Adding JSONTokener.back() just before throwing JSONException

migueltt · migueltt · commit 7d8353401ad0 · 2017-08-10T19:05:57.000-04:00
This forces JSONTokener.syntaxError(..) to point to the last character of the duplicate key.
diff --git a/JSONObject.java b/JSONObject.java
@@ -232,12 +232,13 @@ public JSONObject(JSONTokener x) throws JSONException {
                 throw x.syntaxError("Expected a ':' after a key");
             }
             
-            // Replace: this.putOnce(key, x.nextValue());
             // Use syntaxError(..) to include error location
             
             if (key != null) {
                 // Check if key exists
             	if (this.opt(key) != null) {
+            		// back one token to point to the last key character
+            		x.back();
                     throw x.syntaxError("Duplicate key \"" + key + "\"");
             	}
                 // Only add value if non-null

Original file line number	Diff line number	Diff line change
`@@ -232,12 +232,13 @@ public JSONObject(JSONTokener x) throws JSONException {`
`232`	`232`	`throw x.syntaxError("Expected a ':' after a key");`
`233`	`233`	`}`
`234`	`234`
`235`		`- // Replace: this.putOnce(key, x.nextValue());`
`236`	`235`	`// Use syntaxError(..) to include error location`
`237`	`236`
`238`	`237`	`if (key != null) {`
`239`	`238`	`// Check if key exists`
`240`	`239`	`if (this.opt(key) != null) {`
	`240`	`+ // back one token to point to the last key character`
	`241`	`+ x.back();`
`241`	`242`	`throw x.syntaxError("Duplicate key \"" + key + "\"");`
`242`	`243`	`}`
`243`	`244`	`// Only add value if non-null`