add install -u and -n flags

-u makes it upgrade all apps which can be upgraded, which is a common
operation

However, we don't want device.txt to run a full install + upgrade +
uninstall cycle again, as that's too slow. For that reason, introduce an
dry-run flag in install, so that we can check that -u would do the right
thing.

Fixes #22.

install.go

@@ -5,6 +5,7 @@ package main
 
 import (
 	"fmt"
+	"os"
 
 	"mvdan.cc/fdroidcl/adb"
 	"mvdan.cc/fdroidcl/fdroid"
@@ -15,27 +16,49 @@ var cmdInstall = &Command{
 	Short:     "Install or upgrade an app",
 }
 
+var (
+	installUpdates = cmdInstall.Fset.Bool("u", false, "Upgrade all installed apps")
+	installDryRun  = cmdInstall.Fset.Bool("n", false, "Only print the operations that would be done")
+)
+
 func init() {
 	cmdInstall.Run = runInstall
 }
 
 func runInstall(args []string) error {
-	if len(args) < 1 {
+	if *installUpdates {
+		if len(args) > 0 {
+			return fmt.Errorf("-u can only be used without arguments")
+		}
+	} else if len(args) < 1 {
 		return fmt.Errorf("no package names given")
 	}
 	device, err := oneDevice()
 	if err != nil {
 		return err
 	}
-	apps, err := findApps(args)
+	inst, err := device.Installed()
 	if err != nil {
 		return err
 	}
-	inst, err := device.Installed()
+
+	if *installUpdates {
+		apps, err := loadIndexes()
+		if err != nil {
+			return err
+		}
+		apps = filterAppsUpdates(apps, inst, device)
+		if len(apps) == 0 {
+			fmt.Fprintln(os.Stderr, "All apps up to date.")
+		}
+		return downloadAndDo(apps, device)
+	}
+
+	apps, err := findApps(args)
 	if err != nil {
 		return err
 	}
-	var toInstall []*fdroid.App
+	var toInstall []fdroid.App
 	for _, app := range apps {
 		p, e := inst[app.PackageName]
 		if !e {
@@ -58,7 +81,7 @@ func runInstall(args []string) error {
 	return downloadAndDo(toInstall, device)
 }
 
-func downloadAndDo(apps []*fdroid.App, device *adb.Device) error {
+func downloadAndDo(apps []fdroid.App, device *adb.Device) error {
 	type downloaded struct {
 		apk  *fdroid.Apk
 		path string
@@ -69,12 +92,19 @@ func downloadAndDo(apps []*fdroid.App, device *adb.Device) error {
 		if apk == nil {
 			return fmt.Errorf("no suitable APKs found for %s", app.PackageName)
 		}
+		if *installDryRun {
+			fmt.Printf("install %s:%d\n", app.PackageName, apk.VersCode)
+			continue
+		}
 		path, err := downloadApk(apk)
 		if err != nil {
 			return err
 		}
 		toInstall[i] = downloaded{apk: apk, path: path}
 	}
+	if *installDryRun {
+		return nil
+	}
 	for _, t := range toInstall {
 		if err := installApk(device, t.apk, t.path); err != nil {
 			return err

show.go

@@ -33,7 +33,7 @@ func runShow(args []string) error {
 		if i > 0 {
 			fmt.Printf("\n--\n\n")
 		}
-		printAppDetailed(*app)
+		printAppDetailed(app)
 	}
 	return nil
 }
@@ -47,13 +47,13 @@ func appsMap(apps []fdroid.App) map[string]*fdroid.App {
 	return m
 }
 
-func findApps(ids []string) ([]*fdroid.App, error) {
+func findApps(ids []string) ([]fdroid.App, error) {
 	apps, err := loadIndexes()
 	if err != nil {
 		return nil, err
 	}
 	byId := appsMap(apps)
-	result := make([]*fdroid.App, len(ids))
+	result := make([]fdroid.App, len(ids))
 	for i, id := range ids {
 		var vcode = -1
 		j := strings.Index(id, ":")
@@ -83,7 +83,7 @@ func findApps(ids []string) ([]*fdroid.App, error) {
 				return nil, fmt.Errorf("could not find version %d for app with ID '%s'", vcode, id)
 			}
 		}
-		result[i] = app
+		result[i] = *app
 	}
 	return result, nil
 }

testdata/scripts/cmds.txt

@@ -21,3 +21,6 @@ stderr '^usage: fdroidcl search .*regexp'
 stderr '-i.*Filter installed apps'
 
 ! fdroidcl
+
+! fdroidcl install -u some.app
+stderr 'without arguments'

testdata/scripts/device.txt

@@ -35,6 +35,8 @@ fdroidcl search -i -q
 stdout 'org\.vi_server\.red_screen'
 fdroidcl search -u -q
 stdout 'org\.vi_server\.red_screen'
+fdroidcl install -u -n
+stdout 'install org\.vi_server\.red_screen:2'
 
 # upgrade app to version code 2
 fdroidcl install org.vi_server.red_screen
@@ -45,6 +47,8 @@ stdout 'Installing'
 # app does not show up as upgradable
 fdroidcl search -u -q
 ! stdout 'org\.vi_server\.red_screen'
+fdroidcl install -u -n
+! stdout 'install org\.vi_server\.red_screen:2'
 
 # nothing to install or upgrade
 fdroidcl install org.vi_server.red_screen