fixes

Author: jennifersp

sql/databases.go

@@ -57,7 +57,8 @@ type CollatedDatabaseProvider interface {
 // TableFunctionProvider is an interface that allows custom table functions to be provided. It's usually (but not
 // always) implemented by a DatabaseProvider.
 type TableFunctionProvider interface {
-	// TableFunction returns the table function with the name provided, case-insensitive
+	// TableFunction returns the table function with the name provided, case-insensitive.
+	// It also returns boolean param for whether the table function was found.
 	TableFunction(ctx *Context, name string) (TableFunction, bool)
 	// WithTableFunctions returns a new provider with (only) the list of table functions arguments
 	WithTableFunctions(fns ...TableFunction) (TableFunctionProvider, error)

sql/expression/tablefunction/table_function.go

@@ -21,24 +21,28 @@ import (
 	"github.com/dolthub/go-mysql-server/sql"
 )
 
-var _ sql.TableFunction = &TableFunction{}
-var _ sql.ExecSourceRel = &TableFunction{}
+var _ sql.TableFunction = &TableFunctionWrapper{}
+var _ sql.ExecSourceRel = &TableFunctionWrapper{}
 
-type TableFunction struct {
+// TableFunctionWrapper represents a table function with underlying
+// regular function. It allows using regular function as table function.
+type TableFunctionWrapper struct {
 	underlyingFunc sql.Function
 
 	args     []sql.Expression
 	database sql.Database
 	funcExpr sql.Expression
 }
 
-func NewTableFunction(f sql.Function) sql.TableFunction {
-	return &TableFunction{
+// NewTableFunctionWrapper creates new TableFunction
+// with given Function as underlying function.
+func NewTableFunctionWrapper(f sql.Function) sql.TableFunction {
+	return &TableFunctionWrapper{
 		underlyingFunc: f,
 	}
 }
 
-func (t *TableFunction) NewInstance(ctx *sql.Context, db sql.Database, args []sql.Expression) (sql.Node, error) {
+func (t *TableFunctionWrapper) NewInstance(ctx *sql.Context, db sql.Database, args []sql.Expression) (sql.Node, error) {
 	nt := *t
 	nt.database = db
 	nt.args = args
@@ -50,67 +54,77 @@ func (t *TableFunction) NewInstance(ctx *sql.Context, db sql.Database, args []sq
 	return &nt, nil
 }
 
-func (t *TableFunction) Children() []sql.Node {
+func (t *TableFunctionWrapper) Children() []sql.Node {
 	return nil
 }
 
-func (t *TableFunction) Database() sql.Database {
+func (t *TableFunctionWrapper) Database() sql.Database {
 	return t.database
 }
 
-func (t *TableFunction) Expressions() []sql.Expression {
+func (t *TableFunctionWrapper) Expressions() []sql.Expression {
+	if t.funcExpr == nil {
+		return nil
+	}
 	return t.funcExpr.Children()
 }
 
-func (t *TableFunction) IsReadOnly() bool {
+func (t *TableFunctionWrapper) IsReadOnly() bool {
 	return true
 }
 
-func (t *TableFunction) Name() string {
+func (t *TableFunctionWrapper) Name() string {
 	return t.underlyingFunc.FunctionName()
 }
 
-func (t *TableFunction) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
+func (t *TableFunctionWrapper) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
 	v, err := t.funcExpr.Eval(ctx, r)
 	if err != nil {
 		return nil, err
 	}
 	return sql.RowsToRowIter(sql.Row{v}), nil
 }
 
-func (t *TableFunction) Resolved() bool {
+func (t *TableFunctionWrapper) Resolved() bool {
 	for _, expr := range t.args {
-		return expr.Resolved()
+		if !expr.Resolved() {
+			return false
+		}
 	}
 	return true
 }
 
-func (t *TableFunction) Schema() sql.Schema {
+func (t *TableFunctionWrapper) Schema() sql.Schema {
 	return sql.Schema{&sql.Column{Name: t.underlyingFunc.FunctionName(), Type: t.funcExpr.Type()}}
 }
 
-func (t *TableFunction) String() string {
+func (t *TableFunctionWrapper) String() string {
 	var args []string
 	for _, expr := range t.args {
 		args = append(args, expr.String())
 	}
 	return fmt.Sprintf("%s(%s)", t.underlyingFunc.FunctionName(), strings.Join(args, ", "))
 }
 
-func (t *TableFunction) WithChildren(children ...sql.Node) (sql.Node, error) {
+func (t *TableFunctionWrapper) WithChildren(children ...sql.Node) (sql.Node, error) {
 	if len(children) != 0 {
-		return nil, fmt.Errorf("unexpected children")
+		return nil, sql.ErrInvalidChildrenNumber.New(t, len(children), 0)
 	}
 	return t, nil
 }
 
-func (t *TableFunction) WithDatabase(database sql.Database) (sql.Node, error) {
+func (t *TableFunctionWrapper) WithDatabase(database sql.Database) (sql.Node, error) {
 	nt := *t
 	nt.database = database
 	return &nt, nil
 }
 
-func (t *TableFunction) WithExpressions(exprs ...sql.Expression) (sql.Node, error) {
+func (t *TableFunctionWrapper) WithExpressions(exprs ...sql.Expression) (sql.Node, error) {
+	if t.funcExpr == nil {
+		if len(exprs) != 0 {
+			return nil, sql.ErrInvalidChildrenNumber.New(t, len(exprs), 0)
+		}
+	}
 	l := len(t.funcExpr.Children())
 	if len(exprs) != l {
 		return nil, sql.ErrInvalidChildrenNumber.New(t, len(exprs), l)

sql/planbuilder/from.go

@@ -467,7 +467,7 @@ func (b *Builder) buildTableFunc(inScope *scope, t *ast.TableFuncExpr) (outScope
 		if !funcFound {
 			b.handleErr(sql.ErrTableFunctionNotFound.New(utf.Name()))
 		}
-		tableFunction = dtablefunctions.NewTableFunction(f)
+		tableFunction = dtablefunctions.NewTableFunctionWrapper(f)
 	}
 
 	database := b.currentDb()