Implement #242: Made the fuzzy filter configurable

README.md

@@ -58,13 +58,15 @@ Not only can you select multiple lines one by one, you can select a range of lin
 
 ## Select Filters
 
-Different types of filters are available. Default is case-insensitive filter, so lines with any case will match. You can toggle between IgnoreCase, CaseSensitive, SmartCase and RegExp filters. 
+Different types of filters are available. Default is case-insensitive filter, so lines with any case will match. You can toggle between IgnoreCase, CaseSensitive, SmartCase RegExp and Fuzzy filters. 
 
 The SmartCase filter uses case-*insensitive* matching when all of the queries are lower case, and case-*sensitive* matching otherwise.
 
 The RegExp filter allows you to use any valid regular expression to match lines
 
-![Executed `ps aux | peco`, then typed `google`, which matches the Chrome.app under IgnoreCase filter type. Whenyou change it to Regexp filter, this is no longer the case. But you can type `(?i)google` instead to toggle case-insensitive mode](http://peco.github.io/images/peco-demo-matcher.gif)
+The Fuzzy filter allows you to find matches using partial patterns. For example, when searching for `ALongString`, you can enable the Fuzzy filter and search `ALS` to find it. The Fuzzy filter uses smart case search like the SmartCase filter. The Fuzzy filter is not enabled by default, but can be enabled using option `--enable-fuzzy`.
+
+![Executed `ps aux | peco`, then typed `google`, which matches the Chrome.app under IgnoreCase filter type. When you change it to Regexp filter, this is no longer the case. But you can type `(?i)google` instead to toggle case-insensitive mode](http://peco.github.io/images/peco-demo-matcher.gif)
 
 ## Selectable Layout
 
@@ -158,9 +160,13 @@ Changes how peco interprets incoming data. When this flag is set, you may insert
 
 Specifies the initial line position upon start up. E.g. If you want to start out with the second line selected, set it to "1" (because the index is 0 based)
 
-### --initial-filter `IgnoreCase|CaseSensitive|SmartCase|Regexp`
+### --fuzzy-filter `enabled|disabled`
 
-Specifies the initial filter to use upon start up. You should specify the name of the filter like `IgnoreCase`, `CaseSensitive`, `SmartCase` and `Regexp`. Default is `IgnoreCase`.
+Make the Fuzzy filter available. The command line option can override the value in the configuration file. Default is `disabled`.
+
+### --initial-filter `IgnoreCase|CaseSensitive|SmartCase|Regexp|Fuzzy`
+
+Specifies the initial filter to use upon start up. You should specify the name of the filter like `IgnoreCase`, `CaseSensitive`, `SmartCase`, `Regexp` and `Fuzzy` (if enabled). Default is `IgnoreCase`.
 
 ### --prompt
 
@@ -217,9 +223,13 @@ You can change the query line's prompt, which is `QUERY>` by default.
 
 *InitialMatcher* has been deprecated. Please use `InitialFilter` instead.
 
+### FuzzyFilter
+
+Set to `enabled` to make the Fuzzy filter available. Default is `disabled`.
+
 ### InitialFilter
 
-Specifies the filter name to start peco with. You should specify the name of the filter, such as `IgnoreCase`, `CaseSensitive`, `SmartCase` and `Regexp`
+Specifies the filter name to start peco with. You should specify the name of the filter, such as `IgnoreCase`, `CaseSensitive`, `SmartCase`, `Regexp` and `Fuzzy` (if [enabled](#FuzzyFilter)).
 
 ### StickySelection
 
@@ -473,7 +483,7 @@ For now, styles of following 5 items can be customized in `config.json`.
 
 This is an experimental feature. Please note that some details of this specification may change
 
-By default `peco` comes with `IgnoreCase`, `CaseSensitive`, `SmartCase` and `Regexp` filters, but since v0.1.3, it is possible to create your own custom filter.
+By default `peco` comes with `IgnoreCase`, `CaseSensitive`, `SmartCase`, `Regexp` and `Fuzzy` filters, but since v0.1.3, it is possible to create your own custom filter.
 
