feat: add fuzzy suggestion mode

Signed-off-by: y-rabie <[email protected]>

Author: y-rabie

README.md

@@ -463,6 +463,7 @@ You can now override the context portForward default address configuration by se
       showTime: false
     # Define how suggestions are made.
     # "PREFIX": typed text is considered a prefix, sorts suggestions alphabetically. Default mode.
+    # "FUZZY": typed text is fuzzy-matched against suggestions, sorted by Levenshtein distance (but only character additions are considered as possible string edits).
     # "LONGEST_PREFIX": typed text is considered a prefix, sorts suggestions by how much of the typed text they match; if equal, it falls back to alphabetical order.
     # "LONGEST_SUBSTRING": typed text is considered a substring, sorts suggestions by how much of the typed text they match; if equal, it falls back to alphabetical order.
     suggestionMode: PREFIX

cmd/root.go

@@ -261,7 +261,7 @@ func initK9sFlags() {
 		k9sFlags.SuggestionMode,
 		"suggestion-mode",
 		string(config.DefaultSuggestionMode),
-		"Set autocompletion suggestion mode (PREFIX, LONGEST_PREFIX, LONGEST_SUBSTRING)",
+		"Set autocompletion suggestion mode (PREFIX, FUZZY, LONGEST_PREFIX, LONGEST_SUBSTRING)",
 	)
 	rootCmd.Flags()
 }

go.mod

@@ -16,6 +16,7 @@ require (
 	github.com/fvbommel/sortorder v1.1.0
 	github.com/go-errors/errors v1.5.1
 	github.com/itchyny/gojq v0.12.17
+	github.com/lithammer/fuzzysearch v1.1.8
 	github.com/lmittmann/tint v1.0.7
 	github.com/mattn/go-colorable v0.1.14
 	github.com/mattn/go-runewidth v0.0.16

go.sum

@@ -1372,6 +1372,8 @@ github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de h1:9TO3cAIGXtEhn
 github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de/go.mod h1:zAbeS9B/r2mtpb6U+EI2rYA5OAXxsYw6wTamcNW+zcE=
 github.com/lithammer/dedent v1.1.0 h1:VNzHMVCBNG1j0fh3OrsFRkVUwStdDArbgBWoPAffktY=
 github.com/lithammer/dedent v1.1.0/go.mod h1:jrXYCQtgg0nJiN+StA2KgR7w6CiQNv9Fd/Z9BP0jIOc=
+github.com/lithammer/fuzzysearch v1.1.8 h1:/HIuJnjHuXS8bKaiTMeeDlW2/AyIWk2brx1V8LFgLN4=
+github.com/lithammer/fuzzysearch v1.1.8/go.mod h1:IdqeyBClc3FFqSzYq/MXESsS4S0FsZ5ajtkr5xPLts4=
 github.com/lmittmann/tint v1.0.7 h1:D/0OqWZ0YOGZ6AyC+5Y2kD8PBEzBk6rFHVSfOqCkF9Y=
 github.com/lmittmann/tint v1.0.7/go.mod h1:HIS3gSy7qNwGCj+5oRjAutErFBl4BzdQP6cJZ0NfMwE=
 github.com/logrusorgru/aurora v2.0.3+incompatible h1:tOpm7WcpBTn4fjmVfgpQq0EfczGlG91VSDkswnjF5A8=

internal/config/types.go

@@ -18,6 +18,7 @@ type SuggestionMode string
 
 const (
 	SuggestionModePrefix           SuggestionMode = "PREFIX"
+	SuggestionModeFuzzy            SuggestionMode = "FUZZY"
 	SuggestionModeLongestPrefix    SuggestionMode = "LONGEST_PREFIX"
 	SuggestionModeLongestSubstring SuggestionMode = "LONGEST_SUBSTRING"
 )

internal/ui/prompt.go

@@ -234,6 +234,37 @@ func (p *Prompt) update(text, suggestion string) {
 	p.write(text, suggestion)
 }
 
