ignore files when compressing path components (#8)

* don't insert files into filename prefix trie

prefixes are properly considered unique over the set of directories/symlinks to
directories, not over the set of directories, files, and symlinks. in other
words, given a folder containing the directory "colibc", the directory
"clanker", and the file "clacker", "cl" would be a unique prefix indicating the
directory "clanker"

* bump version to 0.5.2

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "clanker"
-version = "0.5.1"
+version = "0.5.2"
 authors = ["Gregory Meyer <[email protected]>"]
 edition = "2018"
 description = "Minimalistic command prompt for fish."

src/compress.rs

@@ -25,6 +25,7 @@ use std::{
     borrow::Borrow,
     cmp, env,
     ffi::{CStr, OsStr, OsString},
+    fs::{self, Metadata},
     io::{self, ErrorKind},
     os::unix::ffi::OsStrExt,
     path::{Path, PathBuf},
@@ -103,7 +104,13 @@ fn compress(path: &Path) -> io::Result<String> {
                     continue;
                 }
 
-                filenames.push(filename.into_string_lossy());
+                if fs::metadata(&entry.path())
+                    .as_ref()
+                    .map(Metadata::is_dir)
+                    .unwrap_or(true)
+                {
+                    filenames.push(filename.into_string_lossy());
+                }
             }
 
             let trie: GraphemeClusterTrie = filenames.iter().map(|s| s.as_str()).collect();