 The filter will be executed via  `Command.Run()` as an external process, and it will be passed the query values in the command line, and the original unaltered buffer is passed via `os.Stdin`. Your filter must perform the matching, and print out to `os.Stdout` matched lines. You filter MAY be called multiple times if the buffer
 given to peco is big enough. See `BufferThreshold` below.

config.go

@@ -25,6 +25,7 @@ func (c *Config) Init() error {
 	c.Style.Init()
 	c.Prompt = "QUERY>"
 	c.Layout = LayoutTypeTopDown
+	c.FuzzyFilter = OptionDisabled
 	return nil
 }
 

config_test.go

@@ -47,6 +47,7 @@ func TestReadRC(t *testing.T) {
 		InitialMatcher: IgnoreCaseMatch,
 		Layout:         DefaultLayoutType,
 		Prompt:         "[peco]",
+		FuzzyFilter:    "disabled",
 		Style: StyleSet{
 			Matched: Style{
 				fg: termbox.ColorCyan | termbox.AttrBold,

filter.go

@@ -433,9 +433,8 @@ func NewFuzzyFilter() *RegexpFilter {
 		return []string{"i"}
 	})
 	rf.quotemeta = true
-	rf.name = "FuzzySearch"
+	rf.name = FuzzyFilter
 	rf.queryTrans = queryTransformerFunc(func(q string) string {
-		// Assume that all characters are runes
 		qr := []rune(q)
 		res := make([]rune, 5*len(qr))
 		i := 0

interface.go

@@ -46,6 +46,11 @@ const (
 	RegexpMatch        = "Regexp"
 )
 
+// Filter names, used in the config file
+const (
+	FuzzyFilter = "Fuzzy"
+)
+
 // lineIDGenerator defines an interface for things that generate
 // unique IDs for lines used within peco.
 type lineIDGenerator interface {
@@ -56,6 +61,11 @@ type idgen struct {
 	ch chan uint64
 }
 
+const (
+	OptionEnabled  = "enabled"
+	OptionDisabled = "disabled"
+)
+
 // Peco is the global object containing everything required to run peco.
 // It also contains the global state of the program.
 type Peco struct {
@@ -74,6 +84,7 @@ type Peco struct {
 	enableSep               bool // Enable parsing on separators
 	filters                 FilterSet
 	idgen                   *idgen
+	enableFuzzy             bool
 	initialFilter           string
 	initialQuery            string   // populated if --query is specified
 	inputseq                Inputseq // current key sequence (just the names)
@@ -343,6 +354,7 @@ type Config struct {
 	Keymap              map[string]string `json:"Keymap"`
 	Matcher             string            `json:"Matcher"`        // Deprecated.
 	InitialMatcher      string            `json:"InitialMatcher"` // Use this instead of Matcher
+	FuzzyFilter         string            `json:"FuzzyFilter"`
 	InitialFilter       string            `json:"InitialFilter"`
 	Style               StyleSet          `json:"Style"`
 	Prompt              string            `json:"Prompt"`
@@ -475,6 +487,7 @@ type CLIOptions struct {
 	OptEnableNullSep  bool   `long:"null" description:"expect NUL (\\0) as separator for target/output"`
 	OptInitialIndex   int    `long:"initial-index" description:"position of the initial index of the selection (0 base)"`
 	OptInitialMatcher string `long:"initial-matcher" description:"specify the default matcher (deprecated)"`
+	OptFuzzyFilter    string `short:"z" long:"fuzzy-filter" description:"enable/disable the Fuzzy filter"`
 	OptInitialFilter  string `long:"initial-filter" description:"specify the default filter"`
 	OptPrompt         string `long:"prompt" description:"specify the prompt string"`
 	OptLayout         string `long:"layout" description:"layout to be used 'top-down' or 'bottom-up'. default is 'top-down'"`

