fix: use latest version returned by goproxy instead of manually findi…

…ng latest (#17)

command.go

@@ -2,6 +2,7 @@ package libyear
 
 import (
 	"context"
+	"errors"
 	"log"
 	"os"
 	"slices"
@@ -57,7 +58,7 @@ func (c Command) Run(ctx context.Context) error {
 	mainModule.Time = time.Now()
 	if !c.optionIsSet(OptionIncludeIndirect) {
 		// Filter out indirect.
-		modules = slices.DeleteFunc(modules, func(module *internal.Module) bool { return module.IsIndirect })
+		modules = slices.DeleteFunc(modules, func(module *internal.Module) bool { return module.Indirect })
 	}
 
 	group, _ := c.newErrGroup(ctx)
@@ -70,7 +71,7 @@ func (c Command) Run(ctx context.Context) error {
 	}
 	// Remove skipped modules.
 	if c.optionIsSet(OptionSkipFresh) {
-		modules = slices.DeleteFunc(modules, func(module *internal.Module) bool { return module.IsFresh })
+		modules = slices.DeleteFunc(modules, func(module *internal.Module) bool { return module.Skipped })
 	}
 
 	// Aggregate results for main module.
@@ -93,7 +94,21 @@ const secondsInYear = float64(365 * 24 * 60 * 60)
 
 func (c Command) runForModule(module *internal.Module) error {
 	// We skip this module, unless we get to the end and manage to calculate libyear.
-	module.IsFresh = true
+	module.Skipped = true
+
+	// Fetch latest.
+	latest, err := c.repo.GetLatestInfo(module.Path)
+	if err != nil {
+		return err
+	}
+	// It returns -1 (smaller), 0 (larger), or 1 (greater) when compared.
+	if module.Version.Compare(latest.Version) != -1 {
+		module.Latest = module
+		module.Time = latest.Time
+		return nil
+	}
+	module.Latest = latest
+
 	// Since we're parsing the go.mod file directly, we might need to fetch the Module.Time.
 	if module.Time.IsZero() {
 		fetchedModule, err := c.repo.GetInfo(module.Path, module.Version)
@@ -102,65 +117,60 @@ func (c Command) runForModule(module *internal.Module) error {
 		}
 		module.Time = fetchedModule.Time
 	}
-	// Fetch all versions.
+
+	// The following calculations are based on https://ericbouwers.github.io/papers/icse15.pdf.
+	module.Libyear = calculateLibyear(module, latest)
+	if c.optionIsSet(OptionShowReleases) {
+		versions, err := c.getVersions(module)
+		if err == errNoVersions {
+			log.Printf("WARN: module '%s' does not have any versions", module.Path)
+			return nil
+		}
+		module.ReleasesDiff = calculateReleases(module, latest, versions)
+	}
+	if c.optionIsSet(OptionShowVersions) {
+		module.VersionsDiff = calculateVersions(module, latest)
+	}
+
+	module.Skipped = false
+	return nil
+}
+
+var errNoVersions = errors.New("no versions found")
+
+func (c Command) getVersions(module *internal.Module) ([]*semver.Version, error) {
 	versions, err := c.repo.GetVersions(module.Path)
 	if err != nil {
-		return err
+		return nil, err
 	}
 	if len(versions) == 0 {
 		if module.Version.Prerelease() == "" {
-			log.Printf("WARN: module '%s' does not have any versions", module.Path)
-			return nil
+			return nil, errNoVersions
 		}
 		// Try fetching the versions from deps.dev.
 		// Go list does not list prerelease versions, which is fine,
 		// unless we're dealing with a prerelease version ourselves.
 		versions, err = c.fallbackVersions.GetVersions(module.Path)
 		if err != nil {
-			return err
+			return nil, err
 		}
 		// Check again.
 		if len(versions) == 0 {
-			log.Printf("WARN: module '%s' does not have any versions", module.Path)
-			return nil
+			return nil, errNoVersions
 		}
 	}
 	sort.Sort(semver.Collection(versions))
-
-	latestVersion := versions[len(versions)-1]
-	// It returns -1 (smaller), 0 (larger), or 1 (greater) when compared.
-	if module.Version.Compare(latestVersion) != -1 {
-		module.Latest = module
-		return nil
-	}
-	// Fetch latest.
-	latest, err := c.repo.GetInfo(module.Path, latestVersion)
-	if err != nil {
-		return err
-	}
-	module.Latest = latest
-
-	// The following calculations are based on https://ericbouwers.github.io/papers/icse15.pdf.
-	module.Libyear = calculateLibyear(module, latest)
-	if c.optionIsSet(OptionShowReleases) {
-		module.ReleasesDiff = calculateReleases(module, versions)
-	}
-	if c.optionIsSet(OptionShowVersions) {
-		module.VersionsDiff = calculateVersions(module, latest)
-	}
-
-	module.IsFresh = false
-	return nil
+	return versions, nil
 }
 
 func calculateLibyear(module, latest *internal.Module) float64 {
 	diff := latest.Time.Sub(module.Time)
 	return diff.Seconds() / secondsInYear
 }
 