+func (p *Prompt) getSuggestionCharIdxRanges(lastWord, suggest string) [][]int {
+	switch p.app.Config.K9s.SuggestionMode {
+	case string(config.SuggestionModeFuzzy):
+		idxRanges := make([][]int, 0, len(lastWord))
+		latestIdx := -1
+		for _, char := range lastWord {
+			// Find the character within the suggest, but only starting after where the last character was found.
+			foundIdx := strings.IndexRune(suggest[latestIdx+1:], char)
+			// This should never happen if we reached here, but just guarding.
+			if foundIdx == -1 {
+				return nil
+			}
+			// Offset by the cutoff length of the string from previous iterations.
+			foundIdx += latestIdx + 1
+			idxRanges = append(idxRanges, []int{foundIdx, foundIdx + 1})
+			latestIdx = foundIdx
+		}
+		return idxRanges
+	default:
+		// Get indices of where the last word of text lie within the suggestion.
+		// Could be anywhere if LONGEST_SUBSTRING mode suggestion is used.
+		// Otherwise at 0 for PREFIX/LONGEST_PREFIX suggestion modes.
+		startIdx := strings.Index(suggest, lastWord)
+		endIdx := startIdx + len(lastWord)
+		if startIdx == -1 {
+			return nil
+		}
+		return [][]int{{startIdx, endIdx}}
+	}
+}
+
 func (p *Prompt) write(text, suggest string) {
 	p.mx.Lock()
 	defer p.mx.Unlock()
@@ -250,20 +281,19 @@ func (p *Prompt) write(text, suggest string) {
 			written = strings.Join(words[0:len(words)-1], " ") + " "
 			lastWord := words[len(words)-1]
 
-			// Get indices of where the last word of text lie within the suggestion.
-			// Could be anywhere if LONGEST_SUBSTRING mode suggestion is used.
-			// Otherwise at 0 for PREFIX/LONGEST_PREFIX suggestion modes.
-			startIdx := strings.Index(suggest, lastWord)
-			endIdx := startIdx + len(lastWord)
-
-			if startIdx != -1 {
-				written += fmt.Sprintf("[%s::-]%s[%s::-]%s[%s::-]%s",
-					p.styles.Prompt().SuggestColor, suggest[0:startIdx],
-					p.styles.Prompt().FgColor, suggest[startIdx:endIdx],
-					p.styles.Prompt().SuggestColor, suggest[endIdx:],
-				)
+			if idxRanges := p.getSuggestionCharIdxRanges(lastWord, suggest); idxRanges != nil {
+				fmt.Println(idxRanges)
+				written += fmt.Sprintf("[%s::-]%s", p.styles.Prompt().SuggestColor, suggest[0:idxRanges[0][0]])
+				for i, idxRange := range idxRanges {
+					if i > 0 {
+						written += fmt.Sprintf("[%s::-]%s", p.styles.Prompt().SuggestColor, suggest[idxRanges[i-1][1]:idxRanges[i][0]])
+					}
+					written += fmt.Sprintf("[%s::-]%s", p.styles.Prompt().FgColor, suggest[idxRange[0]:idxRange[1]])
+				}
+				written += fmt.Sprintf("[%s::-]%s", p.styles.Prompt().SuggestColor, suggest[idxRanges[len(idxRanges)-1][1]:])
 			} else {
-				// `lastWord` isn't found within suggest. Just append `lastWord` again.
+				// `lastWord` isn't found within suggest as per the configured
+				// `SuggestionMode`. Just append `lastWord` again.
 				written += lastWord
 			}
 

internal/view/app.go

@@ -221,8 +221,9 @@ func (a *App) suggestCommand() model.SuggestionFunc {
 			entries = append(entries, k)
 		}
 
-		// PREFIX suggestion mode:, all weights are set to 0, sort strings normally.
-		// LONGEST_PREFIX,LONGEST_SUBSTRING suggestion modes: sort based on weights and fallback to string sorting for equal weights.
+		// PREFIX suggestion mode: all weights are set to 0, sort strings normally.
+		// FUZZY,LONGEST_PREFIX,LONGEST_SUBSTRING suggestion modes: sort based on weights
+		// and fallback to string sorting for equal weights.
 		sort.SliceStable(entries, func(i, j int) bool {
 			if entriesMap[entries[i]] == entriesMap[entries[j]] {
 				return entries[i] < entries[j]

internal/view/cmd/helpers.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"github.com/derailed/k9s/internal/client"
+	"github.com/lithammer/fuzzysearch/fuzzy"
 )
 
 func ToLabels(s string) map[string]string {
@@ -30,21 +31,25 @@ func ToLabels(s string) map[string]string {
 
