Github user kevinyu98 commented on a diff in the pull request:

    https://github.com/apache/spark/pull/12646#discussion_r114703725
  
    --- Diff: 
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringExpressions.scala
 ---
    @@ -461,68 +462,270 @@ case class FindInSet(left: Expression, right: 
Expression) extends BinaryExpressi
     }
     
     /**
    - * A function that trim the spaces from both ends for the specified string.
    + * A function that trim the spaces or a character from both ends for the 
specified string.
      */
     @ExpressionDescription(
    -  usage = "_FUNC_(str) - Removes the leading and trailing space characters 
from `str`.",
    +  usage = """
    +    _FUNC_(str) - Removes the leading and trailing space characters from 
`str`.
    +    _FUNC_(BOTH trimChar FROM str) - Remove the leading and trailing 
trimChar from `str`
    +    _FUNC_(LEADING trimChar FROM str) - Remove the leading trimChar from 
`str`
    +    _FUNC_(TRAILING trimChar FROM str) - Remove the trailing trimChar from 
`str`
    +  """,
       extended = """
    +    Arguments:
    +      str - a string expression
    +      trimChar - the trim character
    +      BOTH, FROM - these are keyword to specify for trim character from 
both side of the string
    +      LEADING, FROM - these are keyword to specify for trim character from 
left side of the string
    +      TRAILING, FROM - these are keyword to specify for trim character 
from right side of the string
         Examples:
           > SELECT _FUNC_('    SparkSQL   ');
            SparkSQL
    +      > SELECT _FUNC_(BOTH 'S' FROM 'SSparkSQLS');
    +       parkSQL
    +      > SELECT _FUNC_(LEADING 'S' FROM 'SSparkSQLS');
    +       parkSQLS
    +      > SELECT _FUNC_(TRAILING 'S' FROM 'SSparkSQLS');
    +       SSparkSQL
       """)
    -case class StringTrim(child: Expression)
    -  extends UnaryExpression with String2StringExpression {
    +case class StringTrim(children: Seq[Expression])
    +  extends Expression with ImplicitCastInputTypes {
     
    -  def convert(v: UTF8String): UTF8String = v.trim()
    +  require(children.size <= 2 && children.nonEmpty,
    +    s"$prettyName requires at least one argument and no more than two.")
    +
    +  override def dataType: DataType = StringType
    +  override def inputTypes: Seq[AbstractDataType] = 
Seq.fill(children.size)(StringType)
    +
    +  override def nullable: Boolean = children.exists(_.nullable)
    +  override def foldable: Boolean = children.forall(_.foldable)
     
       override def prettyName: String = "trim"
     
    +  override def eval(input: InternalRow): Any = {
    +    val inputs = children.map(_.eval(input).asInstanceOf[UTF8String])
    +    if (inputs(0) != null) {
    +      if (children.size == 1) {
    +        return inputs(0).trim()
    +      } else if (inputs(1) != null) {
    +        if (inputs(0).numChars > 1) {
    +          throw new AnalysisException(s"Trim character '${inputs(0)}' can 
not be greater than " +
    +            s"1 character.")
    +        } else {
    +          return inputs(1).trim(inputs(0))
    +        }
    +      }
    +    }
    +    null
    +  }
    +
       override def doGenCode(ctx: CodegenContext, ev: ExprCode): ExprCode = {
    -    defineCodeGen(ctx, ev, c => s"($c).trim()")
    +    if (children.size == 2 &&
    +      (! children(0).isInstanceOf[Literal] || children(0).toString.length 
> 1)) {
    +      throw new AnalysisException(s"The trimming parameter should be 
Literal " +
    +        s"and only one character.") }
    +
    +    val evals = children.map(_.genCode(ctx))
    +    val inputs = evals.map { eval =>
    +      s"${eval.isNull} ? null : ${eval.value}"
    +    }
    +    val getTrimFunction = if (children.size == 1) {
    +      s"""UTF8String ${ev.value} = ${inputs(0)}.trim();"""
    +    } else {
    +      s"""UTF8String ${ev.value} = 
${inputs(1)}.trim(${inputs(0)});""".stripMargin
    +    }
    +    ev.copy(evals.map(_.code).mkString("\n") +
    +      s"""
    +    boolean ${ev.isNull} = false;
    +    ${getTrimFunction};
    +    if (${ev.value} == null) {
    +      ${ev.isNull} = true;
    +    }
    +    """)
    +    }
    +
    +  override def sql: String = {
    +    if (children.size == 1) {
    +      val childrenSQL = children.map(_.sql).mkString(", ")
    +      s"$prettyName($childrenSQL)"
    +    } else {
    +      val trimSQL = children(0).map(_.sql).mkString(", ")
    +      val tarSQL = children(1).map(_.sql).mkString(", ")
    +      s"$prettyName($trimSQL, $tarSQL)"
    +    }
       }
     }
     
     /**
    - * A function that trim the spaces from left end for given string.
    + * A function that trim the spaces or a character from left end for given 
string.
      */
     @ExpressionDescription(
    -  usage = "_FUNC_(str) - Removes the leading and trailing space characters 
from `str`.",
    +  usage = """
    +    _FUNC_(str) - Removes the leading space characters from `str`.
    +    _FUNC_(trimChar, str) - Remove the leading trimChar from `str`
    --- End diff --
    
    ok, I will make changes. Thanks


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

Reply via email to