From b6dfe730512c81425d52442d67960c4cbd53fcf8 Mon Sep 17 00:00:00 2001
From: Ankush Rayabhari <ankush.rayabhari@gmail.com>
Date: Mon, 31 Aug 2020 18:21:32 -0700
Subject: [PATCH] Fix segfault on printing cast/extract exprs

- Additionally, fix printing logic
---
 src/sql/Expr.cpp       |  4 ++--
 src/sql/Expr.h         |  3 ++-
 src/util/sqlhelper.cpp | 36 ++++++++++++++++++++++++++++++++++++
 3 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/sql/Expr.cpp b/src/sql/Expr.cpp
index c2103a3..6804fc5 100644
--- a/src/sql/Expr.cpp
+++ b/src/sql/Expr.cpp
@@ -218,7 +218,7 @@ Expr* Expr::makeInOperator(Expr* expr, SelectStatement* select) {
 }
 
 Expr* Expr::makeExtract(DatetimeField datetimeField, Expr* expr) {
-    Expr* e = new Expr(kExprFunctionRef);
+    Expr* e = new Expr(kExprExtract);
     e->name = strdup("EXTRACT");
     e->datetimeField = datetimeField;
     e->expr = expr;
@@ -226,7 +226,7 @@ Expr* Expr::makeExtract(DatetimeField datetimeField, Expr* expr) {
 }
 
 Expr* Expr::makeCast(Expr* expr, ColumnType columnType) {
-    Expr* e = new Expr(kExprFunctionRef);
+    Expr* e = new Expr(kExprCast);
     e->name = strdup("CAST");
     e->columnType = columnType;
     e->expr = expr;
diff --git a/src/sql/Expr.h b/src/sql/Expr.h
index 6939e3f..cb5bddb 100644
--- a/src/sql/Expr.h
+++ b/src/sql/Expr.h
@@ -27,7 +27,8 @@ enum ExprType {
     kExprHint,
     kExprArray,
     kExprArrayIndex,
-    kExprDatetimeField
+    kExprExtract,
+    kExprCast    
 };
 
 // Operator types. These are important for expressions of type kExprOperator.
diff --git a/src/util/sqlhelper.cpp b/src/util/sqlhelper.cpp
index 74a5b4d..e31ff78 100755
--- a/src/util/sqlhelper.cpp
+++ b/src/util/sqlhelper.cpp
@@ -10,6 +10,7 @@ namespace hsql {
   void printAlias(Alias* alias, uintmax_t numIndent);
 
   std::ostream& operator<<(std::ostream& os, const OperatorType& op);
+  std::ostream& operator<<(std::ostream& os, const DatetimeField& op);
 
   std::string indent(uintmax_t numIndent) {
     return std::string(numIndent, '\t');
@@ -32,6 +33,12 @@ namespace hsql {
   void inprint(const OperatorType& op, uintmax_t numIndent) {
     std::cout << indent(numIndent) << op << std::endl;
   }
+  void inprint(const ColumnType& colType, uintmax_t numIndent) {
+    std::cout << indent(numIndent) << colType << std::endl;
+  }
+  void inprint(const DatetimeField& colType, uintmax_t numIndent) {
+    std::cout << indent(numIndent) << colType << std::endl;
+  }
 
   void printTableRefInfo(TableRef* table, uintmax_t numIndent) {
     switch (table->type) {
@@ -118,6 +125,16 @@ namespace hsql {
       inprint(expr->name, numIndent);
       for (Expr* e : *expr->exprList) printExpression(e, numIndent + 1);
       break;
+    case kExprExtract:
+      inprint(expr->name, numIndent);
+      inprint(expr->datetimeField, numIndent + 1);
+      printExpression(expr->expr, numIndent + 1);
+      break;
+    case kExprCast:
+      inprint(expr->name, numIndent);
+      inprint(expr->columnType, numIndent + 1);
+      printExpression(expr->expr, numIndent + 1);
+      break;
     case kExprOperator:
       printOperatorExpression(expr, numIndent);
       break;
@@ -372,4 +389,23 @@ namespace hsql {
     }
   }
 
+  std::ostream& operator<<(std::ostream& os, const DatetimeField& datetime) {
+    static const std::map<const DatetimeField, const std::string> operatorToToken = {
+      {kDatetimeNone, "None"},
+      {kDatetimeSecond, "SECOND"},
+      {kDatetimeMinute, "MINUTE"},
+      {kDatetimeHour, "HOUR"},
+      {kDatetimeDay, "DAY"},
+      {kDatetimeMonth, "MONTH"},
+      {kDatetimeYear, "YEAR"}
+    };
+
+    const auto found = operatorToToken.find(datetime);
+    if (found == operatorToToken.cend()) {
+      return os << static_cast<uint64_t>(datetime);
+    } else {
+      return os << (*found).second;
+    }
+  }
+
 } // namespace hsql