Add fuzz test for double parsing

Also fix bug in parsing of decimal nums equal to ints
molsonkiko · Nov 9, 2024 · a7fef1c · a7fef1c
1 parent a40137e
commit a7fef1c
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Showing 5 changed files with 88 additions and 63 deletions.
diff --git a/JsonToolsNppPlugin/JSONTools/JNode.cs b/JsonToolsNppPlugin/JSONTools/JNode.cs
@@ -415,7 +415,8 @@ public static string DoubleToString(double d)
         {
             string dubstring = d.ToString(DOT_DECIMAL_SEP);
             int indexOfE = dubstring.IndexOf('E');
-            if (d == Math.Round(d) && !(d > long.MaxValue || d < long.MinValue) && indexOfE < 0)
+            bool isValidLong = d == Math.Round(d) && !(d > long.MaxValue || d < long.MinValue);
+            if (isValidLong && indexOfE < 0)
             {
                 // add ending ".0" to distinguish doubles equal to integers from actual integers
                 // unless they use exponential notation, in which case you mess things up
@@ -432,7 +433,8 @@ public static string DoubleToString(double d)
                     return dubstring; // default string representation has all necessary precision
             }
             catch { }
-            return d.ToString("G17", DOT_DECIMAL_SEP); // we need to use a string representation that retains as much precision as possible
+            string d17 = d.ToString("G17", DOT_DECIMAL_SEP); // we need to use a string representation that retains as much precision as possible
+            return (isValidLong && d17.IndexOf('E') < 0) ? d17 + ".0" : d17;
         }
 
         /// <summary>

diff --git a/JsonToolsNppPlugin/Properties/AssemblyInfo.cs b/JsonToolsNppPlugin/Properties/AssemblyInfo.cs
@@ -28,5 +28,5 @@
 //      Build Number
 //      Revision
 //
-[assembly: AssemblyVersion("8.1.0.15")]
-[assembly: AssemblyFileVersion("8.1.0.15")]
+[assembly: AssemblyVersion("8.1.0.16")]
+[assembly: AssemblyFileVersion("8.1.0.16")]
diff --git a/JsonToolsNppPlugin/Tests/Benchmarker.cs b/JsonToolsNppPlugin/Tests/Benchmarker.cs
@@ -183,7 +183,7 @@ private static bool BenchmarkParser(string jsonstr, int numTrials, JsonParser js
             return true;
         }
 
-        public static bool BenchmarkParseAndFormatDoubles(int numTrials, int arraySize)
+        public static bool BenchmarkAndFuzzParseAndFormatDoubles(int numTrials, int arraySize)
         {
             var parser = new JsonParser();
             Stopwatch watch = new Stopwatch();
@@ -204,11 +204,11 @@ public static bool BenchmarkParseAndFormatDoubles(int numTrials, int arraySize)
                     return true;
                 }
                 numArrPreview = numArrayStr.Length <= 200 ? numArrayStr : numArrayStr.Substring(0, 200) + "...";
-                JNode numArrayNode = new JNode();
+                JArray numArray = new JArray();
                 try
                 {
                     watch.Start();
-                    numArrayNode = parser.Parse(numArrayStr);
+                    numArray = (JArray)parser.Parse(numArrayStr);
                     watch.Stop();
                     ticksToParse[ii] = watch.ElapsedTicks;
                     watch.Reset();
@@ -221,7 +221,7 @@ public static bool BenchmarkParseAndFormatDoubles(int numTrials, int arraySize)
                 try
                 {
                     watch.Start();
-                    numArrayDumped = numArrayNode.ToString();
+                    numArrayDumped = numArray.ToString();
                     watch.Stop();
                     ticksToDump[ii] = watch.ElapsedTicks;
                     watch.Reset();
@@ -231,6 +231,29 @@ public static bool BenchmarkParseAndFormatDoubles(int numTrials, int arraySize)
                     Npp.AddLine($"While compressing the JSON array made by parsing \"{numArrPreview}\", got exception {ex}");
                     return true;
                 }
+                try
+                {
+                    // verify that all doubles in numArray round-trip to the same value when parsing numArrayDumped
+                    JArray numArrayFromDumped = (JArray)parser.Parse(numArrayDumped);
+                    var badValues = new List<double>();
+                    for (int jj = 0; jj < numArray.Length; jj++)
+                    {
+                        double val = (double)numArray[jj].value;
+                        double reloaded = (double)numArrayFromDumped[jj].value;
+                        if (val != reloaded)
+                            badValues.Add(val);
+                    }
+                    if (badValues.Count > 0)
+                    {
+                        Npp.AddLine($"The following doubles did not round-trip:\r\n" + string.Join(", ", badValues.Select(x => x.ToString(JNode.DOT_DECIMAL_SEP))));
+                        return true;
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Npp.AddLine($"While parsing the JSON array made by dumping numArray, and comparing the re-parsed array to numArray, got exception {ex}");
+                    return true;
+                }
             }
             (double mean, double sd) = GetMeanAndSd(ticksToParse);
             Npp.AddLine($"To parse arrays of {arraySize} non-integer numbers (representative length = {numArrayStr.Length}, representative example preview: \"{numArrPreview}\") " +

diff --git a/JsonToolsNppPlugin/Tests/TestRunner.cs b/JsonToolsNppPlugin/Tests/TestRunner.cs
@@ -112,8 +112,8 @@ public static async Task RunAll()
                     "JsonParser performance",
                     true, false
                 ),
-                (() => Benchmarker.BenchmarkParseAndFormatDoubles(32, 5000),
-                    "performance of parsing and dumping arrays of non-integer numbers",
+                (() => Benchmarker.BenchmarkAndFuzzParseAndFormatDoubles(32, 5000),
+                    "performance and correctness of parsing and dumping arrays of non-integer numbers",
                     false, false),
                 //(() => Benchmarker.BenchmarkParsingAndLintingJsonWithErrors(30), "JsonParser performance and performance of JsonLint.message"),
                 (() => Benchmarker.BenchmarkJNodeToString(64, bigRandomFname),