Extracted out evaluators

cmd/evaluate_all_command.go

@@ -40,23 +40,23 @@ func evaluateAll(cmd *cobra.Command, args []string) error {
 		colorsEnabled = true
 	}
 	printer := yqlib.NewPrinter(out, outputToJSON, unwrapScalar, colorsEnabled, indent, !noDocSeparators)
-
+	allAtOnceEvaluator := yqlib.NewAllAtOnceEvaluator()
 	switch len(args) {
 	case 0:
 		if pipingStdIn {
-			err = yqlib.EvaluateAllFileStreams("", []string{"-"}, printer)
+			err = allAtOnceEvaluator.EvaluateFiles("", []string{"-"}, printer)
 		} else {
 			cmd.Println(cmd.UsageString())
 			return nil
 		}
 	case 1:
 		if nullInput {
-			err = yqlib.EvaluateAllFileStreams(args[0], []string{}, printer)
+			err = allAtOnceEvaluator.EvaluateFiles(args[0], []string{}, printer)
 		} else {
-			err = yqlib.EvaluateAllFileStreams("", []string{args[0]}, printer)
+			err = allAtOnceEvaluator.EvaluateFiles("", []string{args[0]}, printer)
 		}
 	default:
-		err = yqlib.EvaluateAllFileStreams(args[0], args[1:], printer)
+		err = allAtOnceEvaluator.EvaluateFiles(args[0], args[1:], printer)
 	}
 
 	cmd.SilenceUsage = true

cmd/evalute_sequence_command.go

@@ -41,22 +41,25 @@ func evaluateSequence(cmd *cobra.Command, args []string) error {
 	}
 	printer := yqlib.NewPrinter(out, outputToJSON, unwrapScalar, colorsEnabled, indent, !noDocSeparators)
 
+	streamEvaluator := yqlib.NewStreamEvaluator()
+	allAtOnceEvaluator := yqlib.NewAllAtOnceEvaluator()
+
 	switch len(args) {
 	case 0:
 		if pipingStdIn {
-			err = yqlib.EvaluateFileStreamsSequence("", []string{"-"}, printer)
+			err = streamEvaluator.EvaluateFiles("", []string{"-"}, printer)
 		} else {
 			cmd.Println(cmd.UsageString())
 			return nil
 		}
 	case 1:
 		if nullInput {
-			err = yqlib.EvaluateAllFileStreams(args[0], []string{}, printer)
+			err = allAtOnceEvaluator.EvaluateFiles(args[0], []string{}, printer)
 		} else {
-			err = yqlib.EvaluateFileStreamsSequence("", []string{args[0]}, printer)
+			err = streamEvaluator.EvaluateFiles("", []string{args[0]}, printer)
 		}
 	default:
-		err = yqlib.EvaluateFileStreamsSequence(args[0], args[1:], printer)
+		err = streamEvaluator.EvaluateFiles(args[0], args[1:], printer)
 	}
 
 	cmd.SilenceUsage = true

pkg/yqlib/all_at_once_evaluator.go

@@ -0,0 +1,45 @@
+package yqlib
+
+import "container/list"
+
+/**
+	Loads all yaml documents of all files given into memory, then runs the given expression once.
+**/
+type Evaluator interface {
+	EvaluateFiles(expression string, filenames []string, printer Printer) error
+}
+
+type allAtOnceEvaluator struct {
+	treeNavigator DataTreeNavigator
+	treeCreator   PathTreeCreator
+}
+
+func NewAllAtOnceEvaluator() Evaluator {
+	return &allAtOnceEvaluator{treeNavigator: NewDataTreeNavigator(), treeCreator: NewPathTreeCreator()}
+}
+
+func (e *allAtOnceEvaluator) EvaluateFiles(expression string, filenames []string, printer Printer) error {
+	fileIndex := 0
+	node, err := treeCreator.ParsePath(expression)
+	if err != nil {
+		return err
+	}
+	var allDocuments *list.List = list.New()
+	for _, filename := range filenames {
+		reader, err := readStream(filename)
+		if err != nil {
+			return err
+		}
+		fileDocuments, err := readDocuments(reader, filename, fileIndex)
+		if err != nil {
+			return err
+		}
+		allDocuments.PushBackList(fileDocuments)
+		fileIndex = fileIndex + 1
+	}
+	matches, err := treeNavigator.GetMatchingNodes(allDocuments, node)
+	if err != nil {
+		return err
+	}
+	return printer.PrintResults(matches)
+}

pkg/yqlib/data_tree_navigator.go

@@ -5,17 +5,9 @@ import (
 
 	"container/list"
 
