77 lines
1.5 KiB
JavaScript
77 lines
1.5 KiB
JavaScript
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var untilde = function(str) {
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return str.replace(/~./g, function(m) {
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switch (m) {
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case "~0":
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return "~";
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case "~1":
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return "/";
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}
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throw new Error("Invalid tilde escape: " + m);
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});
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}
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var traverse = function(obj, pointer, value) {
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// assert(isArray(pointer))
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var part = untilde(pointer.shift());
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if(!obj.hasOwnProperty(part)) {
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return null;
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}
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if(pointer.length !== 0) { // keep traversin!
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return traverse(obj[part], pointer, value);
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}
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// we're done
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if(typeof value === "undefined") {
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// just reading
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return obj[part];
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}
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// set new value, return old value
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var old_value = obj[part];
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if(value === null) {
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delete obj[part];
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} else {
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obj[part] = value;
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}
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return old_value;
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}
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var validate_input = function(obj, pointer) {
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if(typeof obj !== "object") {
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throw new Error("Invalid input object.");
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}
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if(pointer === "") {
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return [];
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}
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if(!pointer) {
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throw new Error("Invalid JSON pointer.");
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}
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pointer = pointer.split("/");
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var first = pointer.shift();
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if (first !== "") {
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throw new Error("Invalid JSON pointer.");
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}
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return pointer;
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}
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var get = function(obj, pointer) {
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pointer = validate_input(obj, pointer);
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if (pointer.length === 0) {
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return obj;
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}
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return traverse(obj, pointer);
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}
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var set = function(obj, pointer, value) {
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pointer = validate_input(obj, pointer);
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if (pointer.length === 0) {
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throw new Error("Invalid JSON pointer for set.")
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}
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return traverse(obj, pointer, value);
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}
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exports.get = get
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exports.set = set
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