Merge pull request #363 from erizocosmico/fix/squash-filter

internal/rule: fix indexes of filters in squash

Author: ajnavarro

integration_test.go

@@ -17,6 +17,7 @@ import (
 	"gopkg.in/src-d/go-mysql-server.v0/sql"
 	"gopkg.in/src-d/go-mysql-server.v0/sql/analyzer"
 	"gopkg.in/src-d/go-mysql-server.v0/sql/expression"
+	sqlfunction "gopkg.in/src-d/go-mysql-server.v0/sql/expression/function"
 	"gopkg.in/src-d/go-mysql-server.v0/sql/index/pilosa"
 )
 
@@ -160,6 +161,26 @@ func TestIntegration(t *testing.T) {
 				{"6ecf0ef2c2dffb796033e5a02219af86ec6584e5", int32(9)},
 			},
 		},
+		{
+			`SELECT MONTH(committer_when) as month,
+				r.repository_id as repo_id,
+				committer_email
+			FROM ref_commits r
+			INNER JOIN commits c
+				ON YEAR(c.committer_when) = 2015
+				AND r.commit_hash = c.commit_hash
+			WHERE r.ref_name = 'HEAD'`,
+			[]sql.Row{
+				{int32(4), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+				{int32(3), "worktree", "[email protected]"},
+			},
+		},
 	}
 
 	runTests := func(t *testing.T) {
@@ -776,6 +797,7 @@ func newSquashEngine() *sqle.Engine {
 		Build()
 	e := sqle.New(catalog, analyzer)
 	e.AddDatabase(gitbase.NewDatabase("foo"))
+	e.Catalog.RegisterFunctions(sqlfunction.Defaults)
 	e.Catalog.RegisterFunctions(function.Functions)
 	return e
 }

internal/rule/squashjoins.go

@@ -61,27 +61,34 @@ func SquashJoins(
 	}
 
 	return n.TransformUp(func(n sql.Node) (sql.Node, error) {
-		if projectSquashes <= 0 {
-			return n, nil
-		}
+		switch n := n.(type) {
+		case *plan.Project:
+			if projectSquashes <= 0 {
+				return n, nil
+			}
 
-		project, ok := n.(*plan.Project)
-		if !ok {
-			return n, nil
-		}
+			child, ok := n.Child.(*plan.Project)
+			if !ok {
+				return n, nil
+			}
 
-		child, ok := project.Child.(*plan.Project)
-		if !ok {
-			return n, nil
-		}
+			squashedProject, ok := squashProjects(n, child)
+			if !ok {
+				return n, nil
+			}
 
-		squashedProject, ok := squashProjects(project, child)
-		if !ok {
+			projectSquashes--
+			return squashedProject, nil
+		case *plan.Filter:
+			expr, err := fixFieldIndexes(n.Expression, n.Schema())
+			if err != nil {
+				return nil, err
+			}
+
+			return plan.NewFilter(expr, n.Child), nil
+		default:
 			return n, nil
 		}
-
-		projectSquashes--
-		return squashedProject, nil
 	})
 }
 
@@ -101,7 +108,7 @@ func countProjectSquashes(n sql.Node) int {
 }
 
 func squashProjects(parent, child *plan.Project) (sql.Node, bool) {
-	projections := []sql.Expression{}
+	var projections []sql.Expression
 	for _, expr := range parent.Expressions() {
 		parentField, ok := expr.(*expression.GetField)
 		if !ok {
@@ -1078,7 +1085,7 @@ func (t *squashedTable) TransformExpressionsUp(sql.TransformExprFunc) (sql.Node,
 	return t, nil
 }
 func (t *squashedTable) TransformUp(fn sql.TransformNodeFunc) (sql.Node, error) {
-	return t, nil
+	return fn(t)
 }
 
 type schemaMapperIter struct {

internal/rule/squashjoins_test.go

@@ -96,6 +96,16 @@ func TestSquashJoins(t *testing.T) {
 
 	result, err := SquashJoins(sql.NewEmptyContext(), analyzer.NewDefault(nil), node)
 	require.NoError(err)
+	result, err = result.TransformUp(func(n sql.Node) (sql.Node, error) {
+		t, ok := n.(*squashedTable)
+		if ok {
+			t.schema = nil
+			return t, nil
+		}
+
+		return n, nil
+	})
+	require.NoError(err)
 	require.Equal(expected, result)
 }