Parse nullable int column values.

lib/token/colmetadata-token-parser.coffee

@@ -1,6 +1,7 @@
 # s2.2.7.4
 
 TYPE = require('./data-type').TYPE
+sprintf = require('sprintf').sprintf
 
 parser = (buffer, position) ->
   startPosition = position
@@ -27,6 +28,7 @@ parser = (buffer, position) ->
 
     if !type
       error = "Unrecognised data type #{typeNumber} at offset #{position - 1}"
+      error = sprintf('Unrecognised data type 0x%02X at offset 0x%04X', typeNumber, (position - 1))
       break
 
     #console.log(type)

lib/token/data-type.coffee

@@ -62,6 +62,11 @@ TYPE =
     dataLength: 8
 
   # Variable-length types
+  0x26:
+    type: 'INTNTYPE'
+    name: 'IntN'
+    variableLength: true
+    dataLengthLength: 1
   0xA7:
     type: 'BIGVARCHR'
     name: 'VarChar'

lib/token/row-token-parser.coffee

@@ -10,6 +10,8 @@ parser = (buffer, position, columnsMetaData) ->
 
   columns = []
   for columnMetaData in columnsMetaData
+    #console.log sprintf('Token @ 0x%02X', position)
+
     isNull = false
     type = columnMetaData.type
     switch type.name
@@ -18,6 +20,27 @@ parser = (buffer, position, columnsMetaData) ->
           return false
         value = buffer.readUInt32LE(position)
         position += type.dataLength
+      when 'IntN'
+        if buffer.length - position < 1
+          return false
+        dataLength = buffer.readUInt8(position)
+        position++
+
+        if buffer.length - position < dataLength
+          return false
+
+        #console.log dataLength, position
+        switch dataLength
+          when 0
+            isNull = true
+          when 1
+            value = buffer.readUInt8(position)
+          when 2
+            value = buffer.readUInt16LE(position)
+          when 4
+            value = buffer.readUInt32LE(position)
+
+        position += dataLength
       when 'VarChar', 'Char'
         if buffer.length - position < 2
           return false
@@ -52,6 +75,7 @@ parser = (buffer, position, columnsMetaData) ->
 
     columns.push(
       value: value
+      isNull: isNull,
       metadata: columnMetaData
     )
 

test/integration/connection-test.coffee

@@ -25,7 +25,7 @@ exports.connect = (test) ->
   )
 
 exports.execSimpleSql = (test) ->
-  test.expect(12)
+  test.expect(15)
 
   connection = new Connection(config.server, config.userName, config.password, config.options, (err, loggedIn) ->
     test.ok(!err)
@@ -48,6 +48,10 @@ exports.execSimpleSql = (test) ->
     test.strictEqual(columns[0].value, 8)
     test.strictEqual(columns[1].value, 'abc')
     test.strictEqual(columns[2].value, 'def')
+
+    test.strictEqual(columns[0].isNull, false)
+    test.strictEqual(columns[1].isNull, false)
+    test.strictEqual(columns[2].isNull, false)
 
     byName = columns.byName()
     test.strictEqual(byName.C1.value, 8)
@@ -59,6 +63,38 @@ exports.execSimpleSql = (test) ->
     #console.log(message)
   )
 
+exports.execSqlReturningNulls = (test) ->
+  test.expect(11)
+
+  connection = new Connection(config.server, config.userName, config.password, config.options, (err, loggedIn) ->
+    test.ok(!err)
+    test.ok(loggedIn)
+
+    connection.execSql("select cast(null as int), cast(1 as int), cast(null as varchar(1)), cast(null as nvarchar(1))", (err, rowCount) ->
+      test.ok(!err)
+      test.strictEqual(rowCount, 1)
+      test.done()
+    )
+  )
+
+  connection.on('columnMetadata', (columnsMetadata) ->
+    test.strictEqual(columnsMetadata.length, 4)
+  )
+
+  connection.on('row', (columns) ->
+    test.strictEqual(columns.length, 4)
+
+    test.strictEqual(columns[0].isNull, true)
+    test.strictEqual(columns[1].isNull, false)
+    test.strictEqual(columns[1].value, 1)
+    test.strictEqual(columns[2].isNull, true)
+    test.strictEqual(columns[3].isNull, true)
+  )
+
+  connection.on('debug', (message) ->
+    #console.log(message)
+  )
+
 exports.execSqlWithLotsOfRowsReturned = (test) ->
   numberOfRows = 1000
   rowsReceived = 0