Switch to JaroWinkler distance and reweight package search scores (#2840)

fix(query): use JaroWinkler distance and reweight metric components

Switch from Hamming to JaroWinkler distance for package name matching,
as JaroWinkler handles variable-length strings and gives a prefix-match
bonus better suited to package search.

Reweight the score components from sim*0.50 + simDesc*0.20 + popularity*0.30
to sim*0.35 + simDesc*0.15 + popularity*0.50 to better surface popular
packages when name similarity is moderate.

Roll back the unreleased version target from 13.0.0 to 12.6.0 to align
with the next minor release after v12.5.7.

Fix scanner.Err() check in parseStdin to surface I/O errors that were
previously silently dropped.

main.go

@@ -18,7 +18,7 @@ import (
 )
 
 var (
-	yayVersion = "13.0.0"            // To be set by compiler.
+	yayVersion = "12.6.0"            // To be set by compiler.
 	localePath = "/usr/share/locale" // To be set by compiler.
 )
 

pkg/query/metric.go

@@ -52,7 +52,7 @@ func (a *abstractResults) GetMetric(pkg *abstractResult) float64 {
 		popularity = a.aurSortByMetric(pkg)
 	}
 
-	sim = sim*0.5 + simDesc*0.2 + popularity*0.3
+	sim = sim*0.35 + simDesc*0.15 + popularity*0.50
 
 	a.distanceCache[pkg.name] = sim
 

pkg/query/query_builder.go

@@ -181,7 +181,7 @@ func (s *SourceQueryBuilder) Execute(ctx context.Context, dbExecutor db.Executor
 
 	pkgS = RemoveInvalidTargets(s.logger, pkgS, s.targetMode)
 
-	metric := &metrics.Hamming{
+	metric := &metrics.JaroWinkler{
 		CaseSensitive: false,
 	}
 

pkg/query/query_builder_test.go

@@ -567,13 +567,13 @@ func TestSourceQueryBuilderSortByFields(t *testing.T) {
 			desc:      "sort-by-metric topdown",
 			sortBy:    "",
 			bottomUp:  false,
-			wantNames: []string{"yay", "yay-git", "ruby-yard"},
+			wantNames: []string{"yay", "ruby-yard", "yay-git"},
 		},
 		{
 			desc:      "sort-by-metric bottomup",
 			sortBy:    "",
 			bottomUp:  true,
-			wantNames: []string{"ruby-yard", "yay-git", "yay"},
+			wantNames: []string{"yay-git", "ruby-yard", "yay"},
 		},
 	}
 
@@ -599,6 +599,76 @@ func TestSourceQueryBuilderSortByFields(t *testing.T) {
 	}
 }
 
+func TestSourceQueryBuilderChromeRanking(t *testing.T) {
+	t.Parallel()
+
+	mockDB := &mock.DBExecutor{
+		ReposFn: func() []string {
+			return []string{"extra"}
+		},
+		SyncPackagesFn: func(pkgs ...string) []mock.IPackage {
+			return nil
+		},
+		LocalPackageFn: func(string) mock.IPackage {
+			return nil
+		},
+	}
+
+	mockAUR := &mockaur.MockAUR{
+		GetFn: func(ctx context.Context, query *aur.Query) ([]aur.Pkg, error) {
+			return []aur.Pkg{
+				{
+					Description: "The popular web browser by Google (Stable Channel)",
+					Name:        "google-chrome",
+					NumVotes:    2351,
+					Popularity:  13.24,
+					PackageBase: "google-chrome",
+					Version:     "149.0.7827.53-1",
+				},
+				{
+					Description: "Extract Android APKs for running in Chrome OS OR Chrome in OS X, Linux and Windows",
+					Name:        "chromeos-apk-git",
+					NumVotes:    37,
+					Popularity:  0.00,
+					PackageBase: "chromeos-apk-git",
+					Version:     "20201218.r129.f13a94d-1",
+				},
+				{
+					Description: "External extension updater for Chromium based browsers",
+					Name:        "chromexup",
+					NumVotes:    5,
+					Popularity:  0.00,
+					PackageBase: "chromexup",
+					Version:     "0.5.4-5",
+				},
+				{
+					Description: "Standalone server that implements the W3C WebDriver standard (for goog",
+					Name:        "chromedriver",
+					NumVotes:    52,
+					Popularity:  0.50,
+					PackageBase: "chromedriver",
+					Version:     "149.0.7827.54-1",
+				},
+			}, nil
+		},
+	}
+
+	w := &strings.Builder{}
+	queryBuilder := NewSourceQueryBuilder(mockAUR,
+		text.NewLogger(w, io.Discard, strings.NewReader(""), false, "test"),
+		"", parser.ModeAny, "", false,
+		false, false)
+
+	queryBuilder.Execute(context.Background(), mockDB, []string{"chrome"})
+
+	gotNames := make([]string, len(queryBuilder.results))
+	for i, result := range queryBuilder.results {
+		gotNames[i] = result.name
+	}
+
+	assert.Equal(t, []string{"google-chrome", "chromedriver", "chromeos-apk-git", "chromexup"}, gotNames)
+}
+
 func newYayQueryBuilderMocks() (*mock.DBExecutor, *mockaur.MockAUR) {
 	mockDB := &mock.DBExecutor{
 		ReposFn: func() []string {

pkg/settings/migrations.go

@@ -56,7 +56,7 @@ func (migration *configSortByMigration) Do(config *Configuration) bool {
 }
 
 func (migration *configSortByMigration) TargetVersion() string {
-	return "13.0.0"
+	return "12.6.0"
 }
 
 func DefaultMigrations() []configMigration {

pkg/settings/migrations_test.go

@@ -188,37 +188,37 @@ func TestSortByMigration(t *testing.T) {
 		{
 			desc: "to upgrade",
 			testConfig: &Configuration{
-				Version: "12.9.0",
+				Version: "12.5.7",
 				SortBy:  "name",
 			},
-			newVersion: "13.0.0",
+			newVersion: "12.6.0",
 			wantSave:   true,
 		},
 		{
 			desc: "to upgrade-git",
 			testConfig: &Configuration{
-				Version: "12.9.0.r7.g6f60892",
+				Version: "12.3.0.r7.g6f60892",
 				SortBy:  "votes",
 			},
-			newVersion: "13.0.0",
+			newVersion: "12.6.0",
 			wantSave:   true,
 		},
 		{
 			desc: "to not upgrade",
 			testConfig: &Configuration{
-				Version: "12.9.0",
+				Version: "12.2.0",
 				SortBy:  "",
 			},
-			newVersion: "13.0.0",
+			newVersion: "12.6.0",
 			wantSave:   false,
 		},
 		{
 			desc: "to not upgrade - target version",
 			testConfig: &Configuration{
-				Version: "13.0.0",
+				Version: "12.6.0",
 				SortBy:  "name",
 			},
-			newVersion: "13.0.0",
+			newVersion: "12.6.0",
 			wantSave:   false,
 		},
 		{

pkg/settings/parser/parser.go

@@ -613,6 +613,10 @@ func (a *Arguments) parseStdin() error {
 		a.AddTarget(scanner.Text())
 	}
 
+	if err := scanner.Err(); err != nil {
+		return err
+	}
+
 	return os.Stdin.Close()
 }