peco.go

@@ -500,6 +500,20 @@ func (p *Peco) ApplyConfig(opts CLIOptions) error {
 	p.bufferSize = opts.OptBufferSize
 	p.selectOneAndExit = opts.OptSelect1
 	p.initialQuery = opts.OptQuery
+	// Option EnableFuzzy is a string to allow overriding the value on the command line
+	fuzzyFilter := opts.OptFuzzyFilter
+	if len(fuzzyFilter) <= 0 {
+		fuzzyFilter = p.config.FuzzyFilter
+	}
+	if len(fuzzyFilter) > 0 {
+		if fuzzyFilter == OptionEnabled {
+			p.enableFuzzy = true
+		} else if fuzzyFilter == OptionDisabled {
+			p.enableFuzzy = false
+		} else {
+			return errors.Errorf("Unexpected value for FuzzyFilter option: %v (expected %v/%v)", fuzzyFilter, OptionEnabled, OptionDisabled)
+		}
+	}
 	p.initialFilter = opts.OptInitialFilter
 	if len(p.initialFilter) <= 0 {
 		p.initialFilter = p.config.InitialFilter
@@ -507,6 +521,9 @@ func (p *Peco) ApplyConfig(opts CLIOptions) error {
 	if len(p.initialFilter) <= 0 {
 		p.initialFilter = opts.OptInitialMatcher
 	}
+	if len(p.initialFilter) > 0 && !p.enableFuzzy && p.initialFilter == FuzzyFilter {
+		return errors.New("Fuzzy filter is not enabled, can not set it to the initial filter.")
+	}
 
 	if err := p.populateCommandList(); err != nil {
 		return errors.Wrap(err, "failed to populate command list")
@@ -566,7 +583,9 @@ func (p *Peco) populateFilters() error {
 	p.filters.Add(NewCaseSensitiveFilter())
 	p.filters.Add(NewSmartCaseFilter())
 	p.filters.Add(NewRegexpFilter())
-	p.filters.Add(NewFuzzyFilter())
+	if p.enableFuzzy {
+		p.filters.Add(NewFuzzyFilter())
+	}
 
 	for name, c := range p.config.CustomFilter {
 		f := NewExternalCmdFilter(name, c.Cmd, c.Args, c.BufferThreshold, p.idgen, p.enableSep)

peco_test.go

@@ -197,6 +197,44 @@ func TestGHIssue331(t *testing.T) {
 	}
 }
 
+func TestConfigFuzzyFilter(t *testing.T) {
+	var opts CLIOptions
+	p := newPeco()
+
+	// Ensure that it's possible to enable the Fuzzy filter
+	opts.OptFuzzyFilter = "enabled"
+	if !assert.NoError(t, p.ApplyConfig(opts), "p.ApplyConfig should succeed") {
+		return
+	}
+	if !assert.Equal(t, true, p.enableFuzzy, "p.enableFuzzy should be equal to opts.OptEnableFuzzy") {
+		return
+	}
+	opts.OptFuzzyFilter = "abc"
+	if !assert.Error(t, p.ApplyConfig(opts), "p.ApplyConfig should not succeed") {
+		return
+	}
+}
+
+func TestConfigInitialFilterFuzzy(t *testing.T) {
+	var opts CLIOptions
+	p := newPeco()
+
+	// If Fuzzy is not enabled, initialFilter=Fuzzy should cause peco to fail
+	opts.OptFuzzyFilter = "disabled"
+	opts.OptInitialFilter = "Fuzzy"
+	if !assert.Error(t, p.ApplyConfig(opts), "p.ApplyConfig should not succeed") {
+		return
+	}
+	// If Fuzzy is enabled, it should be possible to set the initial filter to Fuzzy
+	opts.OptFuzzyFilter = "enabled"
+	if !assert.NoError(t, p.ApplyConfig(opts), "p.ApplyConfig should succeed") {
+		return
+	}
+	if !assert.Equal(t, true, p.enableFuzzy, "p.enableFuzzy should be equal to opts.OptEnableFuzzy") {
+		return
+	}
+}
+
 func TestApplyConfig(t *testing.T) {
 	// XXX We should add all the possible configurations that needs to be
 	// propagated to Peco from config