DataLoaders 0: utility for hierarchical EntityPath from file path (…

…#4516)

A trivial PR that I extracted into its own in case this ends up being
controversial.

---

Part of a series of PRs to make it possible to load _any_ file from the
local filesystem, by any means, on web and native:
- #4516
- #4517 
- #4518 
- #4519 
- #4520 
- #4521

crates/re_log_types/Cargo.toml

@@ -50,6 +50,7 @@ arrow2 = { workspace = true, features = [
 ] }
 backtrace.workspace = true
 bytemuck.workspace = true
+clean-path.workspace = true
 document-features.workspace = true
 fixed = { workspace = true, default-features = false, features = ["serde"] }
 # `fixed` depends on `half`, so even though `half` is not directly used in this crate,

crates/re_log_types/src/path/entity_path.rs

@@ -118,11 +118,24 @@ impl EntityPath {
     ///
     /// The file path separators will NOT become splits in the new path.
     /// The returned path will only have one part.
-    #[cfg(not(target_arch = "wasm32"))]
     pub fn from_file_path_as_single_string(file_path: &std::path::Path) -> Self {
         Self::from_single_string(file_path.to_string_lossy().to_string())
     }
 
+    /// Treat the file path as an entity path hierarchy.
+    ///
+    /// The file path separators will become splits in the new path.
+    pub fn from_file_path(file_path: &std::path::Path) -> Self {
+        use clean_path::Clean as _;
+        Self::new(
+            file_path
+                .clean()
+                .iter()
+                .map(|p| EntityPathPart::from(p.to_string_lossy().to_string()))
+                .collect(),
+        )
+    }
+
     /// Treat the string as one opaque string, NOT splitting on any slashes.
     ///
     /// The given string is expected to be unescaped, i.e. any `\` is treated as a normal character.