-func calculateReleases(module *internal.Module, versions []*semver.Version) int {
+func calculateReleases(module, latest *internal.Module, versions []*semver.Version) int {
 	currentIndex := slices.IndexFunc(versions, func(v *semver.Version) bool { return module.Version.Equal(v) })
-	latestIndex := len(versions) - 1
+	latestIndex := slices.IndexFunc(versions, func(v *semver.Version) bool { return latest.Version.Equal(v) })
 	// Example:
 	// v:  v1 | v2 | v3 | v4
 	// i:  0    1    2    3   > len == 4

command_test.go

@@ -69,22 +69,27 @@ func TestCommand_calculateLibyear(t *testing.T) {
 func TestCommand_calculateReleases(t *testing.T) {
 	tests := []struct {
 		CurrentVersion string
+		LatestVersion  string
 		Versions       []string
 		Expected       int
 	}{
 		{
 			CurrentVersion: "v0.9.0",
+			LatestVersion:  "v1.0.0",
 			Versions: []string{
 				"v0.9.0",
 				"v0.9.1",
 				"v0.9.2",
 				"v0.10.0",
 				"v1.0.0",
+				"v2.0.0-incompatible1",
+				"v2.0.0-incompatible2",
 			},
 			Expected: 4,
 		},
 		{
 			CurrentVersion: "v0.10.0",
+			LatestVersion:  "v1.0.0",
 			Versions: []string{
 				"v0.9.1",
 				"v0.9.2",
@@ -95,6 +100,7 @@ func TestCommand_calculateReleases(t *testing.T) {
 		},
 		{
 			CurrentVersion: "v1.0.0",
+			LatestVersion:  "v1.0.0",
 			Versions: []string{
 				"v0.9.2",
 				"v0.10.0",
@@ -104,6 +110,7 @@ func TestCommand_calculateReleases(t *testing.T) {
 		},
 		{
 			CurrentVersion: "v1.0.0",
+			LatestVersion:  "v1.0.0",
 			Versions: []string{
 				"v1.0.0",
 			},
@@ -118,6 +125,7 @@ func TestCommand_calculateReleases(t *testing.T) {
 			}
 			actual := calculateReleases(
 				&internal.Module{Version: semver.MustParse(test.CurrentVersion)},
+				&internal.Module{Version: semver.MustParse(test.LatestVersion)},
 				versions)
 			assert.Equal(t, test.Expected, actual)
 		})
@@ -193,10 +201,11 @@ func TestCommand_Fallback(t *testing.T) {
 				semver.MustParse("v1.0.0"),
 				semver.MustParse("v2.0.0"),
 			},
-			getInfoResponse: &internal.Module{},
+			getInfoResponse:   &internal.Module{},
+			getLatestResponse: &internal.Module{Version: semver.MustParse("v2.0.0")},
 		}
 		versionsGetter := &mockVersionsGetter{}
-		cmd := Command{repo: modulesRepo, fallbackVersions: versionsGetter}
+		cmd := Command{repo: modulesRepo, fallbackVersions: versionsGetter, opts: OptionShowReleases}
 
 		err := cmd.runForModule(&internal.Module{Version: semver.MustParse("v1.0.0")})
 
@@ -208,9 +217,10 @@ func TestCommand_Fallback(t *testing.T) {
 		modulesRepo := &mockModulesRepo{
 			getVersionsResponse: []*semver.Version{},
 			getInfoResponse:     &internal.Module{},
+			getLatestResponse:   &internal.Module{Version: semver.MustParse("v2.0.0")},
 		}
 		versionsGetter := &mockVersionsGetter{}
-		cmd := Command{repo: modulesRepo, fallbackVersions: versionsGetter}
+		cmd := Command{repo: modulesRepo, fallbackVersions: versionsGetter, opts: OptionShowReleases}
 
