os: remove base_dir(); dir() and base() fixes

vlib/os/os.v

@@ -642,21 +642,46 @@ pub fn file_ext(path string) string {
 	return path[pos..]
 }
 
-// dir will return the part of `path` before the last occurence of a `path_separator`.
+// dir returns all but the last element of path, typically the path's directory.
+// After dropping the final element, trailing slashes are removed.
+// If the path is empty, dir returns ".". If the path consists entirely of separators,
+// dir returns a single separator.
+// The returned path does not end in a separator unless it is the root directory.
 pub fn dir(path string) string {
-	pos := path.last_index(path_separator) or {
+	if path == '' {
 		return '.'
 	}
+	mut pos := path.last_index(path_separator) or {
+		return '.'
+	}
+	if path.ends_with(path_separator) {
+		pos--
+	}
 	return path[..pos]
 }
 
-// base_dir will return the base directory of `path`.
-pub fn base_dir(path string) string {
-	posx := path.last_index(path_separator) or {
+// base returns the last element of path.
+// Trailing path separators are removed before extracting the last element.
+// If the path is empty, base returns ".". If the path consists entirely of separators, base returns a
+// single separator.
+pub fn base(path string) string {
+	if path == '' {
+		return '.'
+	}
+	if path == path_separator {
+		return path_separator
+	}
+	if path.ends_with(path_separator) {
+		path2 := path[..path.len-1]
+		pos := path2.last_index(path_separator) or {
+			return path2.clone()
+		}
+		return path2[pos+1..]
+	}
+	pos := path.last_index(path_separator) or {
 		return path.clone()
 	}
-	// NB: *without* terminating /
-	return path[..posx]
+	return path[pos+1..]
 }
 
 // file_name will return all characters found after the last occurence of `path_separator`.

vlib/os/os_test.v

@@ -446,13 +446,15 @@ fn test_dir() {
 	assert os.dir('os') == '.'
 }
 
-fn test_basedir() {
+fn test_base() {
 	$if windows {
-		assert os.base_dir('v\\vlib\\os') == 'v\\vlib'
+		assert os.base('v\\vlib\\os') == 'os'
+		assert os.base('v\\vlib\\os\\') == 'os'
 	} $else {
-		assert os.base_dir('v/vlib/os') == 'v/vlib'
+		assert os.base('v/vlib/os') == 'os'
+		assert os.base('v/vlib/os/') == 'os'
 	}
-	assert os.base_dir('filename') == 'filename'
+	assert os.base('filename') == 'filename'
 }
 
 fn test_uname() {

vlib/v/builder/compile.v

@@ -27,7 +27,7 @@ fn get_vtmp_filename(base_file_name, postfix string) string {
 }
 
 pub fn compile(command string, pref &pref.Preferences) {
-	odir := os.base_dir(pref.out_name)
+	odir := os.dir(pref.out_name)
 	// When pref.out_name is just the name of an executable, i.e. `./v -o executable main.v`
 	// without a folder component, just use the current folder instead:
 	mut output_folder := odir
@@ -55,9 +55,7 @@ pub fn compile(command string, pref &pref.Preferences) {
 		println('compilation took: ${util.bold(sw.elapsed().milliseconds().str())} ms')
 	}
 	// running does not require the parsers anymore
-	unsafe {
-		b.myfree()
-	}
+	unsafe {b.myfree()}
 	if pref.is_test || pref.is_run {
 		b.run_compiled_executable_and_exit()
 	}
@@ -68,9 +66,7 @@ pub fn compile(command string, pref &pref.Preferences) {
 fn (mut b Builder) myfree() {
 	// for file in b.parsed_files {
 	// }
-	unsafe {
-		b.parsed_files.free()
-	}
+	unsafe {b.parsed_files.free()}
 }
 
 fn (mut b Builder) run_compiled_executable_and_exit() {
@@ -142,7 +138,7 @@ fn (mut v Builder) set_module_lookup_paths() {
 	// 3.2) search in ~/.vmodules/ (i.e. modules installed with vpm)
 	v.module_search_paths = []
 	if v.pref.is_test {
-		v.module_search_paths << os.base_dir(v.compiled_dir) // pdir of _test.v
+		v.module_search_paths << os.dir(v.compiled_dir) // pdir of _test.v
 	}
 	v.module_search_paths << v.compiled_dir
 	x := os.join_path(v.compiled_dir, 'modules')
@@ -263,7 +259,7 @@ pub fn (v &Builder) get_user_files() []string {
 			v.log('> That brings in all other ordinary .v files in the same module too .')
 		}
 		user_files << single_test_v_file
-		dir = os.base_dir(single_test_v_file)
+		dir = os.dir(single_test_v_file)
 	}
 	does_exist := os.exists(dir)
 	if !does_exist {

vlib/v/vmod/vmod.v

@@ -109,7 +109,7 @@ fn (mut mcache ModFileCacher) traverse(mfolder string) ([]string, ModFileAndFold
 		if mcache.check_for_stop(cfolder, files) {
 			break
 		}
-		cfolder = os.base_dir(cfolder)
+		cfolder = os.dir(cfolder)
 		folders_so_far << cfolder
 		levels++
 	}