From 1f7b6e6a31afaaa00a57cf875b7a3a41af267250 Mon Sep 17 00:00:00 2001
From: Arthur Ozga <aozgaa-ms@outlook.com>
Date: Tue, 27 Sep 2016 10:54:03 -0700
Subject: [PATCH] More comments

---
 src/compiler/core.ts        | 11 +++++++++--
 src/services/completions.ts | 14 +++++++++++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index aca9701eee7..0b6dd3c9d7c 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -1015,7 +1015,9 @@ namespace ts {
         return path.replace(/\\/g, "/");
     }
 
-    // Returns length of path root (i.e. length of "/", "x:/", "//server/share/, file:///user/files")
+    /**
+     * Returns length of path root (i.e. length of "/", "x:/", "//server/share/, file:///user/files")
+    */
     export function getRootLength(path: string): number {
         if (path.charCodeAt(0) === CharacterCodes.slash) {
             if (path.charCodeAt(1) !== CharacterCodes.slash) return 1;
@@ -1074,7 +1076,7 @@ namespace ts {
 
     export function normalizePath(path: string): string {
         path = normalizeSlashes(path);
-        const rootLength = getRootLength(path);
+        const rootLength = getRootLength(path); // TODO: this expects un-slash-normalized strings. eg: 'x:\\...'
         const root = path.substr(0, rootLength);
         const normalized = getNormalizedParts(path, rootLength);
         if (normalized.length) {
@@ -1091,6 +1093,11 @@ namespace ts {
         return path.charCodeAt(path.length - 1) === directorySeparatorCharCode;
     }
 
+    /**
+     * Returns the path except for its basename. Eg:
+     * 
+     * /path/to/file.ext -> /path/to
+     */
     export function getDirectoryPath(path: Path): Path;
     export function getDirectoryPath(path: string): string;
     export function getDirectoryPath(path: string): any {
diff --git a/src/services/completions.ts b/src/services/completions.ts
index 00a5f80379b..04b68544376 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -322,10 +322,22 @@ namespace ts.Completions {
             return result;
         }
 
+        /**
+         * Given a path ending at a directory, gets the completions for the path.
+         */
         function getCompletionEntriesForDirectoryFragment(fragment: string, scriptPath: string, extensions: string[], includeExtensions: boolean, span: TextSpan, exclude?: string, result: CompletionEntry[] = []): CompletionEntry[] {
+            /*Debug.assert(fragment !== undefined);
+
+            if (fragment === "") {
+                fragment = ".";
+            } else {
+                fragment = getDirectoryPath(fragment);
+            }
+            */
+
             fragment = getDirectoryPath(fragment); // TODO: modify fragment so it respects our internal path representation?
             if (!fragment) {
-                fragment = "." + directorySeparator;
+                fragment = ".";
             }
             else {
                 fragment = ensureTrailingDirectorySeparator(fragment); // TODO: why is this necessary?