unescapePathName on the columnName parsed from partition path.

Author: juliuszsompolski

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/PartitioningUtils.scala

@@ -243,7 +243,7 @@ object PartitioningUtils {
     if (equalSignIndex == -1) {
       None
     } else {
-      val columnName = columnSpec.take(equalSignIndex)
+      val columnName = unescapePathName(columnSpec.take(equalSignIndex))
       assert(columnName.nonEmpty, s"Empty partition column name in '$columnSpec'")
 
       val rawColumnValue = columnSpec.drop(equalSignIndex + 1)

sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/FileIndexSuite.scala

@@ -27,6 +27,7 @@ import org.apache.hadoop.fs.{FileStatus, Path, RawLocalFileSystem}
 
 import org.apache.spark.metrics.source.HiveCatalogMetrics
 import org.apache.spark.sql.catalyst.util._
+import org.apache.spark.sql.functions.col
 import org.apache.spark.sql.internal.SQLConf
 import org.apache.spark.sql.test.SharedSQLContext
 import org.apache.spark.util.{KnownSizeEstimation, SizeEstimator}
@@ -236,6 +237,17 @@ class FileIndexSuite extends SharedSQLContext {
     val fileStatusCache = FileStatusCache.getOrCreate(spark)
     fileStatusCache.putLeafFiles(new Path("/tmp", "abc"), files.toArray)
   }
+
+  test("SPARK-20367 - properly unescape column names in inferPartitioning") {
+    withTempPath { path =>
+      val colToUnescape = "Column/#%'?"
+      spark
+        .range(1)
+        .select(col("id").as(colToUnescape), col("id"))
+        .write.partitionBy(colToUnescape).parquet(path.getAbsolutePath)
+      assert(spark.read.parquet(path.getAbsolutePath).schema.exists(_.name == colToUnescape))
+    }
+  }
 }
 
 class FakeParentPathFileSystem extends RawLocalFileSystem {