 // ShouldAddSuggest checks if a suggestion match the given command.
 func ShouldAddSuggest(suggestionMode, command, suggest string) float64 {
-	var searchCondition bool
+	var condition bool
 	var weight float64 = 0
 
 	switch suggestionMode {
-	case "LONGEST_SUBSTRING":
-		searchCondition = strings.Contains(suggest, command)
-		weight = float64(len(command)) / float64(len(suggest))
+	case "FUZZY":
+		// Weight is the inverse of the Levenshtein distance.
+		weight = 1 / float64(fuzzy.RankMatch(command, suggest))
+		condition = (weight != -1)
 	case "LONGEST_PREFIX":
-		searchCondition = strings.HasPrefix(suggest, command)
+		condition = strings.HasPrefix(suggest, command)
+		weight = float64(len(command)) / float64(len(suggest))
+	case "LONGEST_SUBSTRING":
+		condition = strings.Contains(suggest, command)
 		weight = float64(len(command)) / float64(len(suggest))
 	default:
-		searchCondition = strings.HasPrefix(suggest, command)
+		condition = strings.HasPrefix(suggest, command)
 	}
 
-	if command != suggest && searchCondition {
+	if condition {
 		return weight
 	}
 

internal/view/cmd/helpers_test.go

@@ -93,6 +93,49 @@ func TestSuggestSubCommandPrefix(t *testing.T) {
 	}
 }
 
+func TestSuggestSubCommandFuzzy(t *testing.T) {
+	namespaceNames := map[string]struct{}{
+		"kube-system":   {},
+		"kube-public":   {},
+		"default":       {},
+		"nginx-ingress": {},
+	}
+	contextNames := []string{"develop", "test", "pre", "prod"}
+
+	// The weights are: 1 / distance.
+	// Distance is the number of needed character additions.
+	tests := []struct {
+		Command     string
+		Suggestions map[string]float64
+	}{
+		{Command: "q", Suggestions: nil},
+		{Command: "xray  dp", Suggestions: nil},
+		{Command: "help  k", Suggestions: nil},
+		{Command: "ctx p", Suggestions: map[string]float64{"develop": 1.0 / 6.0, "pre": 1.0 / 2.0, "prod": 1.0 / 3.0}},
+		{Command: "ctx   p", Suggestions: map[string]float64{"develop": 1.0 / 6.0, "pre": 1.0 / 2.0, "prod": 1.0 / 3.0}},
+		{Command: "ctx pr", Suggestions: map[string]float64{"pre": 1.0, "prod": 1.0 / 2.0}},
+		{Command: "ctx pr", Suggestions: map[string]float64{"pre": 1.0, "prod": 1.0 / 2.0}},
+		{Command: "ctx", Suggestions: map[string]float64{" develop": 1.0 / 7.0, " pre": 1.0 / 3.0, " prod": 1.0 / 4.0, " test": 1.0 / 4.0}},
+		{Command: "ctx ", Suggestions: map[string]float64{"develop": 1.0 / 7.0, "pre": 1.0 / 3.0, "prod": 1.0 / 4.0, "test": 1.0 / 4.0}},
+		{Command: "context   d", Suggestions: map[string]float64{"develop": 1.0 / 6.0, "prod": 1.0 / 3.0}},
+		{Command: "contexts   t", Suggestions: map[string]float64{"test": 1.0 / 3.0}},
+		{Command: "po ", Suggestions: nil},
+		{Command: "po  x", Suggestions: map[string]float64{"nginx-ingress": 1.0 / 12.0}},
+		{Command: "po k", Suggestions: map[string]float64{"kube-public": 1.0 / 10.0, "kube-system": 1.0 / 10.0}},
+		{Command: "po  kube-", Suggestions: map[string]float64{"kube-public": 1.0 / 6.0, "kube-system": 1.0 / 6.0}},
+		// Fuzzy-specific testcases.
+		{Command: "ctx pd", Suggestions: map[string]float64{"prod": 1.0 / 2.0}},
+		{Command: "ctx dp", Suggestions: map[string]float64{"develop": 1.0 / 5.0}},
+		{Command: "ctx tt", Suggestions: map[string]float64{"test": 1.0 / 2.0}},
+		{Command: "po dlt", Suggestions: map[string]float64{"default": 1.0 / 4.0}},
+	}
+
+	for _, tt := range tests {
+		got := SuggestSubCommand("FUZZY", tt.Command, namespaceNames, contextNames)
+		assert.Equal(t, tt.Suggestions, got)
+	}
+}
+
 func TestSuggestSubCommandLongestPrefix(t *testing.T) {
 	namespaceNames := map[string]struct{}{
 		"kube-system":   {},