {"key2": "value2"}]}}
+} {outer {0 {key value} 1 {key2 value2}}}
+
+test json-3.3 {-index array with -schema} {
+	json::decode -index -schema \
+		{[null, 1, 2, true, false, "hello"]}
+} "{0 null 1 1 2 2 3 true 4 false 5 hello}\
+   {mixed num num num bool bool str}"
+
+test json-3.4 {-index array with -schema 2} {
+	json::decode -index -schema \
+		{{"outer": [{"key": "value"}, {"key2": "value2"}]}}
+} "{outer {0 {key value} 1 {key2 value2}}}\
+   {obj outer {mixed {obj key str} {obj key2 str}}}"
+
+
 unset -nocomplain json
 
 test json-encode-1.1 {String with backslashes}  {