Improve JSON parser exception message

aspnet · May 15, 2015 · 6b0dc2b · 6b0dc2b
1 parent 5779585
commit 6b0dc2b
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Showing 5 changed files with 29 additions and 26 deletions.
diff --git a/src/Microsoft.Framework.Runtime.Hosting/FileFormatException.cs b/src/Microsoft.Framework.Runtime.Hosting/FileFormatException.cs
@@ -21,6 +21,11 @@ public sealed class FileFormatException : Exception
         public string Path { get; private set; }
         public int Line { get; private set; }
         public int Column { get; private set; }
+
+        public override string ToString()
+        {            
+            return $"{Path}({Line},{Column}): Error: {base.ToString()}";
+        }
 
         internal static FileFormatException Create(Exception exception, string filePath)
         {
@@ -69,7 +74,6 @@ internal static FileFormatException Create(string message, string filePath)
             return result;
         }
 
-
         internal static FileFormatException Create(string message, JsonValue jsonValue)
         {
             var result = new FileFormatException(message)

diff --git a/src/Microsoft.Framework.Runtime.Hosting/Json/JsonBuffer.cs b/src/Microsoft.Framework.Runtime.Hosting/Json/JsonBuffer.cs
@@ -43,7 +43,7 @@ public JsonToken Read()
                 }
             }
 
-            _token.Value = null;
+            _token.Value = ((char)first).ToString();
             _token.Line = _line;
             _token.Column = _column;
 

diff --git a/src/Microsoft.Framework.Runtime.Hosting/Json/JsonDeserializer.cs b/src/Microsoft.Framework.Runtime.Hosting/Json/JsonDeserializer.cs
@@ -69,7 +69,9 @@ private static JsonValue DeserializeInternal(JsonToken next, JsonBuffer buffer)
                 return new JsonNumber(next);
             }
 
-            throw new JsonDeserializerException(JsonDeserializerResource.Format_UnexpectedToken(next.Value, next.Type), next);
+            throw new JsonDeserializerException(JsonDeserializerResource.Format_InvalidTokenExpectation(
+                next.Value, "'{', '[', true, false, null, JSON string, JSON number, or the end of the file"), 
+                next);
         }
 
         private static JsonArray DeserializeArray(JsonToken head, JsonBuffer buffer)

diff --git a/src/Microsoft.Framework.Runtime.Hosting/Json/JsonDeserializerResource.cs b/src/Microsoft.Framework.Runtime.Hosting/Json/JsonDeserializerResource.cs
@@ -7,80 +7,77 @@ internal class JsonDeserializerResource
     {
         internal static string Format_IllegalCharacter(int value)
         {
-            return string.Format("Illegal character {0} {0:X4}.", (char)value, value);
+            return $"Illegal character '{(char)value}' (Unicode hexadecimal {value:X4}).";
         }
 
         internal static string Format_IllegalTrailingCharacterAfterLiteral(int value, string literal)
         {
-            return string.Format("Illegal character {0} ({1:X4}) after the literal name {2}.",
-                (char)value,
-                value,
-                literal);
+            return $"Illegal character '{(char)value}' (Unicode hexadecimal {value:X4}) after the literal name '{literal}'.";
         }
 
         internal static string Format_UnrecognizedLiteral(string literal)
         {
-            return string.Format("Invalid JSON literal. {0} is not legal JSON literal.", literal);
-        }
-
-        internal static string Format_UnexpectedToken(string tokenValue, JsonTokenType type)
-        {
-            return string.Format("Unexpected token, type: {0} value: {1}.", type.ToString(), tokenValue);
+            return $"Invalid JSON literal. Expected literal '{literal}'.";
         }
 
         internal static string Format_DuplicateObjectMemberName(string memberName)
         {
-            return Format_InvalidSyntax("JSON object", string.Format("Duplicate member name {0}.", memberName));
+            return Format_InvalidSyntax("JSON object", $"Duplicate member name '{memberName}'");
         }
 
         internal static string Format_InvalidFloatNumberFormat(string raw)
         {
-            return string.Format("Invalid float number format: {0}", raw);
+            return $"Invalid float number format: {raw}";
         }
 
         internal static string Format_FloatNumberOverflow(string raw)
         {
-            return string.Format("Float number overflow: {0}", raw);
+            return $"Float number overflow: {raw}";
         }
 
         internal static string Format_InvalidSyntax(string syntaxName, string issue)
         {
-            return string.Format("Invalid {0} syntax. {1}.");
+            return $"Invalid {syntaxName} syntax. {issue}.";
         }
 
         internal static string Format_InvalidSyntaxNotExpected(string syntaxName, char unexpected)
         {
-            return string.Format("Invalid {0} syntax. Unexpected '{1}'.", syntaxName, unexpected);
+            return $"Invalid {syntaxName} syntax. Unexpected '{unexpected}'.";
         }
 
         internal static string Format_InvalidSyntaxNotExpected(string syntaxName, string unexpected)
         {
-            return string.Format("Invalid {0} syntax. Unexpected {1}.", syntaxName, unexpected);
+            return $"Invalid {syntaxName} syntax. Unexpected {unexpected}.";
         }
 
         internal static string Format_InvalidSyntaxExpectation(string syntaxName, char expectation)
         {
-            return string.Format("Invalid {0} syntax. Expected '{1}'.", syntaxName, expectation);
+            return $"Invalid {syntaxName} syntax. Expected '{expectation}'.";
         }
 
         internal static string Format_InvalidSyntaxExpectation(string syntaxName, string expectation)
         {
-            return string.Format("Invalid {0} syntax. Expected {1}.", syntaxName, expectation);
+            return $"Invalid {syntaxName} syntax. Expected {expectation}.";
         }
 
         internal static string Format_InvalidSyntaxExpectation(string syntaxName, char expectation1, char expectation2)
         {
-            return string.Format("Invalid {0} syntax. Expected '{1}' or '{2}'.", syntaxName, expectation1, expectation2);
+            return $"Invalid {syntaxName} syntax. Expected '{expectation1}' or '{expectation2}'.";
+        }
+
+        internal static string Format_InvalidTokenExpectation(string tokenValue, string expectation)
+        {
+            return $"Unexpected token '{tokenValue}'. Expected {expectation}.";
         }
 
         internal static string Format_InvalidUnicode(string unicode)
         {
-            return string.Format("Invalid Unicode [{0}]", unicode);
+            return $"Invalid Unicode [{unicode}]";
         }
 
         internal static string Format_UnfinishedJSON(string nextTokenValue)
         {
-            return string.Format("Invalid JSON end. Unprocessed token {0}.", nextTokenValue);
+            return $"Invalid JSON end. Unprocessed token {nextTokenValue}.";
         }
 
         internal static string JSON_OpenString

diff --git a/src/Microsoft.Framework.Runtime/Project.cs b/src/Microsoft.Framework.Runtime/Project.cs
@@ -173,7 +173,7 @@ internal static Project GetProjectFromStream(Stream stream, string projectName,
             if (rawProject == null)
             {
                 throw FileFormatException.Create(
-                    "The JSON file can't be deserialized to a Json object.",
+                    "The JSON file can't be deserialized to a JSON object.",
                     projectPath);
             }