-	"gopkg.in/op/go-logging.v1"
+	logging "gopkg.in/op/go-logging.v1"
 )
 
-type dataTreeNavigator struct {
-	navigationPrefs NavigationPrefs
-}
-
-type NavigationPrefs struct {
-	FollowAlias bool
-}
-
 type DataTreeNavigator interface {
 	// given a list of CandidateEntities and a pathNode,
 	// this will process the list against the given pathNode and return
@@ -23,8 +15,11 @@ type DataTreeNavigator interface {
 	GetMatchingNodes(matchingNodes *list.List, pathNode *PathTreeNode) (*list.List, error)
 }
 
-func NewDataTreeNavigator(navigationPrefs NavigationPrefs) DataTreeNavigator {
+type dataTreeNavigator struct {
-	return &dataTreeNavigator{navigationPrefs}
+}
+
+func NewDataTreeNavigator() DataTreeNavigator {
+	return &dataTreeNavigator{}
 }
 
 func (d *dataTreeNavigator) GetMatchingNodes(matchingNodes *list.List, pathNode *PathTreeNode) (*list.List, error) {

pkg/yqlib/doc/File Operators.md

@@ -29,6 +29,6 @@ yq eval 'fileIndex' sample.yml
 ```
 will output
 ```yaml
-73
+0
 ```
 

pkg/yqlib/operators_test.go

@@ -90,7 +90,8 @@ func formatYaml(yaml string) string {
 	if err != nil {
 		panic(err)
 	}
-	err = EvaluateStream("sample.yaml", strings.NewReader(yaml), node, printer)
+	streamEvaluator := NewStreamEvaluator()
+	err = streamEvaluator.Evaluate("sample.yaml", strings.NewReader(yaml), node, printer)
 	if err != nil {
 		panic(err)
 	}
@@ -161,12 +162,14 @@ func documentScenarios(t *testing.T, title string, scenarios []expressionScenari
 				if err != nil {
 					t.Error(err)
 				}
-				err = EvaluateStream("sample.yaml", strings.NewReader(formattedDoc), node, printer)
+				streamEvaluator := NewStreamEvaluator()
+				err = streamEvaluator.Evaluate("sample.yaml", strings.NewReader(formattedDoc), node, printer)
 				if err != nil {
 					t.Error(err)
 				}
 			} else {
-				err = EvaluateAllFileStreams(s.expression, []string{}, printer)
+				allAtOnceEvaluator := NewAllAtOnceEvaluator()
+				err = allAtOnceEvaluator.EvaluateFiles(s.expression, []string{}, printer)
 				if err != nil {
 					t.Error(err)
 				}

pkg/yqlib/stream_evaluator.go

@@ -0,0 +1,85 @@
+package yqlib
+
+import (
+	"container/list"
+	"io"
+	"os"
+
+	yaml "gopkg.in/yaml.v3"
+)
+
+type StreamEvaluator interface {
+	Evaluate(filename string, reader io.Reader, node *PathTreeNode, printer Printer) error
+	EvaluateFiles(expression string, filenames []string, printer Printer) error
+}
+
+type streamEvaluator struct {
+	treeNavigator DataTreeNavigator
+	treeCreator   PathTreeCreator
+	fileIndex     int
+}
+
+func NewStreamEvaluator() StreamEvaluator {
+	return &streamEvaluator{treeNavigator: NewDataTreeNavigator(), treeCreator: NewPathTreeCreator()}
+}
+
+func (s *streamEvaluator) EvaluateFiles(expression string, filenames []string, printer Printer) error {
+
+	node, err := treeCreator.ParsePath(expression)
+	if err != nil {
+		return err
+	}
+
+	for _, filename := range filenames {
+		reader, err := readStream(filename)
+		if err != nil {
+			return err
+		}
+		err = s.Evaluate(filename, reader, node, printer)
+		if err != nil {
+			return err
+		}
+
+		switch reader := reader.(type) {
+		case *os.File:
+			safelyCloseFile(reader)
+		}
+	}
+	return nil
+}
+
+func (s *streamEvaluator) Evaluate(filename string, reader io.Reader, node *PathTreeNode, printer Printer) error {
+
+	var currentIndex uint
+
+	decoder := yaml.NewDecoder(reader)
+	for {
+		var dataBucket yaml.Node
+		errorReading := decoder.Decode(&dataBucket)
+
+		if errorReading == io.EOF {
+			s.fileIndex = s.fileIndex + 1
+			return nil
