vpm: warn when a module name is normalized into a different import path

Author: xRookieFight

cmd/tools/vpm/common.v

@@ -230,6 +230,16 @@ fn normalize_mod_path(path string) string {
 	return path.replace('-', '_').to_lower()
 }
 
+// Derive the import path of an installed module from its location relative to
+// `vmodules`. E.g. `<vmodules>/spytheman/vtray` -> `spytheman.vtray`.
+// Normalize both sides via `real_path` so macOS's `/tmp` -> `/private/tmp`
+// resolution doesn't leave the prefix unstripped.
+fn import_path_of(install_path string) string {
+	vmodules_real := os.real_path(settings.vmodules_path)
+	rel_install_path := install_path.trim_string_left(vmodules_real).trim_left(os.path_separator)
+	return rel_install_path.replace(os.path_separator, '.')
+}
+
 fn get_all_modules_for_search() []string {
 	working_server_url := get_working_server_url()
 	verbose_println_more(@FILE_LINE, @FN, 'working_server_url: ${working_server_url}')

cmd/tools/vpm/install.v

@@ -94,12 +94,26 @@ fn install_modules(modules []Module, selected_server_url string) {
 			}
 		}
 		println('Installed `${m.name}` in ${m.install_path_fmted} .')
+		m.warn_on_normalized_name()
 	}
 	if errors > 0 {
 		exit(1)
 	}
 }
 
+// Module names may contain characters that are not valid in V import paths, e.g. `-`.
+// Those are normalized away when the module is placed into `vmodules`, so point out
+// the resulting import path instead of leaving the mismatch for the compiler to report.
+fn (m Module) warn_on_normalized_name() {
+	import_path := import_path_of(m.install_path)
+	if import_path == m.name {
+		return
+	}
+	vpm_warn('`${m.name}` is not a valid V import path, it was installed as `${import_path}`.',
+		details: 'Use `import ${import_path}` to import it.\nConsider renaming the `name` field in the `v.mod` of the module.'
+	)
+}
+
 fn (m Module) install() InstallResult {
 	defer {
 		os.rmdir_all(m.tmp_path) or {}

cmd/tools/vpm/install_local_test.v

@@ -114,6 +114,33 @@ fn test_update_and_remove_with_capitalized_ident() {
 	assert !os.exists(publisher_dir)
 }
 
+// A module named e.g. `my-mod` is installed as `my_mod`, since `-` is not valid
+// in a V import path. Make sure the mismatch is reported with the resulting
+// import path, instead of leaving users to guess it.
+fn test_install_warns_about_normalized_module_name() {
+	vmodules_path := os.join_path(test_path, 'vmodules_normalized_name')
+	test_utils.set_test_env(vmodules_path)
+	repo_path := os.join_path(test_path, 'hyphenated_repo')
+	create_local_git_module(repo_path, 'my-mod')
+
+	res := cmd_ok(@LOCATION, '${vexe} install ${os.quoted_path(repo_path)}')
+	assert res.output.contains('`my-mod` is not a valid V import path, it was installed as `my_mod`.'), res.output
+	assert res.output.contains('Use `import my_mod` to import it.'), res.output
+	assert os.exists(os.join_path(vmodules_path, 'my_mod', 'v.mod'))
+}
+
+// Counterpart of the test above: a module name that is already a valid import
+// path must not trigger the warning.
+fn test_install_does_not_warn_about_valid_module_name() {
+	vmodules_path := os.join_path(test_path, 'vmodules_valid_name')
+	test_utils.set_test_env(vmodules_path)
+	repo_path := os.join_path(test_path, 'valid_name_repo')
+	create_local_git_module(repo_path, 'my_mod')
+
+	res := cmd_ok(@LOCATION, '${vexe} install ${os.quoted_path(repo_path)}')
+	assert !res.output.contains('is not a valid V import path'), res.output
+}
+
 fn create_local_git_module(repo_path string, module_name string) {
 	os.mkdir_all(repo_path) or { panic(err) }
 	os.write_file(os.join_path(repo_path, 'v.mod'),

cmd/tools/vpm/update.v

@@ -44,11 +44,7 @@ fn update_module(mut pp pool.PoolProcessor, idx int, _wid int) &UpdateResult {
 	// Derive the canonical module name from the install path so URL-based
 	// updates report the registered name (e.g. `spytheman.vtray` for
 	// `<vmodules>/spytheman/vtray`) instead of the bare URL-derived `vtray`.
-	// Normalize both sides via real_path so macOS's `/tmp` -> `/private/tmp`
-	// resolution doesn't leave the prefix unstripped.
-	vmodules_real := os.real_path(settings.vmodules_path)
-	rel_install_path := install_path.trim_string_left(vmodules_real).trim_left(os.path_separator)
-	name := rel_install_path.replace(os.path_separator, '.')
+	name := import_path_of(install_path)
 	vcs := vcs_used_in_dir(install_path) or {
 		vpm_error('failed to find version control system for `${name}`.', verbose: true)
 		return &UpdateResult{}