From 2fccb87dcfc575b7618e66c52f8304edae2754c7 Mon Sep 17 00:00:00 2001
From: HHans09 <91560812+HHans09@users.noreply.github.com>
Date: Tue, 17 Jan 2023 16:58:55 -0500
Subject: [PATCH] Fb 1876 : Implement Replicate() func (#2410)

* fb-1876 : creating Replicate fun

* fb-1876: creating string replicate func

* Fb-1876: String Replicate func

* Fb-1876: String Replicate func
---
 sql3/planner/expression.go              |  2 +
 sql3/planner/expressionanalyzercall.go  |  6 ++-
 sql3/planner/inbuiltfunctionsstring.go  | 34 +++++++++++++++-
 sql3/test/defs/defs_string_functions.go | 54 +++++++++++++++++++++++++
 4 files changed, 93 insertions(+), 3 deletions(-)

diff --git a/sql3/planner/expression.go b/sql3/planner/expression.go
index 5fb64ec6f..d76a04807 100644
--- a/sql3/planner/expression.go
+++ b/sql3/planner/expression.go
@@ -1518,6 +1518,8 @@ func (n *callPlanExpression) Evaluate(currentRow []interface{}) (interface{}, er
 		return n.EvaluateSpace(currentRow)
 	case "LEN":
 		return n.EvaluateLen(currentRow)
+	case "REPLICATE":
+		return n.EvaluateReplicate(currentRow)
 	default:
 		return nil, sql3.NewErrInternalf("unhandled function name '%s'", n.name)
 	}
diff --git a/sql3/planner/expressionanalyzercall.go b/sql3/planner/expressionanalyzercall.go
index b7369f361..dc3cfec7f 100644
--- a/sql3/planner/expressionanalyzercall.go
+++ b/sql3/planner/expressionanalyzercall.go
@@ -264,13 +264,15 @@ func (p *ExecutionPlanner) analyzeCallExpression(call *parser.Call, scope parser
 	case "LTRIM":
 		return p.analyseFunctionTrim(call, scope)
 	case "SUFFIX":
-		return p.analyseFunctionPrefixSuffix(call, scope)
+		return p.analyseFunctionPrefixSuffixReplicate(call, scope)
 	case "PREFIX":
-		return p.analyseFunctionPrefixSuffix(call, scope)
+		return p.analyseFunctionPrefixSuffixReplicate(call, scope)
 	case "SPACE":
 		return p.analyseFunctionSpace(call, scope)
 	case "LEN":
 		return p.analyseFunctionLen(call, scope)
+	case "REPLICATE":
+		return p.analyseFunctionPrefixSuffixReplicate(call, scope)
 	default:
 		return nil, sql3.NewErrCallUnknownFunction(call.Name.NamePos.Line, call.Name.NamePos.Column, call.Name.Name)
 	}
diff --git a/sql3/planner/inbuiltfunctionsstring.go b/sql3/planner/inbuiltfunctionsstring.go
index dca5cda21..ad665623c 100644
--- a/sql3/planner/inbuiltfunctionsstring.go
+++ b/sql3/planner/inbuiltfunctionsstring.go
@@ -163,7 +163,7 @@ func (p *ExecutionPlanner) analyseFunctionTrim(call *parser.Call, scope parser.S
 	return call, nil
 }
 
-func (p *ExecutionPlanner) analyseFunctionPrefixSuffix(call *parser.Call, scope parser.Statement) (parser.Expr, error) {
+func (p *ExecutionPlanner) analyseFunctionPrefixSuffixReplicate(call *parser.Call, scope parser.Statement) (parser.Expr, error) {
 	if len(call.Args) != 2 {
 		return nil, sql3.NewErrCallParameterCountMismatch(call.Rparen.Line, call.Rparen.Column, call.Name.Name, 2, len(call.Args))
 	}
@@ -612,3 +612,35 @@ func (n *callPlanExpression) EvaluateLen(currentRow []interface{}) (interface{},
 
 	return int64(len([]rune(stringArg))), nil
 }
+func (n *callPlanExpression) EvaluateReplicate(currentRow []interface{}) (interface{}, error) {
+	argEval, err := n.args[0].Evaluate(currentRow)
+	if err != nil {
+		return nil, err
+	}
+	if argEval == nil {
+		return nil, nil
+	}
+	stringArg, ok := argEval.(string)
+	if !ok {
+		return nil, sql3.NewErrInternalf("unexpected type converion %T", argEval)
+	}
+
+	argEval, err = n.args[1].Evaluate(currentRow)
+	if err != nil {
+		return nil, err
+	}
+	if argEval == nil {
+		return nil, nil
+	}
+	intArg, ok := argEval.(int64)
+	if !ok {
+		return nil, sql3.NewErrInternalf("unexpected type converion %T", argEval)
+	}
+
+	if intArg < 0 {
+		return nil, sql3.NewErrValueOutOfRange(0, 0, intArg)
+	}
+
+	return strings.Repeat(stringArg, int(intArg)), nil
+
+}
diff --git a/sql3/test/defs/defs_string_functions.go b/sql3/test/defs/defs_string_functions.go
index 54529285f..916844b9a 100644
--- a/sql3/test/defs/defs_string_functions.go
+++ b/sql3/test/defs/defs_string_functions.go
@@ -766,5 +766,59 @@ var stringScalarFunctionsTests = TableTest{
 			),
 			Compare: CompareExactOrdered,
 		},
+		{
+			name: "ReplicateString",
+			SQLs: sqls(
+				"select replicate('this',2)",
+			),
+			ExpHdrs: hdrs(
+				hdr("", fldTypeString),
+			),
+			ExpRows: rows(
+				row(string("thisthis")),
+			),
+			Compare: CompareExactOrdered,
+		},
+		{
+			name: "ReplicateNull",
+			SQLs: sqls(
+				"select replicate(null,null)",
+			),
+			ExpHdrs: hdrs(
+				hdr("", fldTypeString),
+			),
+			ExpRows: rows(
+				row(nil),
+			),
+			Compare: CompareExactOrdered,
+		},
+		{
+			name: "ReplicateincorrectArguments",
+			SQLs: sqls(
+				"select replicate('this',)",
+			),
+			ExpErr: "[1:25] 'replicate': count of formal parameters (2) does not match count of actual parameters (1)",
+		},
+		{
+			name: "ReplicateincorrectTypeofArguments",
+			SQLs: sqls(
+				"select replicate(1,2)",
+			),
+			ExpErr: "[1:18] string expression expected",
+		},
+		{
+			name: "ReplicateincorrectTypeofArguments",
+			SQLs: sqls(
+				"select replicate('this','this')",
+			),
+			ExpErr: "[1:25] integer expression expected",
+		},
+		{
+			name: "ReplicateOutofRange",
+			SQLs: sqls(
+				"select replicate('this',-1)",
+			),
+			ExpErr: "[0:0] value '-1' out of range",
+		},
 	},
 }