+		} else if errorReading != nil {
+			return errorReading
+		}
+		candidateNode := &CandidateNode{
+			Document:  currentIndex,
+			Filename:  filename,
+			Node:      &dataBucket,
+			FileIndex: s.fileIndex,
+		}
+		inputList := list.New()
+		inputList.PushBack(candidateNode)
+
+		matches, errorParsing := treeNavigator.GetMatchingNodes(inputList, node)
+		if errorParsing != nil {
+			return errorParsing
+		}
+		err := printer.PrintResults(matches)
+		if err != nil {
+			return err
+		}
+		currentIndex = currentIndex + 1
+	}
+}

pkg/yqlib/utils.go

@@ -11,11 +11,9 @@ import (
 
 //TODO: convert to interface + struct
 
-var treeNavigator = NewDataTreeNavigator(NavigationPrefs{})
+var treeNavigator = NewDataTreeNavigator()
 var treeCreator = NewPathTreeCreator()
 
-var fileIndex = 0
-
 func readStream(filename string) (io.Reader, error) {
 	if filename == "-" {
 		return bufio.NewReader(os.Stdin), nil
@@ -24,42 +22,6 @@ func readStream(filename string) (io.Reader, error) {
 	}
 }
 
-func EvaluateStream(filename string, reader io.Reader, node *PathTreeNode, printer Printer) error {
-
-	var currentIndex uint = 0
-
-	decoder := yaml.NewDecoder(reader)
-	for {
-		var dataBucket yaml.Node
-		errorReading := decoder.Decode(&dataBucket)
-
-		if errorReading == io.EOF {
-			fileIndex = fileIndex + 1
-			return nil
-		} else if errorReading != nil {
-			return errorReading
-		}
-		candidateNode := &CandidateNode{
-			Document:  currentIndex,
-			Filename:  filename,
-			Node:      &dataBucket,
-			FileIndex: fileIndex,
-		}
-		inputList := list.New()
-		inputList.PushBack(candidateNode)
-
-		matches, errorParsing := treeNavigator.GetMatchingNodes(inputList, node)
-		if errorParsing != nil {
-			return errorParsing
-		}
-		err := printer.PrintResults(matches)
-		if err != nil {
-			return err
-		}
-		currentIndex = currentIndex + 1
-	}
-}
-
 func readDocuments(reader io.Reader, filename string, fileIndex int) (*list.List, error) {
 	decoder := yaml.NewDecoder(reader)
 	inputList := list.New()
@@ -91,57 +53,6 @@ func readDocuments(reader io.Reader, filename string, fileIndex int) (*list.List
 	}
 }
 
-func EvaluateAllFileStreams(expression string, filenames []string, printer Printer) error {
-	fileIndex := 0
-	node, err := treeCreator.ParsePath(expression)
-	if err != nil {
-		return err
-	}
-	var allDocuments *list.List = list.New()
-	for _, filename := range filenames {
-		reader, err := readStream(filename)
-		if err != nil {
-			return err
-		}
-		fileDocuments, err := readDocuments(reader, filename, fileIndex)
-		if err != nil {
-			return err
-		}
-		allDocuments.PushBackList(fileDocuments)
-		fileIndex = fileIndex + 1
-	}
-	matches, err := treeNavigator.GetMatchingNodes(allDocuments, node)
-	if err != nil {
-		return err
-	}
-	return printer.PrintResults(matches)
-}
-
-func EvaluateFileStreamsSequence(expression string, filenames []string, printer Printer) error {
-
-	node, err := treeCreator.ParsePath(expression)
-	if err != nil {
-		return err
-	}
-
-	for _, filename := range filenames {
-		reader, err := readStream(filename)
-		if err != nil {
-			return err
-		}
-		err = EvaluateStream(filename, reader, node, printer)
-		if err != nil {
-			return err
-		}
-
-		switch reader := reader.(type) {
-		case *os.File:
-			safelyCloseFile(reader)
-		}
-	}
-	return nil
-}
-
 // func safelyRenameFile(from string, to string) {
 // 	if renameError := os.Rename(from, to); renameError != nil {
 // 		log.Debugf("Error renaming from %v to %v, attempting to copy contents", from, to)