 		// Don't call fallback if a version does not contain a prerelease.
 		// We only expect GOPROXY to lack versions list when no semver version was released by a module.
@@ -232,6 +242,7 @@ type mockModulesRepo struct {
 	getVersionsCalledTimes int
 	getVersionsResponse    []*semver.Version
 	getInfoResponse        *internal.Module
+	getLatestResponse      *internal.Module
 }
 
 func (m *mockModulesRepo) GetVersions(string) ([]*semver.Version, error) {
@@ -248,7 +259,7 @@ func (m *mockModulesRepo) GetInfo(string, *semver.Version) (*internal.Module, er
 }
 
 func (m *mockModulesRepo) GetLatestInfo(string) (*internal.Module, error) {
-	panic("implement me")
+	return m.getLatestResponse, nil
 }
 
 type mockVersionsGetter struct {

internal/go_list.go

@@ -49,22 +49,23 @@ func (e *GoListExecutor) GetLatestInfo(path string) (*Module, error) {
 	return e.getInfo(path, nil, true)
 }
 
+// Fetch module details.
 func (e *GoListExecutor) getInfo(path string, version *semver.Version, latest bool) (*Module, error) {
 	var versionStr string
 	if latest {
 		versionStr = "latest"
 	} else {
-		versionStr = version.String()
+		versionStr = "v" + version.String()
 	}
 	// Try loading from cache.
-	if e.cache != nil {
+	if version != nil && e.cache != nil {
 		m, loaded := e.cache.Load(path, version)
 		if loaded {
 			return m, nil
 		}
 	}
 	// Fetch module details.
-	out, err := e.exec(path + "@v" + versionStr)
+	out, err := e.exec(path + "@" + versionStr)
 	if err != nil {
 		return nil, err
 	}

internal/go_proxy.go

@@ -64,7 +64,7 @@ func (c *GoProxyClient) GetLatestInfo(path string) (*Module, error) {
 
 func (c *GoProxyClient) getInfo(path string, version *semver.Version, latest bool) (*Module, error) {
 	// Try loading from cache.
-	if c.cache != nil {
+	if version != nil && c.cache != nil {
 		m, loaded := c.cache.Load(path, version)
 		if loaded {
 			return m, nil

internal/module.go

@@ -19,10 +19,10 @@ type Module struct {
 	Version *semver.Version `json:"Version"`
 	Time    time.Time       `json:"Time"`
 
-	IsIndirect bool    `json:"-"`
-	IsFresh    bool    `json:"-"`
-	Latest     *Module `json:"-"`
-	Libyear    float64 `json:"-"`
+	Indirect bool    `json:"-"`
+	Skipped  bool    `json:"-"`
+	Latest   *Module `json:"-"`
+	Libyear  float64 `json:"-"`
 	// ReleasesDiff is the number of release versions between latest and current.
 	ReleasesDiff int `json:"-"`
 	// VersionsDiff is an array of 3 elements: major, minor and patch versions.
@@ -64,9 +64,9 @@ func ReadGoMod(content []byte) (mainModule *Module, modules []*Module, err error
 			return nil, nil, err
 		}
 		modules = append(modules, &Module{
-			Path:       require.Mod.Path,
-			Version:    version,
-			IsIndirect: require.Indirect,
+			Path:     require.Mod.Path,
+			Version:  version,
+			Indirect: require.Indirect,
 		})
 	}
 	if modFile.Module == nil {

test/inputs/responses.json

@@ -218,12 +218,17 @@
     "Version": "v1.3.2",
     "Time": "2023-06-08T06:14:45Z"
   },
+  "github.com/!burnt!sushi/toml": {
+    "Path": "github.com/BurntSushi/toml",
+    "Version": "v2.0.0-experimental",
+    "Time": "2021-08-05T05:14:45Z"
+  },
   "github.com/!burnt!sushi/toml/@latest": {
     "Path": "github.com/BurntSushi/toml",
     "Version": "v1.3.2",
     "Time": "2023-06-08T06:14:45Z"
   },
-  "github.com/!burnt!sushi/toml/@v/list": "v0.1.0\nv0.2.0\nv0.3.0\nv0.3.1\nv0.4.0\nv0.4.1\nv1.0.0\nv1.1.0\nv1.2.0\nv1.2.1\nv1.3.0\nv1.3.1\nv1.3.2",
+  "github.com/!burnt!sushi/toml/@v/list": "v0.1.0\nv0.2.0\nv0.3.0\nv0.3.1\nv0.4.0\nv0.4.1\nv1.0.0\nv1.1.0\nv1.2.0\nv1.2.1\nv1.3.0\nv1.3.1\nv1.3.2\nv2.0.0-experimental",
   "github.com/test/test/@latest": "v1.0.0",
   "github.com/test/test/@v/v1.0.0.mod": "./test/inputs/go.mod"
 }