init - add project files

tools/jet-2.12.0/internal/jet/alias.go

@@ -0,0 +1,32 @@
+package jet
+
+type alias struct {
+	expression Expression
+	alias      string
+}
+
+func newAlias(expression Expression, aliasName string) Projection {
+	return &alias{
+		expression: expression,
+		alias:      aliasName,
+	}
+}
+
+func (a *alias) fromImpl(subQuery SelectTable) Projection {
+	// if alias is in the form "table.column", we break it into two parts so that ProjectionList.As(newAlias) can
+	// overwrite tableName with a new alias. This method is called only for exporting aliased custom columns.
+	// Generated columns have default aliasing.
+	tableName, columnName := extractTableAndColumnName(a.alias)
+
+	column := NewColumnImpl(columnName, tableName, nil)
+	column.subQuery = subQuery
+
+	return &column
+}
+
+func (a *alias) serializeForProjection(statement StatementType, out *SQLBuilder) {
+	a.expression.serialize(statement, out)
+
+	out.WriteString("AS")
+	out.WriteAlias(a.alias)
+}