vpm: add list command (#5888)

cmd/tools/vpm.v

@@ -9,7 +9,7 @@ import v.vmod
 
 const (
 	default_vpm_server_urls    = ['https://vpm.best', 'https://vpm.vlang.io']
-	valid_vpm_commands         = ['help', 'search', 'install', 'update', 'outdated', 'remove']
+	valid_vpm_commands         = ['help', 'search', 'install', 'update', 'outdated', 'list', 'remove']
 	excluded_dirs              = ['cache', 'vlib']
 	supported_vcs_systems      = ['git', 'hg']
 	supported_vcs_folders      = ['.git', '.hg']
@@ -79,6 +79,9 @@ fn main() {
 		'outdated' {
 			vpm_outdated()
 		}
+		'list' {
+			vpm_list()
+		}
 		'remove' {
 			vpm_remove(module_names)
 		}
@@ -283,6 +286,17 @@ fn vpm_outdated() {
 	}
 }
 
+fn vpm_list() {
+	module_names := get_installed_modules()
+	if module_names.len == 0 {
+		println('You have no modules installed.')
+		exit(0)
+	}
+	for mod in module_names {
+		println(mod)
+	}
+}
+
 fn vpm_remove(module_names []string) {
 	if settings.is_help {
 		vhelp.show_topic('remove')

cmd/v/help/default.txt

@@ -31,7 +31,8 @@ V supports the following commands:
    remove            Remove a module that was installed from VPM.
    search            Search for a module from VPM.
    update            Update an installed module from VPM.
-   outdated          List installed modules that need updates.
+   list              List all installed modules.
+   outdated          Show installed modules that need updates.
 * Others:
    build             Build a V code in the provided path (the default, so you can skip the word `build`).
    translate         Translate C code to V (coming soon in 0.3).

cmd/v/v.v

@@ -70,7 +70,7 @@ fn main() {
 			println('Translating C to V will be available in V 0.3')
 			return
 		}
-		'search', 'install', 'update', 'outdated', 'remove' {
+		'search', 'install', 'update', 'outdated', 'list', 'remove' {
 			util.launch_tool(prefs.is_verbose, 'vpm', os.args[1..])
 			return
 		}